MATHEMATICIANS AT WAR
Archimedes NEW STUDIES IN THE HISTORY OF SCIENCE AND TECHNOLOGY VOLUME 22
EDITOR Jed Z. Buchwald, Dreyfuss Professor of History, California Institute of Technology, Pasadena, CA, USA.
ASSOCIATE EDITORS Jeremy Gray, The Faculty of Mathematics and Computing, The Open University, Buckinghamshire, UK. Sharon Kingsland, Department of History of Science and Technology, Johns Hopkins University, Baltimore, MD, USA.
ADVISORY BOARD Henk Bos, University of Utrecht Mordechai Feingold, California Institute of Technology Allan D. Franklin, University of Colorado at Boulder Kostas Gavroglu, National Technical University of Athens Anthony Grafton, Princeton University Trevor Levere, University of Toronto Jesper Lützen, Copenhagen University William Newman, Indian University, Bloomington Lawrence Principe, The Johns Hopkins University Jürgen Renn, Max-Planck-Institut für Wissenschaftsgeschichte Alex Roland, Duke University Alan Shapiro, University of Minnesota Nancy Siraisi, Hunter College of the City University of New York Noel Swerdlow, University of Chicago Archimedes has three fundamental goals; to further the integration of the histories of science and technology with one another: to investigate the technical, social and practical histories of specific developments in science and technology; and finally, where possible and desirable, to bring the histories of science and technology into closer contact with the philosophy of science. To these ends, each volume will have its own theme and title and will be planned by one or more members of the Advisory Board in consultation with the editor. Although the volumes have specific themes, the series itself will not be limited to one or even to a few particular areas. Its subjects include any of the sciences, ranging from biology through physics, all aspects of technology, broadly construed, as well as historically-engaged philosophy of science or technology. Taken as a whole, Archimedes will be of interest to historians, philosophers, and scientists, as well as to those in business and industry who seek to understand how science and industry have come to be so strongly linked.
For other titles published in this series, go to www.springer.com/series/5644
Mathematicians at war
Volterra and his french colleagues in World War I
LAURENT MAZLIAK and ROSSANA TAZZIOLI
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Laurent MAZLIAK Histoire des Sciences Math´ematiques-IMJ & Laboratoire de Probabilit´es et Mod`eles Al´eatoires Universit´e Paris 6 4, Place Jussieu 75252 Paris Cedex 05 France
[email protected]
Rossana Tazzioli Laboratoire Paul Painlev´e Universit´e Lille 1 Cit´e Scientifique 59655 Villeneuve d’Ascq Cedex France
[email protected]
ISSN 1385-0180 ISBN 978-90-481-2739-9 e-ISBN 978-90-481-2740-5 Springer Dordrecht Heidelberg London New York Library of Congress Control Number: 2009927019 c Springer Science+Business Media B.V. 2009 No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Cover design: Boekhorst Design BV Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com)
Preface
Some scientists who attain eminence by the quality of their work also take leading positions in the scientific community and especially its institutions; and a few of those go on to act in the political sphere of their country. France is the nation in which this process has been most marked, or least infrequent. After the revolution of 1789 Lazare Carnot, Monge and Laplace held ministerial posts (and Lagrange was a senator), to be emulated later by Arago and Dupin. During the Great War Painlev´e was Minister of War and even Prime Minister for a short time. The edition of letters presented here belongs to that period, but the three French mathematicians involved are Painlev´e’s colleagues Emile Picard (1856–1941) (a permanent secretary of the Paris Acad´emie des Sciences from 1917 until his death), Emile Borel (1871–1956) (to be a minister in the 1920s) and Jacques Hadamard (1865– 1963). The link between them is provided by their Italian colleague Vito Volterra (1860–1940), a Senator since 1905; for, unlike the French trio (with Borel as partial exception: his archive exists at the Acad´emie), Volterra always carefully maintained his papers, so that after his death he left a huge Nachlass. After lengthy discussions among his own children, in the late 1970s the collection was handed over to the Accademia Nazionale dei Lincei in Rome; he had been a member and indeed President, and a son was then a member. I spent a week working on this collection in 1982, when the cataloguing was nearing completion; one of the cataloguers was a lady who had been Volterra’s secretary in his final years. The section of correspondence includes 410 items for Borel, 82 for Hadamard and 204 for Picard; the selection below comprises 115 items from those collections, giving a complete coverage of the period 1914–1920. The tone of the exchanges seems warmest with Borel, who is the closest in spirit and energy to Volterra. However, other affinities appeared during the War, such as with Hadamard, who shared with Volterra a Jewish origin. All four men had built up their considerable reputations largely through their contributions to real- and complex-variable analysis, not only in established areas such as differential equations and function theory but also in the recent adaptation and application of set theory to produce subjects such as functional analysis and integral equations. However, this mathematics does not feature strongly in the letters below. The scientific topics noted in the letters are concerned with applications of mathematics such as the means of detecting enemy batteries, and also submarines, v
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by aural or sonic means, and the functioning of airships. Volterra and Borel acted as important managers of the development of science during it. The letters are dominated by various social and personal issues. They include recent war news and its reportage, the place of Italy in the War (she declared for the Allies in May 1915), news of the families (including the deaths of sons in battle for Picard and Hadamard) and of colleague mathematicians, awards of honorary degrees, the establishment of committees concerning various initiatives and activities, and the restoration of normal academic relationships after the cessation of the War on 11 November 1918. Specific contacts include a lecture course on partial differential equations and the motion of waves that Hadamard delivered in Rome for Volterra in May 1916. The editors flesh out the details of the exchanges in an extensive introduction and in numerous footnotes to their transcriptions, and treat some related topics in a final part. Thereby a small but valuable part of the Volterra mine is brought to the surface. 11 November 2008
Ivor Grattan-Guinness
Acknowledgements
We are pleased to thank all the persons who have helped us to complete the present work by reading the manuscript and allowing us to correct numerous mistakes, and by providing additional information. In particular, we warmly thank Tom Archibald, Annalisa Capristo, George Cardosi, Jens Høyrup and Pietro Nastasi, for the time they generously offered to us. We have been honored that Ivor Grattan-Guiness has accepted to write a preface for the book. We would like also to thank our colleagues from the Equipe d’Histoire des Math´ematiques from the Institute of Mathematics of University Pierre et Marie Curie, Paris, France. We had numerous exchanges with them on the topic of the book. Moreover, this book is part of a vast international research project about mathematics and mathematicians around World War 1, a project in which the Equipe d’Histoire des Math´ematiques of Paris 6 has been deeply involved for several years. Almost all the archival material of this book comes from Volterra’s personal archive, kept at the Accademia dei Lincei, Roma. We express our gratitude to our colleague Giorgio Letta from Pisa for his constant support and providing us advices and useful contacts in the staff of the Academy. It is our pleasure to thank the Cancelliere of the Academy, Dr. Ada Baccari, the director of the archive service, Dr. Marco Guardo, Dr. Enrica Schettini and all the personnel of the service, for having offered us exceptional conditions to rummage through Volterra’s correspondence and accepted the present publication. We found also interesting additional material in other institutions such as the Paris Academy of Science, the military archive service of the French army (SHAT), the French national archives in Paris (CARAN). All the personal of these institutions are warmly thanked for their kindness. Parts of this book have been completed when the second author benefited of a research allocation by the Fondation des Sciences Math´ematiques in University Paris 6. And we both have enjoyed an invitation to a research-in-pair stay of several days at the CIRM in Marseille, France. We express our gratitude to the staff of these institutions as well. January 2009, Paris-Lille, France
Laurent Mazliak Rossana Tazzioli
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Contents
Part I Introduction to the Letters ♦1
What Is this Book About? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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♦2
The Protagonists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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♦3
Italy and France at the Eve of WW1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
♦4
Vito Volterra and His Institutional Activity . . . . . . . . . . . . . . . . . . . . . . 17
♦5
Volterra and Italian Interventionism Between 1914 and 1915 . . . . . . 21
Part II Volterra’s Exchanges with Borel, Hadamard and Picard in World War One Volterra’s Exchanges with Borel, Hadamard and Picard in World War One . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Part III Appendices ♥7
The Case of P´er`es . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
♥8
Persuading the American Jewish Community . . . . . . . . . . . . . . . . . . . . 165
♥9
French Propaganda . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
♥ 10
Cultural Relations Between Italy and France . . . . . . . . . . . . . . . . . . . . 181
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 ix
Chapter ♦ 1
What Is this Book About?
Between 28 and 30 September 1973, an important conference was held at the university of Grenoble (France) under the title France and Italy during World War 1. The proceedings of the conference were subsequently published by Grenoble University Press in [25]. The conference gathered important contributions about many aspects of the Franco-Italian relationship in the troubled years of the world war. Apart from the military and diplomatic questions directly related to the war, the book deals also with the cultural, economic and social sides of the conflict. One may in particular find a good deal of information about the main actors who played a part in the relations between the two countries in these years, on both the Italian and the French sides. One may also obtain a very complete picture of how each country saw the other one during all the phases of the war from its beginning in France in August 1914 until its bitter conclusion for Italy in 1919 at the peace conference, by way of the Italian decision for intervention and the complicated diplomatic meanderings of the Italian war aims. The Part I of [25], entitled “Public Opinion”, gives a remarkably precise description of the changes in the attitudes of both populations towards each other. It is however remarkable that scientific relations are hardly considered in this collection of articles. This may seem strange at first glance as the roles of scientific experiments and technological research were of prime importance during World War 1. The historiography of the war has relatively recently focused on the question of the scientific and technological contacts between the belligerents. We note a remarkable book (in French), entirely devoted to this question, produced by the P´eronne Historial [3], where however the Italian case is not considered. In recent years, several large scale research programs have initiated a wide study of how mathematicians met the exceptional experience of the war and what were the consequences for the mathematical disciplines. An international meeting on the subject was held in Marseilles in 2007 at the CIRM where a large number of specialists presented new considerations on the topic. This conference became itself the source of further works. We mention in particular two books which are being prepared at the moment. One is devoted to local studies of the situation of mathematics in several places in the world in the period of WW1. A second one, devoted to the
L. Mazliak, R. Tazzioli, Mathematicians at war, Archimedes 22, C Springer Science+Business Media B.V. 2009 DOI 10.1007/978-90-481-2740-5 1,
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What is this Book About
French situation, chooses an angle of attack through the personal war experience of several French mathematicians from different locations, belonging to different generations and showing different mathematical interests. The present book can also be considered as a consequence of the Marseilles 2007 conference. During the meeting, we (Rossana Tazzioli and Laurent Mazliak) noticed how both of us had used the great richness of the mathematician Vito Volterra’s correspondence for our studies on WW1, and this encouraged us to prepare an edition of the war correspondence between Volterra and his French colleagues during the First World War. This is precisely the content of the present book. August 1914 is easily selected as a natural beginning of the period in which we examine the letters as it marks an immediate change in the tone and the contents of the letters. On the other hand, it is a more difficult task to decide when to stop the study, because some aspects of the war are present in the letters long after 1918. Therefore, our choice is obviously debatable. Volterra’s personal archives in the Accademia dei Lincei in Rome contain an enormous correspondence with many scientists of his time, famous or unknown, as well as with politicians and administrators due to the political rˆole Volterra played during his life. Even limited to the period of WW1 and to the French correspondents, one must face an impressive number of letters. Most of them were, however, written by only 3 correspondents, on whom we focus our study. These correspondents are Emile Borel (1871–1956), Jacques Hadamard (1865–1963) and Emile Picard (1855–1941) who are among the most influential mathematicians of their generation. For all of them, the correspondence with Volterra began long before WW1 (at the end of 19th century), and went on long after – in fact until Volterra’s death in 1940. All three men had both a professional and a personal relationship with Volterra, though their characters, their mathematical and social interests, and the way they faced the development of the science of their time implied noticeable differences in these three relationships. Borel was certainly the closest to Volterra. The major part of the correspondence is between these two. Borel’s own interest in politics and social life played a part in the construction of the friendship with Volterra. In her memoirs [39], Borel’s wife Marguerite Appell, who was the novelist who wrote under the nom de plume Camille Marbo, gives many hints of this intellectual proximity between her husband and Volterra. The relation with Picard, though very cordial and confident, seems to have been more formal. Picard and Volterra, two first rate mathematicians of the end of the 19th century, whose stellar career had begun when they were extremely young, felt high esteem for each other. During the 1910s, both occupied important official academic positions, both were Academicians in their country (Volterra at the Lincei, Picard at Paris Academy of Science) and both were convinced of the importance of the Academy. The letters with Picard, even when they are written in a more private tone, show more self restraint than those with Borel or Hadamard. It is with the latter that Volterra was scientifically the closest. Since the first years of the century, Hadamard had used Volterra’s studies on functions of line (functions defined on a space of functions) and functional calculus in order to develop new methods for Partial Differential Equations and Potential Theory. Apart from a short journey to Switzerland in 1917,
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Hadamard’s only mathematical stay abroad during WW1 was a journey to Rome; the organization of this journey is the main subject of the letters between Volterra and Hadamard at this time. What is possible to learn from this correspondence? We may emphasize three main points: (i) Information about the immediate context; (ii) Information about how the rˆole of a scientist evolved in a completely new surrounding; (iii) Information about how these mathematicians considered the difficult relationship between their ideal of science and – so to speak – their ideal of war. Let us give some details on these three points. The set of letters between Volterra and his three French colleagues obviously offers a vivid picture of their activity during the period of the war. We see how the war enters their existence and how each protagonist describes the social situation in his country, and gives his opinion about military affairs and their evolution. This aspect also allows us to compare how Borel, Hadamard and Picard faced the crisis each with his own sensibility and limits. The letters moreover show how their main interests were transformed. Each of them began to care about entirely new subjects – mostly not mathematical at all – related to the war effort. During the four years of the war, this war effort changed in nature and in importance, and all the four dealt with various technical or organizational programs that can be traced in the letters. And obviously, the correspondence, which makes reference to numerous people mostly from the scientific community but also from many different spheres of the society, gives an important picture of the circles they frequented during the war. Reading the letters gives information about who was in contact with whom and which members of these circles gained influence or prestige during the war. We added comments in footnotes to give some information about all the people mentioned in the letters. The second kind of information we can glean from the letters is how the rˆole of a scientist – mainly of a mathematician – during the war was questioned by the protagonists and what kind of answer they tried to propose. An immediate observation is that the four mathematicians are forced to expose parts of their personal life and feelings. In the letters, one can find details about daily life. And much more dramatically, one finds the testimonies of the casualties due to the war. As a sad coincidence, Borel, Picard and Hadamard had all lost at least one child during the war, and they had to communicate the news to Volterra, in heart-breaking terms that give a suddenly different tone to the letters. In addition to these private trials, they had to face the destruction of much of what had been, before the war, the center of their lives. The most spectacular and dramatic aspect of this destruction was, perhaps, the accumulation of casualties among the students of the Ecole Normale. As is well known, this was the cause of Borel’s resignation from his position of vice-director of the Ecole Normale after the war, because he could not bear the atmosphere of the school in mourning. All these aspects implied something quite new in this kind of correspondence: the intrusion of anxiety for the future. Along the same lines, it must be emphasized how the very nature of the correspondence immediately changed in August 1914: from one day to the next, mathematics has completely disappeared. On the other hand, the protagonists seem to come closer to politics. As we shall see, for Borel, it was even more than just coming closer.
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♦1
What is this Book About
Borel became a real politician during the war. What is immediately seen in the letters (except maybe Hadamard’s) is that the men wanted to enter the political game at the highest level. It is difficult to know to what extent they were really convinced of the importance of what they were doing in relation to the war. But they certainly wrote as if this importance was crucial. This aspect of playing a big game is particularly striking in Volterra’s letters, perhaps accentuated by the use of French language, which was not his mother-tongue though his knowledge of it was excellent. Volterra seemed to feel quite comfortable in the clothes of a politician, organizing ministerial exchanges or sending heated patriotic messages to his French colleagues. This seems, somehow, an overestimation of their own rˆole, and may have become a source of bitter delusion after the war when they all observed that, despite the personal sacrifices they had faced and what they had considered as an enormous engagement in the war effort, the after-war world did not pay the tribute they may have expected. This appears in full light in Picard’s letters written rather shortly after the war, when the inflexible mathematician realized how he remained isolated in his anti-German ostracism. Many traces of bitterness can be found in the letters after the war. This is an important hint of the accelerated generational effect that deeply reshaped the French (and to a lesser extent the Italian) mathematical community after WW1. On that basis, the present correspondence offers an interesting complement to other studies such as the book [22]. A third point of interest is the understanding of how the four mathematicians had succeeded in building bridges between what they understood as being the ideal of science and how they considered the war. This point is less clear to us than the former ones, but it is certainly an important one. All the four mathematicians had been brought up with notions of a science of progress, bringing enlightenment to humanity. They were distinguished scientists and felt themselves responsible for the expansion of science. The question therefore becomes: How had such people managed to make this generous humanistic vision fit with the military effort and the violence of the war. Perhaps surprisingly, there is no trace of schizophrenia in their writings: they did not avoid the problem by considering that these were two non-overlapping domains. On the contrary, though it is seldom asserted in black and white, a vague notion of “war for justice” seems to mirror an (even more vague) notion of “just science”. In Volterra’s letters, this notion sometimes verges on amazing naivety. Volterra behaves like an armchair strategist giving his opinion on how the war should be conducted. He recurrently shows great confidence in the allies’ cause and uses the rather strange words The war is going very well in order to convince himself that he is on the side of justice. A question arises with particular acuteness from the documents we present to the reader: What is the exact connection between the history of mathematics and the history of mathematicians? As we have already mentioned, the letters show that Volterra and his French colleagues were mostly not doing mathematics during the war. But to what extent can it be said that they were identified, or acting, or reacting, as mathematicians? Let us formulate the question in another way. The aim of several studies, in particular the aforementioned book about the French situation [22], or the book [21], is to detect the effect of the war on mathematics. Here the problem would
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be in a way the converse one. Issues concerning whether or not mathematicians adopted a specific position towards the war arise from this collection of letters. Let us finish this introduction with a brief comment on the three parts into which the book is divided. The first one is dedicated to a description where we provide general information on the protagonists of the correspondence and on the situation of their countries. This should help the reader to acquire an overview of the background to the exchanges between Volterra and his French colleagues. Volterra being the central figure for the documents we present, we emphasize slightly more on the Italian picture of these years, which is often less commented on than the French one. The different sections of this first part are labeled with the symbol ♦ followed by a number. The second part of the book presents the letters exchanged between Volterra and Borel, Hadamard and Picard after 1914. The letters (in French) are transcribed in extenso and left in the original language. To facilitate their reading, we add numerous footnotes to clarify the context when it is necessary and to provide additional information on themes evoked in the letters. In particular, we give some details on each person mentioned in the documents; the reader will find an index of these names at the end of the book. Finally a third part is composed of several small chapters on particular themes hardly mentioned in the correspondence. As said above, the second part is strictly limited to the letters exchanged between the four mathematicians. Therefore, in order to improve the picture so far obtained, we exploit numerous documents from other sources. The choice of the subjects of the different chapters has been guided by the interest of these documents. We emphasize those subjects for which, as far as we know, little secondary literature is available, at least in the framework of the war period and the mathematical community. Each chapter includes an introduction to the theme and a selection of previously unpublished documents. We think that this part can offer interesting complementary information to the reader. The different sections of this third part are labeled with the symbol ♥ followed by a number, and the documents we present are labeled by a ♣ also followed by a number.
Chapter ♦ 2
The Protagonists
This book is obviously not the place to give a full portrait of Volterra and his French colleagues. They are too huge and complex scientific personalities for that. The collected works of each of them have been published in [8, 27, 47] and [57]. Information about their lives can be gathered from various sources, such as the numerous obituaries which have appeared after their deaths. Let us moreover mention that several biographies, of different kind and completeness, can be found on Borel, Hadamard and Volterra in recent literature. On Volterra, the interested reader can refer to the large study by Goodstein [23] (in English) which was successfully completed by Guerraggio and Paoloni’s book [24] (in Italian). About Hadamard, a book (in English) by Mazya and Shaposhnikova [43] appeared some years ago, which provides a detailed biography of the very long life of the French mathematician and presents many interesting original documents. As for Borel, the only biography available at the moment is a small book (in French) written by Guiraldenq [26], which offers a well documented picture of the man and reproduces several interesting rare documents. For the reader’s comfort, we nevertheless briefly sketch the biographies of our main protagonists. Vito Volterra was born in 1860 in Ancona, the only child of Abramo, a Jewish cloth merchant, and his wife, Angelica Almagi`a. Vito’s father died when he was two years old. Angelica and her son, in dire financial straits, had to move to the house of a relative, Alfonso Almagi`a, an employee of the Banca Nazionale. Later on, they all moved to Turin and then Florence, where Vito attended secondary school. He had an outstanding teacher, the physicist Antonio Roiti, who played an important role in Volterra’s education. Though Vito was greatly interested in scientific problems, his family urged him to follow a commercial career, or to become a bank clerk, because of their critical financial situation. Through Roiti Vito got an assistant position in the Physics Laboratory of the University of Florence and could then pursue his scientific studies. In 1878 Volterra entered the Faculty of Mathematics, Physics and Natural Sciences of the University of Florence and two years later passed his examination to the Scuola Normale Superiore of Pisa, where he attended the lectures of Enrico Betti and Ulisse Dini. In 1882, he graduated in physics with a thesis on hydrodynamics
L. Mazliak, R. Tazzioli, Mathematicians at war, Archimedes 22, C Springer Science+Business Media B.V. 2009 DOI 10.1007/978-90-481-2740-5 2,
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The Protagonists
supervised by Betti. The following year he won the competition for a professorship of rational mechanics at the University of Pisa. In 1892, he moved to the University of Turin and in 1900 succeeded Eugenio Beltrami as professor of mathematical physics at the University of Rome. The same year he married his cousin Virginia Almagi`a. Volterra’s wide scientific production concerns various subjects of mathematics and mathematical physics – terrestrial mechanics, rational mechanics, elasticity, hydrodynamics, electrodynamics, differential equations, integral equations (we mention the so-called integral equation of Volterra type) and their applications to biology and economical models. He also introduced the concept of function of line (later called functional by Hadamard), which opened a new and fruitful research field – known as functional analysis – a part of which was connecting the theory of integral and integro-differential equations. Volterra soon became an important public and political figure. In 1887 he was elected corresponding member of the Accademia Nazionale dei Lincei (in 1899 he became an ordinary member); in 1897 he founded the Italian Physics Society (SIF, Societ`a Italiana di Fisica); in 1905 he was nominated Senator of the Kingdom. We shall describe in ♦ 4 below his exceptional involvement in the creation of many scientific institutions – often on the models of French institutions – so that Italy could play a major role in world science (see in particular [45]). At the outbreak of World War I, Volterra enlisted in the engineers corps (Genio) although aged 55! In 1922, when Fascism came to power in Italy, Volterra immediately opposed it. In 1925, he signed the intellectuals’ manifesto against fascism – drawn up by Benedetto Croce – and in 1931 refused to take an oath of loyalty to Fascism. As a consequence of his refusal, he was expelled from the University of Rome and, in 1932, from all Italian cultural institutions. In 1940 he died isolated and with no official recognition. Emile Borel was born in 1871 in Saint-Affrique, department of Aveyron in the south-west of France, into a modest middle-class protestant family. He kept tight links with his birth town during his whole life. After brilliant secondary studies, he prepared for the competitive examination leading to the Grandes Ecoles, the higher education cradle of the French scientific elite. Together with him, in the famous teacher Niewenglowski’s class, was the mathematician Darboux’s son; Borel himself described how during an invited visit at Darboux’s home, he discovered his passion for scientific (and more specifically mathematical) research, and learned that the Ecole Normale Sup´erieure was the right place to begin a scientific career. Having entered the Ecole Normale, Borel immediately specialized in mathematics and began fundamental studies on divergent series for which he introduced different modes of summability. These studies soon brought him to fundamental considerations about set-measures (see [29] for details). In less than ten years, he presented, in a series of outstanding works, the basic concepts of measure theory which afterwards allowed Lebesgue to build his integral and to revolutionize analysis. Also in relation with measure theoretic considerations, beginning in 1905 he focused on probability theory. He became a major renovator of probability, tracing the path for
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the axiomatic formalization based on measure theory achieved by Kolmogorov in his Grundbegriffe des Warscheinlichkeitsrechnung [31]. Apart from his intensive research activity, Borel always worried about the mathematician’s social rˆole and he left many texts about vulgarization, philosophy and teaching of mathematics. Through the relations of his wife (daughter of the mathematician Paul Appell) who became a celebrated novelist under the pseudonym of Camille Marbo (for MARguerite BOrel), Borel became involved in political and social life. In 1905, they created together the journal La Revue du Mois which became for 10 years the major intellectual general publication in France with (moderate) leftist orientation. WW1 accelerated Borel’s direct political engagement; he was first elected mayor of his native town, and then deputy of Aveyron department in 1924. The following year, the new Prime Minister, Borel’s friend Paul Painlev´e nominated him minister of the navy, a position he held only for some months. Member since 1921 of the Paris Academy of Science, Borel always wished to employ his political influence to serve the development and the spread of mathematics. He played a fundamental part in the creation of the Institut Henri Poincar´e (IHP) in Paris in 1928 which became the principal French research center in mathematical physics and in probability. Borel in particular continuously acted during the 1930s to facilitate the invitation to the IHP of many mathematicians and physicists of the time, including Soviet scientists who encountered more and more obstacles to international travel. During the German Occupation of France, he was imprisoned for a short while in 1941 due to his political commitments (see [42]). Borel died in 1956 in Paris. Emile Picard was born in Paris in 1856. A decisive event occurred in 1870 when his father died during the siege of Paris by the Germans, leaving a widow and two sons in a difficult position. So, from the beginning of his life, Emile had therefore formed his opinion about German brutality. Later, he entered the Ecole Normale and received the agr´egation of mathematics degree in 1877 being ranked first. The following years he proved two fundamental results on entire functions and on the solution of differential equations by successive approximations, gaining him general applause and an astonishingly young nomination for the Academy of Science in 1881. Eventually, he was elected only in 1889. Between 1891 and 1896, Picard published his masterpiece, the Trait´e d’Analyse, the three volumes of which immediately became a classic. Picard was also interested in applying analysis to the study of elasticity, heat and electricity. He is considered as one of the main French specialists in mechanics of the beginning of 20th century. A very conservative man with strong rightist political views, Picard was deeply concerned with academic politics and obsessed by the glory of French science, confronted by the achievements in German science. WW1 was for him the occasion of an anti-German outburst of an incredible violence, fed by the personal tragedy that war brought to his life. This violent attitude is omnipresent in the letters we publish. After WW1, Picard was still a universally respected scientist, but felt himself more and more isolated in his wrath against anything related to Germany. As a cruel irony, the old man died in 1941 in occupied Paris.
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The Protagonists
Jacques Hadamard was born in 1865 in Versailles. Heir of the great tradition of the analysts of the 19th century, he became involved in the systematic study of the convergence of power series and analytical functions. He obtained an important result, the so called 3 circles theorem.1 From these studies, and especially from those on Riemann’s ζ function, he obtained important conclusions in the analytical theory of numbers. In 1896, he proved the celebrated theorem on the distribution of prime numbers, proved also independently the same year by de La Vall´ee-Poussin. Hadamard was always interested in problems originated from Physics. One of his main fields of interest at the beginning of 20th century was the study of Partial Differential Equations for which he introduced new methods. In particular, he realized how Volterra’s formalism of functions of line could be applied to potential theory and became one of the main promoters of functional calculus. Hadamard’s lectures at the Coll`ege de France on the topic strongly influenced many French mathematicians of the younger generation (Fr´echet, L´evy, Gateaux, P´er`es, . . . ). Gradually, Hadamard transformed these lectures in a seminar where recent papers were discussed by various, generally young, mathematicians. The S´eminaire Hadamard was an unavoidable passage point for the analysts in France in the inter-war period. As with Borel, political and social life always concerned Hadamard, though he never became a politician. After WW1, he became a convinced pacifist, and a supporter of the normalization of relations with the new Soviet Union (however he never became a communist). He was the guest of honour in 1934 of the French science week in USSR. The dramatic consequences of 1940 invasion of France forced the 75 years-old icon of French mathematics to emigrate in 1942 to the USA where influential people had invited him. Coming back to France in 1945, he lived another 20 years and died at the venerable age of 98.
1 The theorem asserts that the maximum of an analytical function on a disc is a log-convex function of the radius
Chapter ♦ 3
Italy and France at the Eve of WW1
In this introductory section, we wish to present a quick and parallel picture of the situation in both countries just before the war broke out. The aim of this short chapter is therefore to provide landmarks for the reader about the general background in which the correspondence to follow was written. Numerous texts have been published to describe the situation of Italy and France at the beginning of 20th century in all its aspects: political, economical, sociological, cultural and so on. For instance, we invite the reader to consult the following encyclopaedic books [4, 19, 20] to complete the scattered information we give in the present section. Let us begin by a description of the political systems in both countries. Since the collapse of the Second Empire which followed the French defeat in the FrancoPrussian war of 1870, France was a republic with a parliamentary regime, the so-called IIIrd Republic. The prime minister (Pr´esident du Conseil) and his Government were chosen by the parliament and this lead to frequent changes in the governments’ composition. They hardly lasted more than one year. The executive power was formally headed by a President of Republic, also elected by the Parliament, who had in fact little personal power; the position was often considered as the crowning and the end of a political career. In 1913, Raymond Poincar´e, a cousin of the mathematician Henri Poincar´e, had been chosen as President of the Republic. Contrary to France, a long standing unified country, the existence of modern Italy as a nation started in 1860. In that year, the various smaller states into which Italy had been politically and administratively divided were unified in a process called the Risorgimento. The government of Piemonte (the northwestern region of Italy with Turin as capital) obtained significant popular consent and became the leader of the idealistic patriotic and democratic mobilization against Austria. After popular uprisings, two wars of independence against Austria, and intense diplomatic activity, the Unification of Italy was finally achieved. Vittorio Emanuele II, already king of Piemonte, became king of Italy. Italian politics remained poisoned after the Unification by the intricate question of the pope’s status, the so-called Roman question. In 1870, after the defeat of the papal army, Rome became the capital of unified Italy and Pope Pius IX lost his temporal powers. Pius IX never accepted, at least officially, the Laws of Guarantees (1871) voted by the Italian parliament. These laws left the free use of the Vatican to
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the papacy, granted the right to send and receive ambassadors and offered a tribute of about three million liras each year, but denied sovereignty of the pope over this territory. Pius IX always considered himself and the Vatican as opponents of the Italian government. He proclaimed the dogma on infallibility of the pope (1870). As a consequence, the pope declared himself to be the sole and supreme legitimate power over all Catholics. Catholics were requested not to participate in Italian politics and this attitude continued for a long time. That provoked a deep separation between Italian state and Roman Catholic Church. Both Pius IX and Vittorio Emanuele II died in 1878. In 1891 pope Leo XIII published the encyclical Rerum novarum, which presented a third political line between capitalism and socialism – the Catholic line. The followers of this political line could be considered as a moderate catholic Centre. The king of Italy, Umberto I, did not openly oppose these ideas, and alliances between politicians and members of the Catholic Church developed.2 . As a result of the aforementioned difficult relations between the Church and the young state, in the times immediately following Unification, Italian intellectuals (among mathematicians, let us quote Enrico Betti, Francesco Brioschi, Felice Casorati, Luigi Cremona or Eugenio Beltrami) were anticlerical and defended the idea of separation between the Church and the state. They held many public and political offices and saw themselves as the builders of the new Italy. At the beginning of the 20th century, the relationship between the Catholic church and the French government was also in a state of crisis. The Dreyfus Affair had torn and profoundly marked French society in the 1890s, and its resolution fixed the great principles on which French politics has been officially based afterwards. At the eve of WW1, even if several groups, as the virulent, monarchist and anti-semitic Action Franc¸aise kept a real influence among upper classes, the republican regime was well established. The separation between the religious powers and the state was a matter of fact since 1905. The Roman Catholic Church, though it had still a great audience in the French population, had seen a continuous weakening of its presence in public life, especially among the ruling political class. After the end of the Dreyfus affair, the latter was mostly composed of people from the radical party. This party was a (very) moderate leftist group which, apart from promoting spectacular laws as the separation between church and state, mostly tried to put small doses of social progress into a middle-class conservative policy. Many politicians we shall encounter in this book participated in this trend. They cultivated an anticlericalism directed against the claims of the Catholic Church to play a major role in public life, and also an idea of progress to be attained by rationalism and science, as well as a strong conviction about the civilizing mission of Europe – and, obviously, above all of France. As many politicians of the aforementioned group came from
2 On the relations between Italy and Vatican see for example [49] on the Catholic Church during the First World War see [11]
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the academic world, one spoke about the Republic of Professors.3 A particularly well represented institution in this group was the Ecole Normale Sup´erieure, which, since the 1880s, had supplanted the Ecole Polytechnique as the main elitist academic center in France. Let us now have a look at the economic issues. While at the eve of the war France was one of the more developed countries of the world, Italy still tried to close the gap between the two. After Unification, Italy had tried to modernize agriculture and to develop industry, encountering many difficulties due to the economic and political differences between the north and the south of the country. The situation of the south was particularly difficult, giving rise to what was called “the Southern question” in Italian politics. The north was in a better position. In the last years of the 19th century, agricultural and industrial development had recovered vigorously, with constantly increasing rates of growth until 1908. Since the 1880s, an industrial bourgeoisie was the most influential part of the country and imposed its way of life in the main towns. The working class also issued from industrialization, mainly concentrated in the Milan-Turin-Genoa triangle. Concerning foreign politics, noticeable differences appeared between the two countries. France had finally overcome the panic that followed 1870 collapse. The defeat had implied the loss of vast eastern territories (the Alsace region and of a large part of the department of Moselle), and the fear of complete diplomatic isolation due to Bismarck’s politics. The strategic agreement with Great Britain and Russia (the so-called Triple Entente), signed in 1907, comforted the country which was subsequently confident about its safety. On the contrary, Italy was a member of the Triplice Alliance (together with Germany and Austro-Hungary) since 1882. The alliance was a military treaty which guaranteed mutual help in case of aggression. Italy signed the treaty – in spite of tense relations with Austria concerning the terre irredente (Trentino, Trieste and Fiume), which remained in Austrian possession after 1870 – for two essential reasons: (i) Italy feared French aggression; (ii) Italy needed to be under the protection of Austria and Germany in order to develop its colonial policy. Precisely as concerns the colonial situation, the French one was now almost stabilized. The rivalry between France and Great Britain – which had poisoned a large part of the 19th century – was now almost forgotten, France having accepted, like it or not, to play the second role behind the enormous British empire. Tension had however repeatedly occurred with Germany, in particular about the question of Morocco, which Great Britain accepted to include in the French sphere of influence. Germany however intended to increase its economic presence in that part of Africa, and in 1905 and above all in 1911, the situation turned ugly between France and Germany and a risk of war was evoked, but the calm came back. On its side, Italy, after the conclusion of the Triplice alliance, was ready to venture into colonial wars in East Africa. In 1882, it conquered the part of Eritrea
3 The expression is the title of a book (published in 1924) about the radical-socialist party by the French publicist Albert Thibaudet (1874–1936).
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which is on the Red-Sea shore, and in 1885 Italy began a war against Ethiopia, which after ten years resulted in the independence of the invaded country. Using the aforementioned 1911 diplomatic crisis between Germany and France, Prime Minister Giovanni Giolitti declares war on Libya and then on Turkey. In 1912, Italy took possession of the Dodecanese islands in the Aegean sea, and the Cirenaica and the Tripolitania in Libya. Many Catholics and nationalistic intellectuals, more and more numerous, supported the war. Let us for instance quote the writers Gabriele D’Annunzio, but also Corradini, Papini, and Prezzolini (see ♦ 5). In 1910 the Associazione Nazionale Italiana (National Italian Association) was founded, and the first nationalistic newspaper, a bimonthly journal called Il Regno, started its publications. In 1914, it became a daily newspaper. Let us finally mention that in the Franco-German rivalry, the destiny of the lost territories of Lorraine and Alsace remained an unsolved question. However, though the statue representing Strasbourg on the Place de la Concorde in Paris was still covered with a black veil, the loss was largely taken for granted by the French population. However, the 1870 defeat remained present in the memories and several characters we shall encounter in the correspondence kept personal cruel memories of this tragic event, either because their family experienced a voluntary exile in order not to become German citizens (as it was the case for the mathematician Paul Appell, Borel’s father-in-law), or because they suffered from the war (as was the case of Picard, which at least partly explains his violent anti-Germanic attitude during the war).
Chapter ♦ 4
Vito Volterra and His Institutional Activity
In 1914, when the First World War broke out, Volterra was Senator – he was elected in 1905 – and was one of the more influential Italian scholars. He had published important works in several fields of mathematics and physics. He had introduced the fundamental idea of functional, and proved fundamental results in functional analysis. Volterra had always been interested in applications of mathematics to electrodynamics, hydrodynamics, and geophysics from the beginning of his scientific career. It was only after WW1 that he became interested in applications to biology and economy. His dissertation at the University of Pisa in 1882, under Enrico Betti, concerns hydrodynamics. In the 1890s, he studied tides in lakes, which had been observed and experimentally measured in the Swiss lakes by the Swiss physicist Franc¸ois Alphonse Forel (1841–1912) since 1873. Volterra also collaborated with the astronomer Giovanni Virginio Schiapparelli (1835–1910), director of the Brera Observatory in Milan, in the measurement of the motion of the terrestrial physical poles. These were well-known as the problem of latitudes, since astronomers observed that the latitudes corresponding to points on the surface of the earth changed with time. Volterra studied this problem in a series of papers published in Atti dell’Accademia di Torino in 1895 and explained the phenomenon by a mechanical analogy – he used the equations describing a not completely rigid system. In 1897, Volterra created the Italian Society of Physics (Societ`a Italiana di Fisica, SIF) of which he was President in the years 1906–1907. In 1906 he became involved – together with Valentino Cerruti (1850–1909) and Stanislao Cannizzaro (1826–1910) – in the reorganization of the Polytechnic Institute of Turin. On this occasion, he emphasized the necessity of founding higher technical schools primarily devoted to applications. In a speech held in Senate (19 June 1906) Volterra pointed out how Italian industry was mainly related to engineering studies. Volterra explained that industry and technical studies influenced each other, so that teaching had to inform students about industrial development and support it (see [35]). In 1907, Volterra embarked on another scientific enterprise, the foundation of the Italian Society for the Progress of Science (Societ`a Italiana per il Progresso delle Scienze, SIPS), of which he became president until 1909. This Italian Society was inspired by “similar organizations already existing in England and France”, as
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Giovan Battista Guccia (1855–1914) wrote to Volterra in a letter dated 15 February 1906.4 It was an interdisciplinary Society advocating the advancement and the popularization of science. The SIPS soon showed a great interest in applications of mathematics. The Society was divided into 14 disciplinary sections, including electro-technics, chemistry and its applications, anatomy, statistics, geography, geology. . . In addition, Volterra used SIPS as a starting point for other scientific and institutional enterprises in the pre-war period. Federigo Enriques (1871–1946), a prominent figure of the Italian school of algebraic geometry, was enthusiastic about Volterra’s ideas and supported SIPS from its foundation. In 1907, when he was president of the Italian Society of Philosophy (Societ`a Filosofica Italiana, SIF), Enriques organized the second Congress of this Society in Parma, where the constitutive Congress of SIPS took place. Philosophers and scientists were then symbolically put together in trying to popularize their knowledge. But not every Italian scholar shared Volterra’s opinions about organization of science. Guccia, the founder of Circolo Matematico di Palermo, disagreed on the appropriateness of creating the SIPS. The Circolo Matematico was an international society of mathematicians and its journal, the Rendiconti, was one of the most important mathematical journals of the time. Its vocation was therefore very different from the aims of the SIPS, which tried to popularize science and to gather teachers and scientists of several disciplines. Volterra had asked Guccia to support the SIPS and its ideals, but the Director of the Circolo Matematico always proved skeptical. Guccia’s idealistic vision of science, well expressed in the foundation of Circolo Matematico, was probably in contrast with the nationalist purposes of Volterra’s Association. Guccia indeed wrote to Volterra on 30 June 19065 : Well then, according to me, the praiseworthy attempt of an Italian Association for the progress of Science is destined to abort, or at the very least follow the same fate of that which died in 1875 with the Palermo congress, in which the most eminent men of Italy convened and in which wonderful speeches were uttered, full of promises for the future of the association, but that, unfortunately, contained . . . politics: a microbe that in Italy enters throughout and . . . kills everything!
Another institution was the Comitato Talassografico Italiano, founded in 1910, which represents one part of Volterra’s great project to forge a stronger link between science and the industry, as he stated when he was the President of the SIPS. The main purpose of the Committee was to test the quality of Italian seas by using chemical and biological tests in connection with naval industry and fishing, and the quality of the high atmosphere in connection with air navigation. Volterra was the vice-president of the committee from 1910 to 1925 – the president was the Minister of Navy. See further information in [53]. Another consequence of the SIPS was the foundation of a new National technicalscientific Committee in Milan aiming to strengthen the relations between technique
4
Volterra’s Archive, Accademia dei Lincei
5
Quoted in [23], pp. 155–156.
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and science. This Association was organized by Giuseppe Colombo (1836–1921) the Director of the Polytechnic Institute, a politician – who was the founder of the company Edison, now an energy giant. This Committee can be seen as a response to the SIPS agenda: to create a tight connection between universities and industry as a way to increase Italian economic and politic power. The institutions mentioned above changed their terms of reference during the war. The Comitato Talassografico as well as Colombo’s technico-scientific Committee engaged into the war effort. The latter gave remarkable contributions to war work – during the War the experimental Laboratory for building materials of the Polytechnic Institute made more than 100,000 tests, and worked as the official laboratory of the Milan Division of the Technical Direction of the Air Force, but also worked for the Navy, the Battalion of aerostats (balloons), the Rome Aeronautic plant, the Commission for field kitchens, the Army Service Corps, and so on (see [15]). Another important institution founded during the pre-war period, which became more and more important with the War, was the Central Institute of Aeronautics (Istituto Centrale Aeronautico, ICA). The ICA was founded by an officer, Arturo Crocco (1877–1968) in 1908, with the decisive help of Volterra. The first courses of Aeronautics in Europe were given there, closely followed by those of the Ecole Nationale Sup´erieure d’A´eronautique et de Construction M´ecanique created in Paris in 1909 by the Colonel Jean-Baptiste Roche (1861–1954) with the help of Painlev´e. Already by 1903 a wind tunnel had been built in Italy under Crocco’s supervision – at the same time as an English counterpart – for the first time in Europe. In 1906, Crocco – together with Ricaldoni and Munari – built the first experimental dirigibles. In 1908, the first Italian military dirigible (the so-called P.1) was built in plants for aeronautic constructions in Vigna di Valle near Rome. The main constructors were Crocco for the theoretical and Ottaviano Ricaldoni (1877– 1965) for the technical aspects. The building was based on studies of a hydroplane, built and experimented by Crocco himself. In 1914 Crocco built his second wind tunnel, which turned out to be far better than the previous one – with velocities up to 200 km/h – and which remained in function until 1935, the year in which Crocco supervised the construction of Guidonia, the so-called air town. Volterra’s relationship with Crocco seems to have been quite friendly. He has already been a clever experimenter long before the beginning of the war. In 1911, Volterra had been engaged in a Commission for improving air navigation, as the following letter from the Minister of War to Volterra shows (dated November 1911; Cartella VI, Volterra’s Archive, Accademia dei Lincei): I am glad to inform you that, based on a proposal made by myself and the Minister of Navy, by the Royal Decree dated 22 October 1911, registered by the State Audit Court on 15 November, you are called to take part in the Commission for air navigation, whose president is lieutenant-general Giuseppe Valleris. By giving you the news of your appointment, I express my full hope that you will give your strong and deep scientific contribution to the research the Commission will be required to do.
Chapter ♦ 5
Volterra and Italian Interventionism Between 1914 and 1915
When the First World War broke out in 1914, Italy decided to remain neutral. Italy entered the war only on 24 May 1915, and the aim of the present section is to explain what happened in Italy in the interval. The debate between pacifists and interventionists of various tendencies was very passionate – at least among intellectuals and politicians. Historical studies show that the majority of the Italian people did not feel concerned with the war. Italy was in a strange position. It had accepted to sign the military partnership treaty with Germany and Austro-Hungary in the 1880s, and hence it was officially a member of the Triple alliance. However, a secret agreement with France, signed in 1902 by Prinetti and Barr`ere, guaranteed Italian neutrality in case of a German aggression against France. In fact, in 1914, after the beginning of hostilities, the country remained very hostile to any participation in the war. Contrary to what Volterra’s letters seem to declare, the Italians were not clearly in favor of an intervention on the side of the Entente. France was an irritating neighbour: its support in the battle for Independence during the 1860s had been reluctant and pricey (France had then annexed Nice and the Savoy) and this is one reason why Italy had felt obliged to enter the Triple Alliance. Of course, Italy did not feel any friendlier towards Austrians which they had driven out 40 years ago, and who, after 1870, had kept the terre irredente in their lap (the Trentino, the east coast of Adriatic sea including Trieste and Fiume, all considered as Italian because of their important Italian settlements). The treaty only obliged Italy to engage in war on the side of the Central Empires in case these have been attacked. Giving as a pretext that Austria had declared war on Serbia, the Italian government decided that the country could remain neutral. The neutrality lasted until 23 May 1915, when Italy officially engaged in the war on the Entente side. In the meantime, there was an amazing period of bargaining during which both sides had tried to attract Italy to their cause. Basically, the deal was clear: Italy, if it were to become engaged in a war, would choose the side that offered the best chances to recover the terre irredente. At first glance, such a reward could hardly have been expected from Austria, but Germany may have pressured its weaker ally to accept the bargain (and it did in fact apply such pressure). On the other hand, the
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Allies could have promised the Trentino or the Dalmatia coast, but the price they would exact was uncertain. Soldiers who were in Piemonte at the beginning of 1915 stated that until the last moment they had not known which direction they would have had to march if the war broke out: east or west. The game played by the main Italian leaders, San Giuliano, Giolitti, Salandra and Sonnino during this incredible period is described in detail in [51, 38]. Much more plausible than Volterra’s exaggeration of the positive state of opinion towards the Entente was San Giuliano’s comment in a letter to the Italian ambassador in Paris on 12 August 1914: In Italian public opinion, there are three tendencies: the strongest is for neutrality; a very weak one would like us to assist our present allies; another stronger one would be in favor of an attack against Austria despite of the treaty with the Triple Alliance, but this view is cooled and made suspicious by the fact that, despite of their naval superiority, France and England have still not attacked the Austrian fleet. I do not think that there are very active sympathies for France but the moderation of France before and since the beginning of the war has made an optimal impression. On the other hand, there are no antipathies against Germany but there is a great disapproval of her behaviour. There exists very deep aversion against Austria. Our information does not show that if we had marched with Germany and Austria there would have been a revolution. Surely the Italian people would have fulfilled its duty with patriotism but also quite unwillingly.
Why did many intellectuals support the intervention? As already shown in ♦ 3, many of them had a nationalistic attitude: they had supported Italian colonialism and the wars against Turkey and Libya. They feared that Italy could not be considered as a Great Power any more if it did not enter the War. In this case, not only would Italy not have obtained the terre irredente; in addition, its colonial policies would also be stopped. If one reads the Italian newspaper Corriere della Sera of that period, this point of view is clearly expressed and supported. Intellectuals had another reason for supporting the intervention of Italy in war. Interventionism was seen as a progressive and anticlerical attitude opposed to neutralism, which was constantly supported by the catholics (and obviously also by the very leftist parts of the political scene). As representatives of this viewpoint, we mention Giovanni Papini, Giuseppe Prezzolini, Filippo Tommaso Marinetti, Enrico Corradini. According to them, war was connected to an idea of progress by causing a deep cut with the past. The art movement Futurismo had indeed been founded and developed by these intellectuals. “The war is the only hygiene of the world”, as they wrote about the battle of Tripoli in 1909, and the futurist poem, Ode alla violenza (Ode to violence), was published in 1912.6 Volterra had tried to improve cultural and institutional relations between Italy and France from the very beginning of his scientific career. Volterra’s attitude also had a political meaning as he was one of the few intellectuals opposed to Italian colonialist policies; as mentioned in ♦ 3 , the Triple Alliance was used by Italy as an opportunity to start its colonial conquests. Volterra had feared that the Balkan 6
A large overview on Italian intellectuals and the First World War is in [30].
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wars of 1911–1912 could degenerate into a world conflict. This is why he – at least in private – was opposed to the colonial war against Libya. On 17 October 1912, he wrote to his wife from the United States, where he was giving a series of lectures: “I am very worried by the news of the war in the East. It is an enormous danger for Europe. A little beginning of fire is enough to cause a great fire in Europe. The war of Italy against Turkey was a first spark, now the fire is in the East. Let us hope that it will not spread.”7 As his lucid words show, at least before 1914, Volterra disliked wars. Griffith C. Evans (1887–1973), who did research with Volterra in Rome in the years 1911– 1912, wrote to him on 3 October 1914: “I hope that in Rome the weather is fine and that there is not too much anxiety about the war. I know that you do not like wars much.” In 1914 Volterra used his political, scientific and social relationships as an instrument for strengthening the support for the intervention of Italy in the war. The exchange of letters with his French correspondents do not leave any doubt about Volterra’s position in favor of the intervention. While Volterra’s position was shared by many Italian scholars, some differing voices emerged. Tullio Levi-Civita (1873– 1941) had a neutralist position, and expressed his pacifism whenever there was an occasion.8 Levi-Civita was indeed a socialist and the Socialist Party was firmly neutralist. Also Francesco Severi (1879–1961), one of the leading figure of Italian algebraic geometry, at that time Levi-Civita’s colleague at the University of Padua, was a socialist; but he openly expressed another position in favor of intervention with the Entente and, as a consequence, he was expelled from the Party. Another example is given by Corrado Segre (1863–1924), professor of geometry in Turin and the founder of the so-called Italian school of algebraic geometry; though a neutralist, he was said to have sympathies for Germany – a judgement which is expressed by Carlo Somigliana (1860–1955) in a letter to Volterra (dated 15 May 1916).9 And he was not the only one at the Faculty of Sciences of Turin who showed such an attitude. As Somigliana wrote: “Unfortunately, people of our Faculty are of that kind; and Segre more than the others. The predominant idea is that we have to live in the limbo of the Fathers, ignoring the war and with no dislike or sympathy towards anyone, except the due respect towards Germans.” Opinions similar to Segre’s were expressed by other scientists – physicists, biologists, chemists, astronomers. Many of them had spent a period of specialization in Germany, where they had met German colleagues and had kept in touch with them. For instance, Giacomo Ciamician (1857–1922) studied at the University of Giessen and had been nominated for the Nobel prize in Chemistry. He wrote a letter to Volterra on 6 August 191410 in which he took a position against any kind of
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Quoted in [23], p. 175.
8
On Levi-Civita’s pacifism, see the correspondence between Levi-Civita and Birkhoff, in [44]. Here, Levi-Civita wrote that “imperialism” is the actual enemy of people. 9
Contained in Volterra’s Archive, Accademia dei Lincei.
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Volterra’s Archive, Accademia dei Lincei, Rome.
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nationalism and in favor of a neutralist position, since war had to be considered a “crime against humanity”. He asked Volterra to assume a position against the intervention of Italy and, in addition, to convince foreign scholars that this war was a madness. He explicitly wrote: “Let us hope that at least Italy shall remain neutral.” Even among those who were not hostile to the intervention with the Entente, there were scholars who went on professing a great respect for German culture. An example is given by Camillo Golgi (1943–1926), who in 1906 won the Nobel prize in medicine and physiology for his discoveries on the nervous system. In 1916, he held a lecture at the Congress of SIPS where he invited Italians to fight against Germany while continuing to adopt German technology and a German-style educational system. The heated discussions about the intervention in the war left deep scars on Italian society. The following letter, written by the Turin astronomer Giovanni Boccardi (1859–1936) to Maurice Fr´echet on 23 December 1920, provides a clear hint of the resentments felt by some Italian academics in relation to how things had been going during the war. [A]lmost all the professors of mathematics (above all the astronomers and geodesists) from our country have been affected by the war, they would never have wanted it against their former allies. You had a proof of that at the Congress in September.11 The Germans had sent a protest against the organizers of the Congress, asking not to join the congress, because the Germans were excluded. Well, my dear colleague, there was only M. Volterra, on assignment from the Government, who had come out of necessity. Myself I came because France is my second homeland. In Germany, I shall not go anymore. I have had enough of Berlin and Hamburg! Will you believe that, as soon what I had done and said in Strasbourg had been known, I received letters from everywhere which condemned my behavior and urged me to follow the tedescofili (!), as I am almost the only one to hold a grudge against Germany. . . ? Can you realize that among the supplicants there are field officers from the army and the navy! After that I understand Caporetto and all the other things! I have written on the subject to M.E. Picard, who was saddened by all this. What can I do? If I were 40 years old instead of 61 1/2, I would change my nationality; but now it is too late! I must be resigned to have almost all my colleagues against me, and to see myself excluded from all their Academies and Commissions. If only my dear French colleagues were to realize the painful truth I had the honour to present to you!
11
Boccardi refers to Strasbourg congress of Mathematicians in September 1920.
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Emile Borel ca. 1920
Jacques Hadamard ca. 1910
Vito Volterra ca. 1920
Emile Picard ca. 1910
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Vito Volterra’s house in Ariccia (near Rome). ca. 1920
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c Accademia dei Lincei Volterra’s draft of a letter to Borel, 24 October 1914
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c Accademia dei Lincei Picard’s letter to Volterra, 25 January 1915
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Vito Volterra ca. 1920 as Dean of Rome Mathematical Faculty
Dirigibles M.1 and M.2 in Vigna di Valle, 1912
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Institut de France in Paris, ca. 1910
Louvain University Library, September 1914
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Joseph P´er`es, ca. 1940
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Volterra (Rome, 1930s)
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Borel to Volterra Paris, 3 September 1914 Mon cher ami, ´ e´ tres ` sensible a` votre souvenir que m’a transmis M.Appell.12 J’ai et L’attitude de l’Italie est une des raisons objectives que nous avons de penser ´ que nous defendons la cause de la civilisation, de la liberte´ et du droit, ce qui nous donnera la force de lutter jusqu’au bout, sans nous laisser abattre ´ ´ ` par aucune epreuve, car le temps assurera forcement notre succes. ´ Veuillez presenter mes hommages a` Madame Volterra, ainsi que les meilleurs souvenirs de ma femme et croyez a` ma bien cordiale et bien ` amitie. ´ sincere Emile Borel ´ ees ´ Mme Appell et ma femme sont decid a` ne pas quitter Paris.13 Pour ´ ´ ce que j’ignore mon compte, je le le quitterais que si j’etais appele´ a` l’armee, pour le moment.
12
The mathematician Paul Appel (1855–1930) was Borel’s father in law. Appel was a typical representative of the generation who experienced the trauma of the French defeat of 1870, especially because he was born in Alsace. His memoirs (Souvenir d’un Alsacien, Payot, 1923 – available on Gallica) give an interesting insight of how he faced the World War and the following years in a rather different way than Emile Picard who was almost the same age.
13
The beginning of the war was a hard time for the Entente. After an awful month of August 1914 on the French side, the French army was almost defeated. German armies were marching on Paris and were very close to catching the French and British armies in a pincer movement. The powerful counter-offensive decided on by Joffre (known under the name of (first) battle of the Marne) between September 6th and 12th suddenly stopped German progress, forcing them to withdraw to the Aisne River a hundred kilometers northwards. Then began another dramatic and bloody period of 3 months, the race for the sea, where both sides tried to overtake the other in the remaining open space between the front and the English Channel. At the beginning of 1915 a continuous front was stabilized between the Channel and the Swiss border. It lasted without major change until 1918. L. Mazliak, R. Tazzioli, Mathematicians at war, Archimedes 22, C Springer Science+Business Media B.V. 2009 DOI 10.1007/978-90-481-2740-5 6,
35
36
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Volterra to Picard Ariccia (Roma), 7 September 1914 (draft) Monsieur et cher Ami Les lettres maintenant emploient beaucoup de temps pour arriver et ` que plus ou moins en retard quelquefois elles n’arrivent pas, mais j’espere ` aussi que vous aurez rec¸u de mes nouvous recevez cette lettre. J’espere velles. J’en ai rec¸u indirectement de votre famille et j’ai su que vos fils et votre ` ligne a` la guerre.14 gendre ainsi que le fiance´ de votre fille vont en premiere Je fais les meilleurs vœux pour eux. Vous savez mon attachement a` votre noble et grand pays, qui lutte pour la cause de la justice et de la civilisation. Tous mes vœux, ainsi que ceux de la plupart de mes compatriotes, vont pour ´ A mon avis depuis longtemps l’Italie le triomphe de la France et de vos allies. ˆ e´ de la France contre l’Autriche et l’Allemagne, en aurait duˆ se placer a` cot ` que sous la pression de l’opinion abandonnant sa position neutrale. J’espere publique cela arrivera. Veuillez compter de ma part et de celle de Madame Volterra tous nos vœux pour vous pour Madame Picard et pour toute votre famille. Veuillez accepter, mon cher Ami, l’expression de mon plus profond attache´ ment et de tout mon devouement
Volterra to Borel Ariccia (Roma), 14 September 1914 Mon cher Ami, ` lettre, ainsi que celle de M.Appell. La Je viens de recevoir votre chere ´ correspondance arrive maintenant avec un enorme retard. ´ ´ J’ai ete heureux de recevoir vos bonnes nouvelles, ainsi que celles de votre famille. ´ ` et les vicLaissez-moi vous faire toutes mes felicitations pour les succes toires de la France contre l’invaseur.15 Je ne doute pas, commeje n’ai jamais
14
Volterra refers to Picard’s son-in-law Louis Dunoyer, see footnote 20 , and to the physicist Jean Villey (1885–1948) who later married Picard’s daughter Suzanne. Villey was appointed professor at Paris University in the 1930s. During the Occupation, in 1941, he was arrested for having handed out pamphlets against the Government: in the Journal Officiel from 18 October 1941, one finds a decree by the minister of Education J. Carcopino striping him from his position.
15
This letter is written just after the end of the battle of the Marne. See footnote 13.
Mathematicians at war
37
doute´ un seul instant du triomphe de votre noble et grand pays, que j’aime de tout mon cœur avec le plus profond attachement. La France lutte pour la justice et la liberte´ et pour la cause de la civilisation contre la violence de ´ l’imperialisme le plus brutal et le plus odieux qui voulait asservir l’Europe. ˆ abominable va s’evanouir. ´ Mais ce reve L’acte par lequel les deux empereurs ´ ´ e´ un crime horrible. Tel est le jugement allemands ont dechaˆ ıne´ la guerre a et que j’en ai fait, et l’opinion de la majorite´ de mes compatriotes. Tel sera je ˆ de l’histoire. pense l’arret ˆ et la mission de l’Italie est de se placer a` cot ˆ e´ de la A mon avis le role ´ contre l’Autriche et l’Allemagne en abandonnant la France et de ses allies ´ neutralite. ˆ Voila` mon vœu le plus chaleureux. Puisse-t-il etre accompli. Puissent nos ˆ deux pays Latins se rapprocher toujours davantage et etre toujours unis contre les ennemis communs. ´ Veuillez bien presenter tous mes hommages a` Madame Borel et veuillez accepter, mon cher Ami, les salutations les plus affectueuses et l’expression ´ de la plus vive amitie´ et de tout mon devouement. Vito Volterra Je viens de recevoir une lettre de M.Gateaux16 qui est a` la guerre. Elle ´ Pouvez-vous me donner des nouvelles de M.Per ´ es, ` 17 m’a beaucoup touche. 18 19 ´ de M.Boutroux, de M.Paul Levy ? Il y a tant d’amis dont je voudrais avoir des nouvelles!
16
Ren´e Gateaux (1889–1914), a young French mathematician who had begun a thesis on functional calculus and spent the academic year 1913–1914 in Rome to study with Volterra. Called to the army at the beginning of the war, he was killed on 3 October 1914. Gateaux’s biography and comments about his surprising mathematical destiny can be found in Laurent Mazliak: Les fantˆomes de l’Ecole Normale, in [22].
17
On P´er`es, see ♥ 7 .
18
The mathematician Pierre Boutroux (1880–1922) was the son of the famous philosopher of science Emile Boutroux. In parallel with his mathematical work on differential equations, he was involved in questions on philosophy and history of science. See [41].
19 Paul L´evy (1886–1971), who became after the war one of the major specialists in probability theory of the 20th century, had defended a thesis in functional calculus applied to potential theory in 1911 in Paris. The publication of a series of lectures on functional analysis after the war was an essential source for Wiener’s works on Brownian motion. L´evy’s huge correspondence with Fr´echet, that lasted almost 50 years, has been published in [6].
38
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Picard to Volterra Paris, 25 September 1914 Cher ami, ´ e´ si deprim ´ ´ J’ai et e´ tous ces temps-ci que je n’ai pas repondu encore ` aimable lettre du 5 Sept. Je vous remercie bien vivement de a` votre tres vos vœux chaleureux pour le triomphe de la France sur des barbares, dont la conduite rappelle les invasions d’autrefois. L’Allemand, je l’ai tou´ n’est civilise´ qu’en apparence; dans les plus petites choses, jours pense, il est grossier et sans tact, et le plus souvent un compliment d’Allemand ´ ` e´ native, et vous avez les est une gaffe enorme. Amplifiez cette grossieret horreurs que nous voyons. De plus il manque de franchise et se sert d’une enveloppe philosophique pour excuser ses crimes; il est temps que cet ` orgueil immense soit abattu et que l’Europe puisse respirer pour un siecle. Toute l’Europe devrait se soulever contre ces nouveaux Vandales qui ne songent qu’a` mettre toutes les nations a` leurs pieds. ´ Comme vous le savez, quatre des miens sont aux armees. Le fiance´ de ma seconde fille a rec¸u quatre balles dans la cuisse et se remet lente´ ´ ment. Mon gendre Dunoyer a tout recemment rec¸u un grand nombre d’eclats d’obus, mais n’est pas en danger; il combattait, comme lieutenant, autour de Nancy.20 Mon second fils a assiste´ a` la grande bataille de Charleroi;21 dans la retraite il fut pris de dyssenterie et est encore en convalescence. ´ Inspecteur des Finances, est valide. Que m’apportera Seul mon fils aˆıne, ` longue, mais nous irons jusqu’aux derniers demain? Cette guerre sera tres sacrifices. Ma femme, mes filles, et mes petits enfants ne sont pas a` Paris. Ils ont trouve´ l’hospitalite´ a` Avignon chez unesœur de mon gendre. Ils avaient
20
For the military context, see footnote 13. Louis Dunoyer (1880–1963) was a physicist educated ´ at the Ecole Normale Sup´erieure (1902–1905). He received the grade of doctor e` s-sc. physiques in 1909 under Mascart and Langevin. Dunoyer is known for his inventiveness in physical instrumentation as well as his great experimental skill. He invented the first electromagnetic compass (1907– 1908), which was used by Charles Lindbergh for the first nonstop solo flight across the Atlantic from New York to Paris in 1927. Dunoyer was subsequently a lecturer (1920), then professor, at the Institut d’Optique at the Sorbonne (1926–1939), and a physicist at the Paris Observatory (from 1927). In 1906 he married Picard’s daughter, Louise.
21
Between 21 and 23 August, the French troops tried to stop the German offensive in Belgium, but were severely defeated and had to withdraw in the Ardennes. On 24 August, Lille was declared an open city that is, that France could not defend it and that the invaders should spare the inhabitants.
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´ allemande s’approchait de la capitale.22 quitte´ Paris, en moment ou` l’armee Je suis donc seul chez moi. C’est vainement que je cherche a` travailler; ma ´ est toujours sur les champs de bataille. Nous avons cependant a` pensee ˆ e´ de faire de des œuvres utiles. Il y a a` l’Institut un Ouvroir ou` l’Institut tach ´ cent trente femmes travaillent a` faire des choses diverses pour les blesses ˆ de Thiers,24 qui nous appartient, et les soldats.23 De plus, dans l’ancien hotel ˆ nous avons installe´ un hopital, sous la direction de nos grands chirurgiens, ´ des blesses ´ gravement atteints. La ville de Paris, quelqueou` sont soignes ´ comme leg ´ ere ` et frivole, est d’une admirable gravite. ´ La confois regardee ` grande, et chacun s’efforce, dans la mesure de ses moyens, fiance est tres ´ ´ de concourir a` la defense nationale. Et dire que ces miserables, pour qui ´ l’espionage et le mensonge sont le besogne courante, ont represent e´ Paris ´ ´ en revolution et en etat de guerre civile!25 J’ai transmis a` ma femme la carte si touchante de M.me Volterra. Je l’en remercie vivement, et je vous envoie, bien cher ami, avec tous mes remer` ciements pour vos vœux, l’assurance de mes sentiments tres affectueux, Emile Picard
22
See footnote 20.
23
In his celebrated book Souvenirs d’un alsacien 1858–1922 (Paris, Payot, 1923), Appell wrote about the Institut de France during the War (pp. 274–275): “The Institut opened in the hˆotel Thiers [see footnote 24], place Saint-Georges, an auxiliary hospital organized and perfectly ruled by our colleague M. Fr´ed´eric Masson: a second hospital had been created in Chantilly. Here in Paris, in order to give work to poor women, the Institut created a sewing room under the clever and alert direction of M.me Vallery-Radot.” 24 In 1905 the hˆ otel built for Thiers in Paris was donated to the Institut de France by one of his heirs. In 1880 it had been transformed into a library. During the war, it became a military hospital (see footnote 23). The list of doctors and nurses can be found in Fr´ed´eric Masson, Inauguration a` l’Hˆotel Thiers le samedi 5 novembre 1921 d’une plaque comm´emorative des soldats morts pour la France a` l’Hˆopital de l’Institut (1914–1915), Typ. de Firmin-Didot, Paris, 1921. 25 Interesting testimony about Paris during the first weeks of the war can be found in Arthur-L´evy’s book 1914, Aoˆut, septembre, octobre a` Paris, Plon, 1917. The author mentions some actions from German propaganda (dumping of pamphlets from planes, in particular) to encourage the Parisian population to capitulate at the beginning of September. In the book, one may observe a slight criticism of how the French Government, scared by the quick motion of the German Armies, decided to leave Paris. On the subject, see also M´emoires du G´en´eral Galli´eni. D´efense de Paris. 25 Aoˆut–11 Septembre 1914, Payot, 1920.
40
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Borel to Volterra Paris, 16 October 1914 Universite´ de Paris 26 ´ Ecole Normale Superieure 45, rue d’Ulm Mon cher ami, Vous avez sans doute lu l’appel adresse´ par les intellectuels allemands ´ ´ 27 Je desirerais publier dans la Revue du Mois28 quelquesau monde civilise. ´ ´ unes des appreciations ou reponses relatives a` cet appel, dues a` des neu´ erable, ´ ´ a` tres. Il me semble qu’il serait pref si possible, d’avoir des textes dej ´ dans les pays neutres, et non pas ecrits ´ ´ publies specialement a` l’instigation de franc¸ais ou d’anglais. Pourriez-vous me signaler et me procurer au besoin des textes de ce genre parus en Italie. Nous voyons bien ici quelques journaux italiens, mais ´ ` ´ de nous borner pas toujours reguli erement et nous sommes parfois forces a` y lire des nouvelles directes de la guerre de source allemande et autrichi´ ` enne, qu’il est toujours interessant de connaˆıtre, mais qui ne nous enlevent ` de notre cause. pas notre confiance dans le succes 26
Let us recall that Borel had been adjoint-director of the Ecole Normale Sup´erieure since 1910. After the war, extremely affected by the atmosphere of the institution in mourning due to the heavy losses of the war among the students, Borel resigned from this position. See footnote 330. 27 On 4 October 1914, 93 German intellectuals signed an open letter to the “civilized world” (Kulturwelt), with the official aim of protesting against what they considered as slanders about Germany in the newspapers of the Entente, after the failure of the German original plan. The letter, cleverly written by the writers Ludwig Fulda, Hermann Sudermann and Georg Reicke, rejected all the responsibility of the war on the Entente and presented German reaction as a mere defensive one. Among the signatories were many renowned scientists, including Planck and Roentgen. This was the first intervention of intellectuals during the war, and its impact was enormous, in particular in neutral countries. In France, the reactions were violent (see footnote 174), but also anxious about how the manifest would be received among the neutral countries. On the behavior of intellectuals during WW1 (in particular on the Manifest of the 93) see C. Prochasson: Les Intellectuels, in [4]. 28
The Revue du Mois was the monthly journal founded by Borel and his wife in 1906 after Borel was awarded the Petit d’Ormoy Prize. Camille Marbo, in her memoirs ([39], Chapter VIII) discusses the creation of the journal. Until 1915 (the journal stopped its publication when Borel’s right-hand man was killed at the front and Borel went to the army), the Revue du Mois appeared as a beacon among cultural publications in France. Borel asked many of the most prominent representatives of the intellectual life to write papers for the journal. Among them were obviously numerous scientists. Mathematicians as Volterra, Poincar´e, Picard, Painlev´e . . . and of course, Borel himself; Physicists such as Jean Perrin; Biologists such as Le Dantec with whom Borel had a controversy about randomness in science. There were historians, economists, writers, artists . . . The whole run of the journal offers a magnificent picture of intellectual life in France in the years preceding WW1. On the subject, the reader may consult [41, 26]. La Revue du Mois is supposed to be available in 2009 at the electronic library Gallica.
Mathematicians at war
41
´ Veuillez presenter mes hommages a` Madame Volterra et croire a` mon ´ ´ amitie´ bien devou ee. Emile Borel
Volterra to Borel n.p., 24 October 1914 Mon cher Ami, ` ` lettre du 16 Octobre et je m’empresse Je viens de recevoir votre tres-ch ere ´ ´ a` vous repondre. Je vous ai ecrit vers la moitie´ de Septembre une lettre ou` je ´ es, ` de M.Boutroux, vous demandais des nouvelles de M.Gateaux, de M.Per ´ et d’autres jeunes amis Franc¸ais. Je n’ai rec¸u aucune reponse et comme ´ e´ perdue. A un vous ne faites aucune allusion a` cette lettre, elle doit avoir et ´ mois de distance je ne peux que confirmer ce que je vous ecrivais alors, c’est ´ ` de la France, ma plus vive sympathie a` dire mes felicitations pour les succes pour votre noble pays qui lutte pour la justice et la liberte´ et pour la cause ´ de la civilisation contre la violence du plus brutal et odieux imperialisme. Je ˆ de l’Italie est, a` mon avis, celui de s’unir a` la triple vous disais que le role entente. Je puis ajouter aujourd’hui que la confiance dans cette union n’a fait qu’augmenter, car la sympathie pour la France l’Angleterre et la Russie ´ ets ˆ au s’est accrue chez nous. D’autre part la persuasion que tous nos inter point de vue moral ainsi que politique sont en opposition avec l’Autriche et l’Allemagne n’a fait que se raffermir. ´ ´ a` publie. ´ Je vous envoie un Vous avez raison de desirer un article dej ` article remarquable qui a paru dans la “Tribuna”29 du 6 Octobre, le jour apres celui ou` l’appel des savants allemands a paru. L’article est signe´ “Rastignac” ` connu dans notre monde litteraire ´ et c’est a` dire Vincenzo Morello30 tres ´ ` un des meilleurs ecrivains parmi les journalistes Italiens. Il est aussi tres ´ e´ comme auteur dramatique. appreci Je crois que l’article de Rastignac est justement ce que vous cherchez et ce qu’il vous faut. Je chercherai cependant s’il y en a aussi d’autres qui pourraient vous convenir. 29
The newspaper La Tribuna was founded in Roma in 1883 by members of the opposition at the Italian Parliament.
30
Vincenzo Morello (1860–1933) was journalist, writer and dramatist; he became senator in 1923. Under the pseudonym of Rastignac he signed several polemical articles (often against politicians). He collaborated with La Tribuna and founded the newspapers Il Giornale together with Bobbi and Bellodi in 1894 and LOrain Palermo in 1908, and the journal Cronache letterarie in Florence in 1909 which collected article of the main writers of the time. Morello later supported Benito Mussolini in his ascent to power.
42
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Nous avons eu une foule d’articles de toute sorte qu’on a appele´ la “polemica nazionale”31 sur la question de la guerre et beaucoup de protestations contre les barbaries des allemands, leurs violations des conventions ´ ainsi que sur les destructions qu’ils ont accompli de la Haye et des traites ´ des Univeren France et en Belgique. A ces protestations se sont associes ´ des Academies ´ sites des hommes politiques des savants etc. J’ai toujours ´ e´ a` ces protestations mais il est presque impossible de suivre et de adher ´ recueillir toutes ces protestations qui sont repandues un peu partout dans les journaux de Rome et de la province et qui ont paru la plupart sous la ´ egrammes ´ forme de tel et d’ordres du jour. ´ e´ tres ` fet ˆ e´ chez nous. Ses Vous savez sans doute que M.Richet32 a et ´ ´ et, ˆ ont eu un conferences, auxquelles j’ai assiste´ avec beaucoup d’inter ` et un grand nombre d’auditeurs. Il a aussi tres ` bien reussi ´ grand succes ´ ´ e´ dans la polemique contre l’appel des savants allemands. Nous avons adher a` ses protestations. ˆ ` de la France et de Vous avez parfaitement raison d’etre sur ˆ du succes ´ Tout le monde civilise´ est contre l’Autriche et l’Allemagne. ses allies. Je suis parmi ceux chez nous, qui sont les plus impatients de sortir de ´ mais je ne doute pas que meme ˆ la neutralite, ceux qui ont un peu moins ˆ ´ d’impatience ne peuvent pas manquer d’avoir les memes esperances et les ˆ memes aspirations que moi. ˆ Mon vœu aujourd’hui est le meme que celui que j’ai fait depuis le com´ doivent etre ˆ mencement de la guerre. L’Italie, la France et ses alliees unies ´ contre l’ennemi qui a accompli le crime de dechaˆ ıner la guerre et qui voulait asservir l’Europe. ´ Veuillez presenter tous mes hommages a` Madame Borel. Madame Volterra lui avait envoye´ un mot dans ma lettre de Septembre pour lui exprimer ´ ´ et les son amitie´ et sa sympathie pour son devouement pour les blesses malades.33 Veuillez bien lui confirmer ses sentiments. Veuillez accepter, mon cher Ami, l’expression de toute mon amitie´ et de mon plus profond attachement. Vito Volterra 31 Contrary to what Volterra writes, it is not clear that the expression polemica nazionale had been widely used in Italy to describe the fierce discussions between the intellectuals about the Italian neutrality. On the subject, see ♦ 5 32
Charles Robert Richet (1850–1935) was a French physiologist. His work on anaphylaxis (the reaction by a sensitised individual to a small-dose injection of an antigen) won him the Nobel Prize for Physiology or Medicine in 1913. He was also very fond of spiritualism. After the war, he adopted racist and eugenist ideas exposed in his book La s´election humaine published by Alcan in 1919. On Richet during WW1, see in particular Ilana L¨owy: La recherche m´edicale pendant la grande guerre: les trajectoires contrast´ees de Charles Richet et d’Alexis Carrel, in [3], pp. 123–133. 33
Marguerite Borel (Camille Marbo as a writer) had actively participated in the creation of a committee to relieve the sufferings caused by the war. In her autobiography [39], she describes her action. Hospitals were placed in several academic buildings in Paris, including the Ecole Normale Sup´erieure (where it was supervised by the mathematician Elie Cartan).
Mathematicians at war
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Volterra to Borel n.p., 29 October 1914 Mon cher Ami, ` que vous aurez rec¸u ma lettre du 24 Octobre en reponse ´ J’espere a` votre lettre du 16 Octobre et le journal que je vous ai envoye´ dans un pli a` part. Je vous envoie aujourd’hui un autre article qui est paru dans le “Messaggero”34 le plus populaire de nos journaux. L’article est de M.Edoardo Cim´ a` l’appel bali35 professeur de Droit International et il est aussi une reponse des intellectuels allemands. ` vous envoyer aussi quelque autre article, J’espere En vous exprimant encore une fois mes vœux les plus chaleureux pour le ` des armees ´ alliees ´ et pour l’union de nos deux pays, je vous envoie succes ´ ` l’expression de tout mon devouement et de l’amitie´ la plus sincere. Vito Volterra
Borel to Volterra Paris, 4 November 1914 Universite´ de Paris ´ Ecole Normale Superieure 45, rue d’Ulm Mon cher ami, Nous avions bien rec¸u votre lettre de septembre et le mot aimable de ´ Madame Volterra: c’est notre reponse qui ne vous est pas parvenue. Je ne ´ es ` est reform ´ ´ de e´ et est professeur au lycee sais pas ou` est Gateaux36 ; Per ´ ´ il travaille a` Bordeaux au ministere ` Montpellier; Boutroux est aussi reform e;
34
The newspaper Il Messaggero was founded in Rome in 1878; from the beginning it addressed the Roman general public and its director invited Romans to send news concerning the life and chronicle of the city, rewarding them by a half Lira.
35
Edoardo Cimbali (1862–1934) was professor of international law at the universities of Macerata, Sassari and Catania. He was a pacifist and consistently on the side of oppressed people. Among other things, he wrote the book I miei quattordici anni di campagna contro la Triple Allenza, Campobasso, G. Colitti, 1917. 36
In fact, at that time, Gateaux had been dead for a long time (he was killed during the race for the sea on October 3rd, 1914). See Laurent Mazliak : Les fantˆomes de l’Ecole Normale, in [22]. On Gateaux see footnote 16.
44
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
37 ´ ´ de la Republique, ´ de la guerre comme secretaire du Bulletin des armees le journal que le gouvernement envoie a` tous nos soldats. Ceux qui se bat` de nouvelles reguli ´ ` tent sont si nombreux qu’on n’a guere erement que des parents et amis les plus directs; jusqu’ici nous n’avons pas eu de malheurs ´ e´ de meme ˆ ´ eves ` parmi eux. Il n’en a pas et malheureusement pour les el de l’Ecole Normale, qui sont aussi un peu notre famille ; plusieurs jeunes gens ` grand avenir scientifique ont dej ´ a` disparu.38 La responsabilite´ de de tres ´ de la Turquie ceux qui ont voulu cette guerre est vraiment terrible. L’entree ` ˆ ´ en scene va peut-etre amener une extension qui aura pour consequence ´ ´ et de diminuer la somme totale des maux de la guerre.39 d’abreger la duree ´ qui ont la responsabilite´ Mais je comprends fort bien que les hommes d’etat ´ de l’action hesitent a` attirer sur leur pays une partie de ces maux aussi ´ longtemps qu’ils peuvent l’eviter. Je crois que tout le monde s’en rend bien compte ici; la reconnaissance et la sympathie n’en seront que plus grandes ´ ´ ´ pour les nations qui se joindront a` nous pour reduire definitivement a` neant ˆ de la domination prussienne sur le monde entier. le reve ` interessant ´ Je vous remercie de l’envoi du tres article de Rastignac; je ´ vais immediatement m’occuper de le faire traduire en franc¸ais et de le publier. Veuillez rappeler ma femme au meilleur souvenir de Madame Volterra et ´ accepter l’expression de ma plus cordiale amitie.
Emile Borel
37
The Bulletin des arm´ees de la R´epublique (available in digitized form in the electronic library Gallica) was an official publication of the Ministry of War created at the very beginning of the war. In he first issue on August 15th, 1914, the purpose of the journal is explained by the minister Messimy and the President of the Cabinet Viviani: to help the fighting soldiers to measure the importance of their individual efforts by showing a general picture of the situation. At the creation, the publication was a daily paper. It soon became bi-weekly and later weekly.
38
First mention by Borel of the terrible consequences of the war on the students of the Ecole Normale. On the 280 students of the Ecole Normale of the academic years between 1911 and 1914, 101 died at war (see Laurent Mazliak: Les fantˆomes de l’Ecole Normale in [22]).
39
The Ottoman Empire entered the war on October 28th, 1915 on the side of the central empires. It might have remained neutral, as a majority of the cabinet wished, at least until the situation became clearer. But the opportunism of the minister of war Enver Pasa, early German victories, friction with the Triple Entente (France, Russia, and Great Britain) arising out of the shelter given by the Ottomans to German warships, and long-standing hostility to Russia combined to produce an Ottoman bombardment of the Russian Black Sea ports on 29 October 1914 and a declaration of war by the Entente against the Ottoman Empire. See Ottoman Empire in Encyclopædia Britannica, 2008.
Mathematicians at war
45
Borel to Volterra Paris, 9 November 1914 Universite´ de Paris ´ Ecole Normale Superieure 45, rue d’Ulm Mon cher ami, J’ai rec¸u votre nouvelle lettre et le Messaggero.40 Je pense que vous avez ´ bien cette fois rec¸u ma reponse a` l’envoi de la Tribuna41 et a` votre excellente ´ lettre qui nous a fait tant de plaisir. Depuis que vous l’ecriviez, votre min` a et ´ e´ modifie; ´ je pense que si la Turquie prend une attitude reellement ´ istere ´ ets ˆ de l’Italie seront mis en jeu de telle maniere ` que aggressive, les inter ´ ˆ son intervention deviendra necessaire aux yeux de tous. C’est meme la` une ´ ´ raison serieuse pour compter sur la moderation relative de la Turquie, qui se ´ laisse evidemment guider par l’Allemagne.42 ´ Veuillez presenter mes hommages a` Madame Volterra, a` laquelle ma femme transmet son meilleur souvenir, et accepter la nouvelle expression ´ de mon affectueuse amitie. Emile Borel
Volterra to Borel n.p., 30 November 1914 (draft) Mon cher Ami, J’ai l’honneur de vous envoyer un fascicule de la Vita Internazionale43 ou` ´ beaucoup. il y a un article de M.T. Moneta44 qui vous interessera ´ eves ` ´ Je regrette infiniment la mort des jeunes el de l’ecole normale. Com´ erat ´ bien de victimes a fait l’acte scel accompli par les deux empereurs allemands! C’est horrible a` y penser!
40
See footnote 34.
41
See footnote 29.
42
See footnote 39.
43
The journal La Vita Internazionale was created by E.T. Moneta in 1898 (see the following note).
44
Ernesto Teodoro Moneta (1833–1918) was an Italian journalist. Much involved in pacifist movements at the beginning of the 20th century, he was awarded with the Nobel prize for peace in 1907.
46
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Je regrette beaucoup de ne pas recevoir de nouvelles de M. Gateaux45 et de M. Soula46 qui se battent tous les deux. Si par hasard vous pouvez en recevoir je voudrais bien les connaˆıtre. Je fais les meilleurs vœux pour vous et votre famille. Au moment actuel l’invaseur allemand a rec¸u de bien rudes coups par les ´ Il ne fait que se retirer et sa resistance ´ allies. ne pourra pas se prolonger. ˆ par la defaite ´ ´ ` que la bataille de Pologne47 finira bientot de l’armee J’espere allemande orien[ missing page?]48 mande. C’est ce que je souhaite de tout mon cœur. Et je souhaite aussi ´ e´ des ` le premier moment que l’Italie se place du cot ˆ e´ de la ce que j’ai desir triple entente. ´ en campagne de la Turquie a et ´ e´ une nouvelle faute de L’entree ´ erer ´ la fin de son existence sans l’Allemagne.49 La Turquie ne fait qu’accel ´ pouvoir porter une aide efficace a` ses allies. Je n’ai jamais doute´ que les allemands et les autrichiens seront battus. 50 ´ ´ Aujourd’hui mes previsions du premier moment sont en train de se realiser. La civilisation et la justice triompheront sur les barbares. ` affection Veuillez accepter, mon cher Ami, l’expression de ma plus sincere ´ et de toute mon amitie´ et veuillez bien presenter de ma part et de la part de Madame Volterra les meilleurs hommages a` Madame Borel.
45
See footnote 36.
46
Jacques Soula was supposed to benefit from a David Weill grant to go to Rome in the academic year 1914–15, the year after Gateaux (see 16). He had been in contact with Volterra since 1912 as he prepared a thesis about functional analysis, while he was professor of mathematics in Aix-enProvence Lyc´ee. On 11 September 1914 he had written to Volterra to explain that, though he had not been mobilized, he engaged himself as volunteer. In the interesting letters he sent to Volterra from the front, he comments several times about the needed Provenc¸al solidarity between the south of France and Italy. After the war, he became professor of calculus and astronomy at the University of Montpellier from 1921 to 1954.
47
Between September and December 1914, a series of battles (the major ones are Tannenberg and the Mazure lakes) opposed the Russian and German armies. The Russians, more numerous but suffering from inexperience and worse material, were continuously defeated and withdrew towards Poland. Between November 11th and December 6th 1914, an important confrontation opposed the 9th German Army to the 1st, 2nd and 5th Russian Armies in terrible weather conditions around Lodz. The consequence of this battle was ambiguous. The Russians had succeeded in stabilizing the Front ahead of Warsaw but the Germans had succeeded in destroying the Russian plans against Silesia.
48
The text seems discontinuous here and maybe a page is missing. It may be only that Volterra had made a mistake.
49 50
See footnote 39.
It is hard to know exactly why Volterra had written this sentence at this moment of the war. It may be because during the indecisive battle of Lodz (see footnote 47) the victory was successively claimed by the Germans and the Russians.
Mathematicians at war
47
Borel to Volterra Paris, 10 December 1914 Universite´ de Paris ´ Ecole Normale Superieure 45, rue d’Ulm Mon cher ami, ` interessant ´ Je vous remercie bien vivement de l’envoi du tres article de M.Moneta51 ; je dois vous avouer que je ne connaissais point M.Moneta, qui ˆ ` distingue; ´ a-t-il en Italie une situation imporme paraˆıt etre un esprit tres tante? ´ J’ai eu l’occasion de causer assez longuement avec M.Ferrero,52 qui etait ` qu’il y reviendra prochainement venu pour une semaine a` Paris; j’espere avec Madame Ferrero; il a constate´ que la vie de Paris est plus normale qu’il ne le pensait. Nous avons beaucoup parle´ de la bataille de Pologne53 ´ ´ que les Russes pendant qu’elle se deroulait; je n’ai jamais eu la pensee ` decisif; ´ pourraient remporter un succes je suis d’ailleurs, depuis le mois ´ d’aout, ne ˆ convaincu chaque jour davantage que l’immensite´ des armees ` de ces batailles comme Iena ´ permet plus guere ou Sedan dans lesquelles ´ ´ l’un des combattants est aneanti par l’autre. La seule chose que les allies d’Occident puissent demander aux Russes, et dont ceux-ci s’aquittent fort ´ ´ bien, c’est d’occuper et d’aneantir un nombre d’Allemands considerable et ˆ croissant avec le temps. Si cette condition continue d’etre remplie pendant ´ enements ´ ´ ´ ˆ encore 3 ou 4 mois, les ev decisifs se derouleront sur le the´ atre occidental. ` sera malheureusement achete´ par des pertes irreparables ´ Le succes ; ´ parmi les tristes nouvelles que j’ai apprises recemment, une de celles qui m’a fait le plus de peine est la mort de Gateaux.54 Les conditions dans ´ ne laissent malheureusement qu’un bien lesquelles elle nous est annoncee ´ ´ faible espoir d’une erreur. Je veux neanmoins esperer que sur les dizaines ´ eves ` ´ comme perdus, il s’en trouvera au d’el de l’Ecole Normale regardes moins un ou deux qui reviendront a` la fin de la guerre. 51
See footnote 44.
52
Guglielmo Ferrero (1871–1942) was historian, sociologist, journalist and writer. He studied at the universities of Pise, Bologna and Turin. In 1930 he escaped from the Fascism and went to Switzerland – he was professor at the University of Geneva. He was a specialist of ancient history; he published a history of the ancient Rome in five volumes by using an economist key of interpretation.
53 54
See footnote 47.
See footnote 36. It is not clear how Gateaux’s death was communicated to Borel (see Laurent Mazliak: Les fantˆomes de l’Ecole Normale in [22]).
48
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ e´ eprouv ´ ´ les hommes de mon age ˆ ne Jusqu’ici, notre famille n’a pas et ee; ´ 55 sont toujours pas appeles. ´ Veuillez presenter mes hommages a` Madame Volterra et croire toujours ´ a` ma bien affectueuse amitie. Emile Borel
Volterra to Borel n.p., n.d. [December 1914] (draft) Mon cher ami, J’ai appris avec une grande peine la triste nouvelle que vous m’avez ` reunion ´ ´ de la mort de Gateaux.56 Je l’ai communique´ a` la derniere donnee ´ ´ ` du Seminaire mathematique et tous les collegues ont accueilli cette nou57 ´ egramme. ´ velle avec le plus vif regret. Vous avez sans doute rec¸u notre tel Gateaux avait beaucoup de talent et je suis sur ˆ qu’il avait un grand avenir. Il ˆ ´ ´ ` [canceled : peut-etre lente, mais] toudeveloppait ses idees d’une maniere ´ passee ´ il avait beaucoup travaille´ et je ne doutais pas jours sure. L’annee ˆ ` etaient ´ ˆ 58 Combien de jeunes que tous les fondements pour sa these prets. ´ e´ les victimes de cette guerre! C’est horrible a` y penser. existences ont et ` connu comme journaliste. Il a et ´ e´ le Directeur du M. Moneta59 est tres ´ Nobel (prix pour Secolo et il a beaucoup travaille´ pour la paix. Il est Laureat ´ e´ couronne´ il y a quelques annees. ´ la paix) car il a et Les nouvelles de la guerre montrent que les conditions de l’Allemagne et de l’Autriche vont toujours pire. Ce n’est pas possible de douter sur le 55
In principle, the men who were aged more than 37 and belonged to the so-called Territorial army were not supposed to be sent to the Front. However, due to the enormous losses of the beginning of the war, older men were regularly called to the Army. A celebrated example is the 41 years old writer Charles P´eguy who died in September 1914 during the battle of the Marne. Borel, who was in the Classe 1891 (meaning that he was born in 1871), belonged to the reserve of the territorial army. He enlisted some months later (see below).
56
See footnote 54.
57
Volterra has sent a telegram to the Ecole Normale on behalf of Rome mathematical seminar to express his deep sorrow about Gateaux’s death. It reads: “Mathematical seminar Rome expresses its deep sorrow received news his former member Gateaux and all its great sympathy to Ecole Normale. Director Volterra”.
58
Luckily for his memory, Gateaux had left many papers in his mother’s house in Vitry-leFranc¸ois. Among them, several articles on functional calculus, potential theory and infinite dimensional integration. The amazing destiny of these papers recovered by Hadamard during the war is narrated in Laurent Mazliak: Les fantˆomes de l’Ecole Normale in [22]. They played an important rˆole in L´evy’s career.
59
See footnote 44.
Mathematicians at war
49
` de la Triple Entente. Je suis impatient que notre intervention contre succes les deux empereurs allemands ait lieu. ´ eral ´ Je lis le livre du Gen Percin60 que vous avez publie´ dans votre col` interessant. ´ ` nouveau lection et je le trouve tres Pour moi il est aussi tres ` fois que je m’interesse ´ car c’est la premiere a` des questions militaires. Mais dans ce moment il le faut bien.
Volterra to Picard n.p., n.d. [January 1915] (draft) ` cher M. et cher A. Tres ´ 1915 commence dans les circonstances les plus tragiques,61 L’annee ´ ` de la triple entente continuent et que mais tout fait prevoir que les succes ´ l’Allemagne et l’Autriche devront plier sous les efforts reunis des nations ´ ´ civilisees. Il n’y a pas de doute que le resultat de leur commune agression sera fatale pour les empires allemands et que le principe de nationalite´ sortira de la conflagration actuelle. Je fais aussi des vœux chaleureux pour que ˆ de la neutralite´ et pour une intervention contre mon pays sorte au plus tot l’Autriche et l’Allemagne. Aux vœux que de tout mon cœur je vous envoie ´ j’ajoute cette fois les vœux les plus sinceres ` chaque annee pour la victoire ´ definitive de la France. ´ apres ` les efforts communes et apres ` que Je suis sur ˆ que la paix gagnee ´ ` ´ le danger du militarisme allemand sera evanoui amenera une periode nou´ ` les nouvelles que j’ai velle de l’histoire de la civilisation europeenne. Apres ` que vous pouvez etre ˆ rec¸u de votre part et aussi d’autres sources j’espere maintenant plus tranquil[!] a` propos de vos enfants. J’ai su que l’un de vos ´ e´ blesses, ´ mais j’espere ` que leurs blessures ne sont fils et M. Dunoyer ont et pas dangereuses. Veuillez accepter pour eux et pour les autres membres de votre famille tous mes vœux.
60 The book Le Combat (The Fight, available in digitized form on Gallica) was written by General Alexandre Percin (1846–1928) in 1914 and published by Borel in the collection Nouvelle collection scientifique he supervised for the publisher F. Alcan. As General Percin asserts in the introduction, the book is intended to provide non specialists of military technique (“even the mothers and the children”, writes the author!) with some basic insights on how military operations are conducted. Borel had probably considered the subject appropriate for his collection at this moment. 61
In January 1915, the Italian newspaper Corriere della Sera carried news of “awful battles” on the East Front (January 1st), the sinking of the British battleship “Formidable” (January 2nd), and eight English villages destroyed by German bombing (January 21).
50
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
La vie a` Paris a repris maintenant. Je l’ai lu dans les journaux et tous ` que vous serez main´ 62 J’espere ceux qui en reviennent me l’ont confirme. ´ ´ tenant reuni avec votre famille. Veuillez bien presenter de ma part et de part de M.me Volterra tous nos meilleurs vœux a` M.me Picard et a` toute votre famille.
Picard to Volterra Paris, 25 January 1915 Mon cher ami, ˆ Un coup cruel vient de me frapper. Mon fils aˆıne´ vient d’etre tue´ d’une balle au front dans un combat autour de Soissons.63 Il disparait a` trente ans, alors que, Inspecteur des Finances, il avait un bel avenir devant lui. Nous ´ ´ sommes aneantis par cette perte irreparable. Mon second fils est aussi en pleine bataille, et nous tremblons constamment pour lui. Mon gendre est lui ` expose, ´ etant ´ ´ aussi tres officier observateur en aeroplane. Puissent tant de ˆ sacrifices n’etre pas inutiles, et la barbarie Allemande, qui trouble le repos ˆ ´ ´ du monde, etre un jour pas trop eloign e´ reduite a` merci. Malgre´ ses tristesses, il faut songer aux ruines de la guerre, et j’ai a` vous ´ entretenir d’une question qui nous interesse beaucoup a` l’Institut. Il s’est ` ´ forme´ a` l’Institut un comite´ pour la reconstitution de la bibliotheque detruite 64 ´ Nous de Louvain, comite´ qui ne se limite pas d’ailleurs aux academiciens. ´ ˆ dans les divers pays (en dehors desirerions qu’uncomite´ analogue se format
62
Volterra’s words contrast remarkably with the picture of the situation presented by the Italian newspaper Corriere della Sera at this very moment. The newspaper published awful news about the war in France during all January 1915!
63
The Caporal (corporal) Charles Louis Edouard Picard, born in Paris in 1884, was killed in Crouy on January 8th, 1915. Between 8 and 12 January, a violent fight took above the small village of Crouy to defend the town of Soissons. See http://www.chtimiste.com/batailles1418/combats/ Crouy.htm
64
In August 1914 the Library of the University of Louvain was destroyed by the German Army. It had been founded in the 17th Century and contained about 300.000 volumes when burnt. As Theodore Wesley Koch writes in his book devoted to the University Library of Louvain: “A committee was formed under the leadership of Viscount Bryce [James Bryce (1838–1922) British politician, diplomat, and historian] as President of the British Academy, to cooperate with the Institut de France in the formation of an International Committee which should have for its aim the restoration of the University of Louvain and its library.” (The University of Louvain and its Library, Norwood, The Plimpton Press, 1919; the quotation is on p. 47)
Mathematicians at war
51
bien entendu de nos ennemis). Nous comptons tout d’abord envoyer une ´ et correspondants, esperant ´ circulaire dans chaque pays a` nos associes qu’ils voudront bien former un groupement qui serait le noyau du comite´ ´ ` qu’un de nos correnational de ce pays. Il serait necessaire pour le succes ´ ˆ ˆ spondants dans chaque pays voulut etre l’ame ˆ bien, au moins au debut, de ce groupement. Je viens donc vous demander votre avis a` ce sujet, ` que vous voudrez bien vous interesser ´ ` et j’espere particulierement a` cette œuvre, en centralisant les premiers efforts pour former un Comite´ Italien. Nous ne lancerons notre circulaire que quand nous serons surs ˆ de trouver dans chaque pays un de nos correspondants qui veuille bien prendre une part active a` nos projets. On se proposera de reconstituer, autant qu’il est ` possible, la bibliotheque de l’Universite´ de Louvain, soit par des dons des livres, soit par des dons en argent. Me permettant a` l’avance, cher ami, de compter sur votre concours actif ´ a` notre œuvre, j’ajoute que les principaux membres des divers comites nationaux formeront un Grand Comite´ International. ´ Croyez moi votre bien affectueusement devou e´ Emile Picard
Volterra to Picard Roma, n.d [January/February 1915] (draft) Mon cher Ami C’est avec la plus vive peine que j’ai appris le terrible malheur qui vous ´ Votre fils est mort en heros ´ a frappe. en combattant contre les barbares ˆ invaseurs [!] de la patrie. Tous ceux qui ont le culte des ames bonnes et ´ ıques partagent votre deuil. Veuillez accepter toutes mes condoleances ´ hero¨ ´ et veuillez aussi presenter l’expression de mes sentiments de la plus proˆ fonde sympathie a` Madame Picard et a` toute votre Famille. En meme temps ` veuillez accepter les vœux les plus sinceres [?] pour ceux de votre famille qui ´ se battent. Les sentiments d’execration contre les allemands et le sentiment ´ ´ de la necessit e´ d’ecraser leur nuisible puissance se font de jour en jour plus ´ forts chez nous. Et la necessit e´ de notre intervention devient toujours plus populaire. ` que la vœu que j’ai fait de l’intervention de l’Italie contre l’Autriche J’espere ´ ´ et l’Allemagne depuis le premier jour que la guerre a eclat e´ se realisera ˆ bientot. Vous pouvez compter sur moi a` propos du comite´ pour la reconstitution ` ` de la bibliotheque de Louvain. Je suis completement a` votre disposition pour ´ tous les [renseignements (?)] que vous desirez et pour l’organisation en ´ Italie. Je ne doute pas que cela reussisse chez nous.
52
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
` En Italie on a souvent encore que lorsque la bibliotheque de Turin est ´ par un accident il y a a` peu pres ` dix ans nous avons rec¸u des offres brul ˆ ee ´ e´ et des cadeaux qui ont servi a` reconstituer une partie des fonds qui avait et perdus.65
Picard to Volterra Paris, 16 February 1915 Cher ami, ´ Je vous ai ecrit, il y a un peu plus de trois semaines, pour vous demander ´ si vous voudriez bien vous interesser a` une oeuvre que l’Institut entreprend, ` et qui est relative a` la bibliotheque de Louvain. Les Correspondants de l’Institut vont d’ici quelque temps recevoir une lettre a` cet effet. Il s’agit de solliciter, soit des dons en argent, soit des livres ` ´ pour reconstituer la bibliotheque aneantie. Bien entendu, aucun envoi ne ´ e´ evacu ´ sera fait avant que Louvain n’ait et e´ par les Allemands. ˆ ´ e´ egar ´ ´ j’avais la douleur de Dans cette meme lettre qui a sans doute et ee, ´ tue´ dans la bataille de Soissons le vous annoncer la mort de mon fils aˆıne, 8 Janvier, a` l’age de trente ans. C’est un coup terrible dont nous ne nous ` releverons jamais, ma femme et moi. ´ ´ Croyez, cher ami, a` mes sentiments affectueusement devou es, Emile Picard
Volterra to Picard n.p., n.d [March 1915] (draft) Mon cher Ami, Ne croyez pas que j’aie oublie´ le comite´ pour l’Universite´ de Louvain dont ´ vous m’avez ecrit il y a quelque temps. J’ai parle´ avec plusieurs amis de ´ Rome et d’autres villes, et j’ai justement obtenu que le Conseil Superieur de ´ l’Instruction Publique fut reuni, pour m’entretenir avec quelques membres de ce conseil.
65
In the night between 25 and 26 January 1904, five rooms of the National Library of Turin were destroyed by a fire. Among them the rooms containing manuscripts and incunabula. The Corriere della Sera of 28 January carried the news that the fire was not yet extinguished and more than 4000 manuscript were destroyed as well as all the volumes published in Europe between 1625 and 1750. The cause of the fire was unknown.
Mathematicians at war
53
M. le Recteur de l’Universite´ de Rome, Monsieur Somigliana de Turin, M. ´ De Marchi de Padoue qui etaient ici il y a peu de jours doivent m’envoyer ´ l’adhesion de M. Boselli, Ciani, D’Ovidio, Tamassia , Veronese.66 J’attends ´ des amis. aussi de la part de mon ami Marcolongo67 des adhesions Je crois que ces amis seront suffisants pour constituer un premier noyau, ˆ ´ comme je pense que vous-meme desirez. Si vous croyez vous n’avez qu’a` m’envoyer le [here the text is discontinuous. Maybe a page is missing] Vous ne pouvez pas vous imaginer quels moments nous passons et ´ nous trouvons pour mener a` bout la plus petite chose. quelles difficultes ´ ´ Toutes nos forces sont a` ce moment consommees pour la realisation de ` nos aspirations c’est-a-dire pour marcher en guerre contre l’Autriche et ´ e´ la seule solution [here the text is discontinuous. l’Allemagne. La guerre a et Next page is missing]
66
Carlo Somigliana (1860–1955) studied at the Universities of Pavia and Pisa, and graduated in mathematics in 1881. In 1892 he became professor of mathematical physics at the University of Pavia and in 1903 moved to the University of Turin. He followed the research of Betti and Beltrami, and his main contributions concern the theory of elasticity and the propagation of seismic waves. Luigi De Marchi (1857–1936) graduated in mathematics and physics at the University of Pavia and in 1902 was appointed professor of physical geography at the University of Padua. He researched on glacial age and propagation of seismic waves. He was appointed Senator in 1934. Paolo Boselli (1838–1932) was an Italian politician. He was minister of Public Education, minister of Agriculture and minister of Finance. He also was Prime Minister during the War, from June 1916 to October 1917; he resigned as minister just after the defeat of Caporetto when Orlando took his place. Edgardo Ciani (1864–1942) graduated in mathematics from the University of Pisa in 1886 and was assistant professor at the same university for about ten years. In 1906 he became professor of projective geometry at the University of Genoa and in 1925 he moved to the University of Florence. Enrico D’Ovidio (1843–1933) studied at the University of Neaples and in 1872 became professor of algebra and analytical geometry at the University of Turin. He gave some interesting contributions to geometry and was the master of Corrado Segre, who was the founder of the Italian school of algebraic geometry. Nino Tamassia (1860–1931) was a jurist and professor of history of law at the University of Padua. He published many books concerning history of law during the Roman-Greek period and the High Middle Ages. He was appointed Senator in 1919. Giuseppe Veronese (1854–1917) graduated from the University of Rome in 1877 and in 1881 was appointed professor of analytical geometry at the University of Padua. He founded the projective geometry of the iperspaces from the proper geometrical point of view and the so-called non-archimedean geometry.
67
The mathematician Roberto Marcolongo (1862–1943) obtained in 1895 a position of professor of Rational mechanics in Messina and then transfered to Naples where he remained until his retirement. He was a renowned teacher and published a large number of textbooks. He had also interests in history of science and was an active member of the commission for the publication of Leonardo da Vinci’s works.
54
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Picard to Volterra Paris, 17 March 1915 Cher ami, ´ Excusez moi de ne pas avoir repondu encore a` vos deux lettres que j’ai ´ egramme. ´ bien rec¸ues et a` votre tel J’ai, depuis trois semaines, de grandes ´ inquietudes au sujet de mon second fils qui est engage´ dans les batailles de ˆ Champagne et a failli etre tue´ il y a peu de jours.68 Je vous remercie vivement de bien vouloir vous occuper de la reconsti` tution de la bibliotheque de Louvain. Pourriez vous m’envoyer une liste des savants Italiens (la science (sciences de la nature, histoire, philosophie, etc.) ´ ´ eral), ´ etant prise au sens le plus gen que nous inviterions a` faire partie du ´ et a` qui l’Institut enverrait une lettre indiquant le projet dans ses Comite, ´ pour le moment ou` la grandes lignes. Nous aurions ainsi des cadres traces ´ realisation deviendra possible. Le comite´ ainsi constitue´ avec des savants de divers pays serait le Comite´ International; dans chaque pays se formeraient ´ nationaux sous les auspices des membres du Comite´ ensuite des comites international appartenant a` ce pays, et ou` pourraient figurer des personnes ˆ pouvant par leur situation etre utiles a` l’œuvre. J’ai bon espoir que tout cela pourra se faire assez facilement. ´ ´ Ma femme s’excuse de ne pas avoir encore repondu aux condoleances ´ ` souffrante, vivant dans l’angoisse emues de Madame Volterra; elle est tres ´ Veuillez, en attendant, pour notre second fils et pleurant son fils aˆıne. remercier M.me Volterra de notre part. ` Je considere, pour ma part, que la guerre est a` peine a` son milieu. La ´ defaite de l’Allemagne est certaine; mais le temps est indispensable pour venir a` bout, sans sacrifier trop de milliers d’hommes, de cette organisation ´ ´ depuis plus de quarante ans. La France, en somme, si savamment prepar ee ˆ aujourd’hui, mais vous pouvez etre ˆ est seulement prete assure´ qu’elle est ˆ Armements, munitions, tout est a` souhait. bien prete. Croyez, cher ami, a` mes sentiments de vieille et vive affection, Emile Picard
68
In February and March 1915, several important offensives were organized on the Champagne front to try to break the German lines. The effect (apart from heavy losses) was negligible.
Mathematicians at war
55
Picard to Volterra Paris69 , 26 May 1915 Mon cher ami, ´ ´ ´ enement ` Votre lettre recente me faisait presager le grand ev qui vient de se produire. Nous avons vu en France avec une joie infinie l’Italie entrer dans la grande lutte de la Civilisation contre la Barbarie.70 L’ennemi est ´ a` bien touche, ´ et on peut penser que la resistance ´ encore fort, mais il est dej ´ qu’il deploie ´ ´ acharnee s’affaiblira tout a` coup. Ici nous considerons que la ´ guerre sera encore longue, car il est necessaire d’aller jusqu’au bout dans ´ cette lutte gigantesque depassant de beaucoup les plus grandes guerres de ´ e´ accumulees ´ et assez de sang aura et ´ e´ l’histoire. Assez de ruines auront et verse´ pour que l’Europe jouisse longtemps de la paix. ´ avec la sigJe vous envoie, comme indication, la lettre qui sera envoyee, ´ Italiennes nature d’un des membres du Comite´ de Paris, aux personnalites dont je vous prie de m’envoyer les noms et dont vous serez surs de la sympathie pour notre œuvre de Louvain; il faudrait environ seize noms pour l’Italie, mais bien entendu ce n’est la` qu’une indication vague. Le Comite´ ˆ international ne peut pas etre trop nombreux. Je crois que vous avez duˆ avoir la visite du Ministre Belge M. Van den Heuvel, qui vous aura donne´ 71 ´ quelques details. Nous vivons toujours bien tristement. Mon second fils a actuellement un conge´ de convalescence de deux mois, pour achever de se remettre d’une ´ de terribles combats en crise nerveuse assez grave que lui ont causee Champagne au mois de Mars. Mon gendre M. Dunoyer lance des bombes du haut des avions.72 C’est un exercice dangereux, et nous vivons toujours ´ dans l’inquietude a` son sujet. ´ ´ En souhaitant a` nos armees alliees de belles victoires, je vous prie de ` affectueusement devou ´ ´ et vous croire, cher ami, a` mes sentiments tres es, demande de bien vouloir transmettre a` Madame Volterra mes respectueux souvenirs. ˆ Bien cordialement votre Emile Picard 69
Letterhead : Institut de France.
70
Italy eventually declared war to Austria on 23 May 1915. The war with Germany took place only more than a year later, on 27 August 1916, and this strange situation created some difficulties with the Entente (see footnote 119).
71
Jules van den Heuvel (1854–1926) was a Belgian Delegate to the Holy See. He was a member of the Belgian delegation to the peace conference in 1919. In 1918 Van den Heuvel obtained that German government gave back books, manuscripts and other objects destroyed in the 1914 fire to the Library of Louvain. See www.ars-moriendi.be/VAN DEN HEUVELFR.HTM
72
See footnote 68.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Volterra to Picard Roma, n.d. [June 1915] (draft) Mon cher Ami, Je vous suis fort reconnaissant de votre aimable lettre. Ce que vous ´ m’avez ecrit par rapport a` ma Patrie m’a bien touche´ ! Je suis heureux que l’abominable liaison avec les empires allemands soit finie et que l’Italie ˆ e´ de sa soeur latine. C’etait ´ marche en guerre, a` cot mon vœu depuis le ´ commencement de la conflagration europeenne, vous le savez bien. Nous ´ ´ mais avons passe´ des mois bien tristes pendant la periode de la neutralite, je n’ai jamais doute´ de ce qui arrivait car j’ai toujours eu la persuasion ` [?] pour sauvegarder notre honneur: qu’il n’y avait qu’une seule maniere il fallait marcher contre les ennemis de la civilisation. Depuis notre intervention l’enthousiasme a envahi toutes les classes sociales chez nous, mais il ne faut pas croire que notre peuple ait l’illusion que la guerre soit facile.73 ´ Nous savons que nous aurons a` soutenir des cruelles epreuves, mais nous sommes surs ˆ du triomphe final de la quadruple entente. Nos efforts serviront pour la cause de la justice et de la liberte´ et nous sommes heureux de faire ´ La France nous donne un noble exemple tous les sacrifices pour cet ideal. depuis les 10 mois qu’elle se bat si vaillamment. ` que la sante´ de votre fils ne vous donne plus des preoccupations. ´ J’espere ´ Je sais que la vie dans les tranchees est terrible et donne des crises nerveuses, mais une vie paisibles de quelques semaines le remettra. Je fais tous mes vœux pour lui et pour M. Dunoyer que se bat si ´ courageusement. Ci inclus vous trouverez la Note des noms pour le Comite. Je suis sur ˆ de leur sympathie pour l’œuvre de Louvain. Je n’ai pas vu ˆ dans les derniers temps M. le Ministre de la Belgique. Je tacherai de le voir.
73
This sentence seems rather exaggerated. Historians usually point out the neutralist attitude of Italian people towards the War, in contrast with the interventionism of intellectuals; see for instance [51, 19].
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Hadamard to Volterra Paris, 1 July 1915 Universite´ de Paris ´ Ecole Normale Superieure Laboratoire de Physique 45, rue d’Ulm Paris (5e Arrt ) ´ ephone: ´ tel Gobelin 06-45 ` Mon cher collegue et ami, ´ Il y a longtemps que je voulais vous ecrire, – depuis que j’ai su, par ´ es, ` 74 par M. Richet75 et par d’autres, combien vous avez donne´ de votre Per peine et de votre flamme au grand mouvement qui anime en ce moment ´ l’Italie. Il faudrait douter de l’admirable elan de sympathie que notre jeunesse ˆ e, ´ affirme par le sacrifice de sa vie, si nous n’y trouvions pas, de notre cot ´ ´ dans l’occasion de rappeler et de resserrer les precieuses relations nouees ´ un temps ou` nous n’en etions qu’a` soupc¸onner la barbarie boche. Quant a` moi, je me rends utile comme je peux – ce n’est pas grand chose – en aidant a` un certain nombre de recherches techniques. L’aˆıne´ ` de mes fils est engage´ depuis les premieres semaines de la guerre. Il vient de prendre part, comme sous lieutenant d’artillerie, aux plus rudes affaires ´ de s’engager. d’Ypres76 et de Carency.77 Le second vient egalement Je pense que vous serez heureux d’apprendre comment s’est comporte´ ´ ˆ de 1908, M. Debre. ´ 78 Il a – egalement comme officier d’artillerie – votre hote ´ e´ pris part a` toute la grande retraite et a` la bataille de la Marne; puis il a et blesse´ aux premiers jours de la bataille de l’Aisne, dans les circonstances ´ les plus glorieuses, puisqu’elles lui ont valu la croix de la Legion d’Honneur 74
See ♥ 7.
75
See footnote 32.
76
Strategically located along the roads leading to the Channel ports in Belgian Flandres, the Belgian Ypres had been the scene of important battles during the First World War. A first battle occurred in Autumn 1914 and a second battle – to which this letter refers to – in April 1915. More in detail, the first battle of Ypres commenced on October 14 when the Fourth and the Sixth German armies were sent into Ypres. This offensive was halted with arrivals of French reinforcements; another German offensive followed but ultimately without success. The second battle of Ypres followed the only major attack launched by the German forces on the Western Front in 1915. It is concluded in failure for the German Army in May. As a consequence, German Army did not attack Ypres any more, choosing to demolish it through bombardments.
77
German Army destroyed the village of Carency during the first battle of Artois (Autumn 1914). On May 1915 a French offensive began (second battle of Artois). They attacked Carency, Neuville Saint-Vaast et Le Labyrinthe, already conquered by the German Army.
78 Jacques Debr´e (1885–1969) studied at the Ecole Polytechnique and became an electrical engineer. He was one of Hadamard’s nephews.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ Il s’agissait d’une reconnaissance ou` il a et la citation a` l’ordre de l’armee. obtenu des renseignements importants. Pendant la retraite, il a eu a` passer des jours et des nuits a` cheval sans dormir plus de quelques minutes de ´ ˆ d’une formation d’artillerie suite. A peine retabli, il vient de repartir a` la tete lourde. ´ Presentez tous mes respects et les meilleurs souvenirs de ma femme a` ˆ nous recrire ´ Madame Volterra – et puissions nous bientot pour nous annon´ ´ cer une belle defaite de ces miserables! A vous cordialement J. Hadamard
Volterra to Hadamard n.p., n.d [July 1915] (draft) Monsieur et cher Ami ` reconnaissant de votre bonne lettre qui m’a fait le plus Je vous suis tres ´ grand plaisir. Depuis le commencement de la guerre europeenne j’ai tou´ e´ l’intervention de l’Italie a` cot ˆ e´ de la France et de ses allies ´ et j’ai jours desir ´ e´ heureux lorsque la quadruple entente a et ´ e´ definitivement ´ ´ et constituee. ` de ces J’ai consacre´ tous mes efforts a` ce but. Je ne doute pas du succes ´ alliees ´ et de l’ecrasement ´ ´ armees definitif de l’Autriche et de l’Allemagne. ´ de nationalite´ de justice et Nous combattons pour les principes sacres ` ce moment a` continuer, apres ` les combats de civilisation. Il faut penser des ´ la guerre savante et economique contre les puissances allemandes. Depuis ´ quelque temps je ne travaille plus dans les mathematiques. Les questions ´ ´ e´ politiques et militaires ont pris le dessus et toutes nos energies y ont et ´ ´ consacrees. Maintenant je fais partie de l’Institut militaire d’Aeronautique ´ qui s’occupe des questions theoriques et pratiques de l’aviation. J’ai bien regrette´ les pertes douloureuses. Vous avez sans doute connu ´ a` Rome. Il avait beaucoup de talent Gateaux79 qui avait passe´ une annee et je serais heureux si l’on pouvait trouver parmi ses papiers ses derniers ´ ´ et. ˆ J’ai rec¸u quelques lettres de M. resultats qui avaient beaucoup d’inter ´ ˆ aux tranchees. ´ volontaire et aussitot Mais depuis quelque Soula80 qui etait temps je ne rec¸ois plus de ses nouvelles. Pouvez-vous m’en donner? ` de recevoir de bonnes nouvelles de lui. J’espere
79
On Gateaux, see footnote 16.
80
On Soula, see footnote 46.
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` ´ es ` 81 et j’ai vu avec beaucoup de plaisir que J’ai rec¸u la these de M. Per ´ e´ un de ses examinateurs. vous avez et Les nouvelles que vous me donnez de M.82 m’ont fait beaucoup de plaisir. ´ Vous m’obligerez beaucoup si vous voudrez bien lui presenter toutes mes ´ felicitations et l’expression de toute mon admiration. ´ eves ` Tous mes el sont militaires. La plupart dans l’artillerie et dans le ´ ´ ere ` les ingenieurs ´ ´ genie, ou` l’on pref et les mathematiciens. Je fais les meilleurs vœux pour votre famille. Pensez [the text is interrupted here]
Hadamard to Volterra Paris, n.d. [August 1915] Cher ami, ´ plaisir, comme vous le pensez. Votre mot si cordial m’a fait un bien reel ` douce sensation, et bien necessaire ´ C’est une tres en ce moment, que de ˆ ´ ´ qui ont et ´ e´ precieuses ´ sentir meme a` distance, les precieuses amities de tout temps, mais qui le sont plus encore et qu’on sait plus vives et plus ´ etroites au milieu de la crise actuelle. ´ Il est assez naturel que nos destinees se ressemblent en ce moment. Je suis, comme vous, assez fortement occupe´ et de questions voisines de ´ e´ voue. ´ Et, comme consequence ´ celles auxquelles vous vous et aussi, je fais ` au College de France – je ne parle plus, bien entendu, de l’Ecole Polytech´ eves ` ˆ nique dont tous les el se battent et qui est convertie en hopital – de 83 ` rares el ´ eves. ` rares cours pour de tres
81 P´er`es defended his Thesis Sur les fonctions permutables de premi`ere esp`ece de M. Vito Volterra in 1914; it has been published in 1915 (Paris, Gauthier-Villars). 82 83
sic. Probably Volterra meant Debr´e, quoted in Hadamard’s letter.
The lectures at the Ecole Polytechnique immediately stopped at the beginning of the war (more precisely, they never opened for the academic year 1914–15). On Hadamard and the Ecole Polytechnique during the war, see J.-L. Chabert et Ch. Gilain: Jacques Hadamard, un itin´eraire a` travers la premi`ere guerre mondiale in [22]. At the Coll`ege de France, a considerably limited activity was maintained. David Aubin communicated several letters from George D. Birkhoff’s students to us that he found at Harvard University Archives. A letter written by Raymond W. Brink on 11 November 1916 describes his disappointment about the poor mathematical life in Paris, and the total lack of organization. Brink wrote: “it is impossible to say how badly shattered the system at the Sorbonne is, by the war”.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Ma femme me charge de ses meilleurs souvenirs pour Madame Volterra et pense qu’elle jouit bien du bonheur d’avoir des enfants encore si jeunes en ce temps.84 Jusqu’ici heureusement, notre fils aˆıne´ a traverse´ la guerre sans dommage, bien qu’il ait assiste´ a` quelques unes des actions les plus vives. Je vous remercie bien vivement de vos bons souhaits et vous prie de ˆ recevoir tous les notres et, avec tous mes respects pour Madame Volterra, ´ mes meilleures amities J. Hadamard
Volterra to Picard Roma, 29 July 1915 Monsieur et cher Ami, ´ ´ a` longtemps une lettre ou` etait ´ Je vous ai ecrit il y a dej incluse la liste des noms que j’avais recueillis pour constituer en Italie la Commission pour la ` Bibliotheque de Louvain. L’avez-vous rec¸ue? N’ayant rec¸u aucune communication a` ce sujet je crains que vous n’avez ´ e´ perdue, ce pas rec¸u ma lettre. Veuillez bien me faire savoir si ma lettre a et qui n’est pas rare a` ce moment. ´ Je desire aussi beaucoup savoir des nouvelles de votre Famille. Je fais les meilleurs vœux pour votre fils et vos gendres qui combattent. Nous sommes en Italie enthousiastes de la guerre quoique nous savons ` final de la quadruple qu’elle sera longue, mais nous sommes surs ˆ du succes ´ entente. Je fais partie maintenant de l’Institut militaire d’aeronautique et cela m’occupe beaucoup.85 ` de la vaillante armee ´ Veuillez accepter les meilleurs vœux pour le succes ´ Franc¸aise. Veuillez bien presenter ´ alliee mes hommages a` Madame Picard ´ et a` votre Famille et veuillez agreer, mon cher Ami, l’expression de toute ´ mon affection et de tout mon devouement. Vito Volterra
84
This sentence shows an amazing contrast between Hadamard’s realism and Volterra’s obstinate interventionism. See ♦ 5 .
85
Volterra joined the Army in the Aeronautics as a volunteer.
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Picard to Volterra Hauteville, 5 August 1915 ˆ du Chateau ˆ Grand hotel Hauteville86 Ain Cher ami, Une triste fatalite´ s’est abattue sur ma famille. Depuis deux mois ma ` fille est extremement ˆ ´ ` grave qui laisse derniere malade d’une anemie tres peu d’espoir. Nous l’avons conduite, il y a quelques jours, dans l’Ain sur un ´ e, ´ ou` elle trouvera un bon air et des soins medicaux ´ ´ plateau elev speciaux. ˆ L’hotel ou` je viens de m’installer avec ma femme et ma seconde fille est a` ` ´ un kilometre de l’etablissement ou` notre malade est en traitement. Quand je verrai la tournure que prend la maladie, je retournerai a` Paris, ou` j’ai ` beaucoup a` faire en ce moment; ce sera, je l’espere, pour la fin du mois. ´ e´ malade pendant deux mois; il est maintenant retourne´ Mon fils a et ´ edemment, ´ ´ au front, mais est un peu moins expose´ que prec etant dans ´ une section de reperage des canons ennemis, ce qui est moins dangereux ´ que l’infanterie. Mon gendre Dunoyer fait toujours de grandes expeditions ´ ` de Nancy.87 aeriennes, et se trouve actuellement pres J’ai bien rec¸u votre lettre, et je dois m’excuser de ne pas vous avoir ´ ´ repondu. La faute en est a` mes preoccupations personnelles. M. Imbart de la Tour pense que, pour le Comite´ international, votre liste comprend un trop grand nombre de noms.88 Ne l’ayant pas ici, il m’est difficile de vous en ´ ` mon retour a` Paris, en parler aujourd’hui, mais je vous ecrirai a` ce sujet des vous proposant quelques simplifications.
86
The village of Hauteville (today connected with another village called Lompnes) is situated in the Bugey on a plateau linking the Alps and the Jura, at an altitude of ca. 1000 m over the sea. It was one of the first places in France to possess a sanatorium (since 1897) where weak and convalescent people where sent to follow a treatment of “fresh air”. An interesting iconography can be consulted on the web http://www.notrefamille.com/1110-hauteville-lompnes/cartes-postales-190064355-ville-village.html
87
First appearance in the correspondence of the important problem of sound ranging of guns. The subject recurrently appears in the exchanges until 1918. On these matters, see David Aubin: Le coup d’oeil du scarab´ee in [22] and Martina Schiavon: The Special detection in France and in Italy during the First World War, to appear. See also footnote 101.
88
Pierre Imbart de la Tour (1860–1925) was a French historian. He was professor at the University of Besanc¸on and Bordeaux. He was elected at the Acad´emie des sciences morales et politiques in 1909. He published important works on the history of Church in the Middle Ages, and on the origin ´ of the protestant Reform in France. Imbart de la Tour and Etienne Lamy (1845–1919) were at the head of the French Committee for the restoration of the University Library of Louvain; Imbart de la Tour was also the President of the Comit´e International founded in 1916.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ ´ J’etais ´ La guerre suit le cours que beaucoup avaient presum e. de ceux` cette guerre inouie ne peut etre ˆ ´ et un nouvel hiver est la; finie cette annee, ´ necessaire pour amener l’usure de nos ennemis communs. Voila` l’Angleterre ´ Italienne s’est dej ´ a` dont les armements avancent, et votre vaillante armee ´ et a montree ´ sa superiorit ´ ´ Le recul des Russes brillamment signalee e. ´ que le jour n’est pour les Allemands qu’un triomphe platonique.89 Esperons ´ seront tous ligues ´ contre l’effroyable barapproche ou` les peuples civilises ´ ´ de dominer le monde, et de faire ses esclaves du barie qui s’etait proposee ´ reste de l’humanite. ` en 1916 de nos efforts comTous mes vœux, cher ami, pour le succes ´ ´ muns qui doivent liberer le monde. Veuillez presenter nos respectueux sou` venirs a` Madame Volterra et croire a` mes sentiments de vieille et sincere affection, Emile Picard
Picard to Volterra Paris, 30 August 1915 Cher ami, ´ ´ dans Je suis rentre´ a` Paris depuis quelques jours, ma femme etant restee ` fille, dont l’etat ´ l’Ain avec ma derniere nous inspire toujours les plus vives 90 ´ . Je vis en ce moment dans une angoisse continuelle, tant de inquietudes ˆ e´ que relativement a` mon gendre qui fait de dangereuses expeditions ´ ce cot ´ ´ aeronautiques, l’aviation prenant chaque jour un plus grand developpement. ˆ ˆ e´ dans une section Mon fils est moins expose´ maintenant, ayant pu etre enrol ´ de reperage (par le son) des canons ennemis. ´ pour ´ Je vous ai ecrit de Hauteville91 que la liste que vous m’avez envoyee le Comite´ International relatif a` Louvain avait paru un peu longue. Sur votre liste, M. Imbart de la Tour a marque´ quelques noms d’une croix, comme ´ ´ etant ceux qui lui semblent a` conserver de fac¸on a` etablir une proportion ´ ´ mais il ne veut rien convenable entre les differentes villes et Universites, faire, comme nous tous, sans votre assentiment. Je vous envoie aussi une
89
During the spring 1915, the Russian armies were defeated several times in the Carpathians and in Galicia where the front collapsed in June. The Russian retreat resulted in terrible consequences for the civilians living near the battlefield (see footnote 96 below and also ♥ 8).
90
Madeleine, Emile Picard’s youngest child died on 21 October 1915 in Hauteville. She was 22 years old.
91
See footnote 86.
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seconde liste, en vous priant de marquer d’une croix sur cette liste ceux qui ´ ´ pour le Comite´ International. vous paraissent les mieux design es Nous vous prions aussi de bien vouloir prendre l’initiative de la formation ´ Anglais, Hollandais, Americain, ´ d’un Comite´ Italien, analogue aux comites ´ e´ prises Canadien,. . . , qui se forment.92 Les personnes, qui n’auraient pas et pour le Comite´ international, pourraient figurer dans cette seconde organi´ ´ que l’organisation sation nationale necessairement beaucoup moins limitee internationale. ´ Nous sommes ici de plus en plus enclins a` considerer la guerre comme ˆ ` longue. L’opinion publique est admirable, et le moral des devant etre tres ´ e´ meilleur. Tout le monde sent que c’est une lutte troupes n’a jamais et ˆ ´ Quelle triste mentalite´ que celle de ces supreme, et qu’il faut vaincre ou perir. Balkaniques, qui ne veulent pas comprendre que le triomphe germanique ´ serait leur esclavage definitif ! ` vive affection, Croyez, cher ami, a` mes sentiments de vieille et tres Emile Picard
Volterra to Hadamard n.p., 5 September 1915 (draft) Mon cher Ami, ´ J’ai su que vous appartenez a` une Commission qui s’occupe de repandre ´ a` l’etranger des publications de propagande se rapportant a` la guerre.93 En ´ Italie on a l’intention de faire des publications analogues et on desirait de les ´ repandre dans les pays neutres. ` vous distribuez vos brochures Pouvez-vous m’indiquer de quelle maniere ´ ˆ de le savoir pour faciliter notre tache. aux Etats-Unis94 ? Il serait interessant 92
A British Committee, with Lord Muir Mackenzie (1845–1930) as chairman, was formed to work in connection with the French Committee. Volterra was at the head of the Italian Committee; an American Committee – a chairman of this Committee was Herbert Clark Hoover (1874–1964) who became President of USA in 1929 – was founded as well as a Japanese Committee under the Prince Hiro-Hito. See Louis Picard, La Biblioth`eque de Louvain et le “furore teutonico”, Louvain, Ed. de la jeunesse catholique.
93 Volterra probably alludes to the Comit´e d’´etudes et de documents sur la guerre. This committee, composed of intellectuals was founded at the beginning of the war by Durkheim and Hadamard and was presided by the historian Ernest Lavisse. The declared objective was mainly to be in touch with the neutral countries. On Hadamard’s activity during the war, see J.-L.Chabert et Ch. Gilain: Jacques Hadamard, un itin´eraire a` travers la premi`ere guerre mondiale in [22]. 94
As already mentioned, Volterra had a strong relationship with the United-States. He had crossed the Atlantic several times before the war (see [24], Chapter 5), such as in 1912 when he was invited to inaugurate the Rice Institute of Houston, together with Borel. The same year he began a friendly
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
` vous avoir ecrit ´ Apres j’ai rec¸u une lettre de M. Soula95 qui me donne des bonnes nouvelles. ` bonne. Je sais qu’en France tout L’opinion publique chez nous est tres va bien. Les nouvelles de Russie n’ont pas fait beaucoup d’impression.96 ` que les allemands payeront bien cher leur avancee ´ en Pologne. Il J’espere ´ de tous les allies ´ faut au moment donne´ par des mouvements simultanes ´ ´ ´ ecraser definitivement ces execrables allemands et les rendre impuissants a` nuire a` l’humanite´ pour l’avenir. L’avenir est pour la quadruple entente. ´ Les pays balkaniques et l’Amerique sauront aussi comprendre quels sont ´ ´ ets ˆ de tous les peuples civilises ´ et mettre bien au dessus les veritables inter ´ ´ ets ˆ du moment la question universelle qui touche a` tout des miserables inter ´ l’avenir de l’humanite.
Hadamard to Volterra Plougasnou, n.d. [September 1915] Coran 3 Plougasnou ` (Finistere) Mon cher ami, ´ J’ecris a` M. Max Leclerc (librairie Armand Colin)97 qui s’est charge´ de ´ toute l’organisation materielle de notre propagande, de vous donner tous ´ les details possibles sur cette organisation. relationship with Griffith Evans (1887–1973) who had come to Rome in 1910 for a two years postdoctoral fellowship. Evans soon became a star on the American scientific stage and kept his contacts with Volterra until his death in 1940. The correspondence between Evans and Volterra, mostly written in Italian, is extremely interesting and certainly deserves to be examined. Just after Italy entered the war in May 1915, Evans wrote to Volterra on 22 July 1915: “We hoped Italy would not enter the war, even if the cause was a right one and high the ideals, for we did not want to learn the death of so many friends. But, as the war has been declared, may Italy now realize the dreams accumulated for so much time. The German behavior is not sympathetic to us either”. Until the USA decided to send troops in 1917, the problem of convincing them to abandon their neutrality soon became of major importance among the Allies. On the subject, see for example A. Kaspi: Les Etats-Unis d’Am´erique face a` la guerre en Europe in [4], pp. 943 et seq. See also ♥ 8. 95
On Soula, see footnote 46. On 8 July 1915, Soula had sent a letter to Volterra from the front where he was very enthusiastic about the Italian intervention, and once again, made comments about the solidarity between the Provence people and Italy.
96
After the defeat of Gorlice in June 1915, the Russian armies had retreated and left Poland entirely in the hands of the central empires. By October 1915 the Russian retreat had come to a definite halt along a line running from the Baltic Sea just west of Riga southward to Czernowitz (Chernovtsy) on the Romanian border. See [58].
97
Max Leclerc (1864–1932) was born in Paris and studied in Germany and England; he was a journalist and the director of the publishing house Armand-Colin (he had married Jeanne ArmandColin). He was also the secretary of the Conseil d’administration du Cercle de la Librairie, member of the “Chambre de Commerce de Paris” (1913–1920) and member of the Conseil d’Escompte de la Banque de Paris (from 1915 onwards).
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` Personnellement, je puis ajouter que notre collegue D.E. Smith de Columbia ` Octobre, avec un devouement ´ entier Univ.ty98 s’est mis a` ma disposition des ´ pour cooperer a` notre distribution aux Etats-Unis. Vous pourrez certainement user de lui, vous aussi; il ne marchande pas sa peine. ` de votre superbe Nous suivons tous ici avec admiration les progres ˆ ´ 99 Nous ne pouvions vous empecher tout d’abord, quelque confiance armee. ˆ ´ etant ´ ´ les avantages que nous eussions en elle, d’etre angoisses, donnes ´ formidables que la disposition du terrain reservait aux Autrichiens ; et voila` que ces obstacles sont comme s’ils ne comptaient pas ! Avec de pareils ´ comment n’aurait-on pas bientot ˆ raison de ces fous dangereux ? De allies, ´ e´ le monde entier quand nous nous reverrons. quel poids sera delivr ´ Votre bien cordialement devou e´ J. Hadamard
Volterra to Borel n.p., 27 December 1915 (draft) Mon cher Ami, ´ a` longtemps que je ne rec¸ois pas directement vos nouvelles mais Il y a dej j’en ai rec¸u par plusieurs de nos amis communs que j’ai vus dans plusieurs occasions. Nous avons beaucoup parle´ de vous avec M. Luchaire.100 J’ai pris la plus vive part au grand malheur qui vous a frappe´ par la mort de votre fils adoptif.101 Je vous exprime une fois encore mon plus profond regret pour cette douloureuse perte.
98
David Eugene Smith (1860–1944) was an American mathematician and educator, who became professor of mathematics at the Teachers College, Columbia University (1901).
99
Hadamard probably alludes to the first Italian offensive on the Isonzo, which seemed powerful, but eventually could not break the Austrian front and resulted in heavy losses.
100
The historian Julien Luchaire (1876–1962) was a prominent specialist of the Italian Renaissance. On him, see ♥ 9.
101
Fernand Lebeau (1889–1915), Borel’s adopted son, had been killed on 25 September 1915 in Champagne. Borel had sent an announcement to Volterra. On Fernand Lebeau’s death, see [39], pp. 165–166.
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´ e´ militarise´ 102 et que maintenant vous etes ˆ J’ai appris que vous avez et ` ´ chef du bureau des etudes sur les inventions103 qui fait partie du ministere ` occupe´ par les de l’Instruction publique. Je pense que vous serez tres ` important. Je fais partie depuis plusieurs travaux de ce bureau qui est tres ´ ´ mois de l’Institut d’aeronautique militaire.104 J’y ai fait beaucoup d’etudes ´ d’experiences et de calculs. On travaille avec une grande ardeur pour ´ ´ preparer tout ce qui est necessaire dans cette branche si importante de ´ l’armee. ` elev ´ e. ´ Nous sommes surs L’esprit public est tres ˆ de la victoire et nous ˆ ˆ e´ de vous dans la lutte que nous combattons sommes fiers d’etre a` cot ensemble pour sauver l’humanite´ de la barbarie et de l’esclavage. Aussi vous que moi nous avons travaille´ toute notre vie pour rapprocher nos deux pays. Je suis heureux de les voir combattre ensemble. ` que nous nous verrons bientot ˆ et que l’occasion de nous rapJ’espere procher en Italie ou en France ne tardera pas. ´ ˆ ´ au souvenir de Madame Borel et Madame Volterra desire d’etre rappelee ´ je vous prie de lui presenter mes hommages. Veuillez accepter, Monsieur, l’expression de toute mon affection et de toute mon estime. Vito Volterra
102
Borel was called to the army on February 1915. First attached to the Headquarters, he was after one month transfered to the 2nd Artillery Regiment. As soon as in May 1915 he was placed at the head of a section of location of German batteries by the sound, whose mission was to organize and exploit on the front of the 4th Army, the new techniques of electro-acoustic measures developed by Cotton and Weiss at the Ecole Normale.
103
On 29 October 1915, the mathematician Paul Painlev´e (1863–1933) was appointed Minister of Public Instruction in the new Government headed by Aristide Briand: on Painlev´e’s engagement in politics, one may consult [16]. Later on, becoming President of the Academy of Sciences on January 7th, 1918, Painlev´e gave a speech of investiture (published in the Comptes-Rendus (166, 1, 17–19, 1918), available on Gallica) which offers an interesting insight into Painlev´e’s views on the role of the scientist in new war conditions. On November 15th, 1915, Painlev´e asked Borel to come to Paris and to organize a new section of the ministery, the Service des Inventions int´eressant la D´efense Nationale (Bureau of the inventions related to national defense). To help him, Borel called his two friends the physicist Charles Maurain (1871–1967) and the mathematician Henri Lebesgue (1875–1941). It is during this period that the somewhat difficult relationship between Borel and Lebesgue turned sour. The two men would never reconcile afterwards. See [14]. 104 Volterra refers to the Istituto Centrale Aeronautico, founded by Crocco with Volterra’s help in 1908. See ♦ 4.
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Volterra to Picard Roma, 29 December 1915 Cher Monsieur et mon cher Ami, Je ne puis pas laisser passer le jour de l’an sans adresser a` vous et a` votre Famille l’expression de ma plus vive et affectueuse sympathie et mes ` ´ qui vient de s’ecouler ´ ´ e´ bien terrible pour vœux les plus sinceres. L’annee a et ` tres ` douloureuse. Tous vos amis, vous et elle vous a frappe´ d’une maniere tous ceux qui ont pour vous les sentiments d’estime et d’admiration que vos ´ grands merites ne peuvent manquer de susciter partout ont partage´ votre ˆ e´ des Alpes ainsi qu’en douleur. Veuillez avoir l’assurance que de ce cot France les sentiments de regret pour vos chers que vous avez perdus pen´ ´ e´ tres ` profonds. dant cette periode de guerre ont et ´ qui va commencer apporter a` vous et a` votre Famille des Puisse l’annee soulagements et des consolations. C’est le vœux le plus chaleureux que je fais. ´ La guerre s’etend et se prolonge mais l’extension et le prolongement ne ´ ´ font qu’affaiblir nos ennemis communs. La victoire de nos armees alliees ` final plus que de la confiance ne peut manquer. Nous avons pour le succes nous en avons la certitude. L’union de la France et de l’Italie se raffermit chaque jour sur les champs de bataille ainsi que dans tous les domaines ou` ˆ elles travaillent ensemble pour les memes buts de civilisation et de justice. ´ Je n’ai eu rien a` ajouter par rapport a` la liste que vous m’avez adressee ` il y a quelque temps relative au Comite´ international de la bibliotheque ´ e´ a` son prode Louvain. Je suis heureux d’en faire partie et d’avoir adher gramme. Je n’attends que les indications pour discuter ce qui se rapporte ` d’un comit e´ local. Des ` que vous ou le Ministre a` la constitution concrete ´ de Belgique voudront me donner les renseignements necessaires le comite´ ´ sera constitue!
Borel to Volterra Paris, 4 January 1916105 Mon cher ami, ´ e´ tres ` heureux de recevoir de vos nouvelles et de savoir que vous J’ai et travaillez aussi pour notre cause commune; je ne doute pas que vous ne ` grands services. Il a et ´ e´ officiellement question d’etablir ´ rendiez de tres une 105 Letterhead: Cabinet du Ministre de l’Instruction Publique, des Beaux-Arts et des Inventions int´eressant la D´efense Nationale (Office of the Minister of Public Instruction, fine arts, and inventions related to National defense). See footnote 103.
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´ j’espere ` que, liaison entre notre service d’inventions et ceux de nos allies; la` aussi, nous arriverons a` cette coordination des efforts qui est la princi´ ˆ pale force de nos ennemis, et a` laquelle les principes liberaux eux memes des trois grandes puissances occidentales ne vont pas sans opposer des obstacles, heureusement pas insurmontables. ´ d’avoir a` Rome un mathematicien ´ M.Painleve´ 106 m’a parle´ de votre desir ˆ franc¸ais et il va tacher de vous donner satisfaction le plus rapidement possible; je regrette bien vivement que mes occupations actuelles ne me perme´ e´ tres ` heureux ttent pas de m’absenter longuement de Paris; car j’aurais et de cette occasion de vous voir longuement. ` content et M. Painleve´ Viendrez-vous a` Paris cet hiver? J’en serais tres aussi. Ma femme me charge de la rappeler a` votre bon souvenir et a` celui de ´ mes respectueux Madame Volterra, a` laquelle je vous prie de faire agreer hommages. ´ ´ que resserre Croyez, je vous prie, a` mes sentiments d’inalterable amitie, encore la fraternite´ de nos pays dans une cause si noble. Emile Borel
Volterra to Hadamard Roma, 27 January 1916 (draft) Mon cher Ami ` un voyage dans le nord d’Italie. J’ai et ´ e´ Je viens de rentrer a` Rome apres ´ amene´ a` Milan ou` j’ai assiste´ et pris part aux memorables manifestations
106 On Painlev´e, see footnote 103. During a journey to Italy in December 1915, the deputy Charles Benoist met Volterra who asked him to transmit to Painlev´e, then minister of Public Instruction, his desire to have mathematical lectures from a prominent French mathematician in Rome in 1916. Charles Benoist (1861–1936) was a lawyer and a constitutionalist. From 1902 to 1919 he was member of Parliament and belonged to the radical party. Later on, in 1919, he became ambassador of France in Belgium. Benoist wrote to Volterra on January 4th, 1916 to tell him that he had finally met Painlev´e who proved very much in favor of the project. Benoist wrote that the mathematician would probably be Picard. In fact, as can be seen in the letter Picard sent to Volterra on January 28th, 1916 (see below), Picard declined the invitation, as well as Borel in the present letter. And it was eventually Hadamard who accepted it; Volterra wrote to Benoist on January 20th, 1916 that Hadamard had just sent a letter to him to get extra information. Hadamard went to Italy in May 1916, a journey described at length in the exchanges between Volterra and Hadamard of this time (see below).
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ˆ Franco Italiennes a` l’occasion de l’inauguration de l’hopital fonde´ par les souscriptions Franc¸aises.107 ´ C’est a` cause de mon voyage que je reponds avec quelque retard a` votre aimable lettre. Elle m’a fait le plus grand plaisir. Nous serons heureux de ` que vos hesitations ´ vous avoir a` Rome et j’espere cesseront. ´ ´ de votre sejour ´ Vous pourrez etablir la duree ici pour le temps que vous ´ voudrez, et pour ce qui se rapporte au nombre des conferences vous pour´ ˆ rez aussi l’etablir comme vous voudrez mais si vous etes presse´ comme ´ ´ vous venez de m’ecrire et si vous voulez donner a` vos conferences le car` de conferences ´ ´ erales ´ actere gen vous pourrez vous limiter a` une ou deux ´ ˆ ˆ semaines. L’epoque meilleure serait avant paques. Quant au sujet vous etes naturellement libre de le choisir car tout ce que vous exposerez aura de ´ et. ˆ Des conferences ´ l’inter sur le calcul des variations seraient accueillies avec le plus grand plaisir.108
Picard to Volterra Paris, 28 January 1916 Mon cher ami, Je suis bien en retard avec vous, d’autant que j’ai appris par M. Benoist l’offre que vous m’aviez fait faire de venir faire un cours a` Rome. Cette invi´ 109 J’ai eu le regret de tation me fut transmise officiellement par M. Painleve. ´ ´ par les malheurs qui ne pouvoir l’accepter. Ma sante´ est fortement ebranl ee ´ derniere, ` ´ ´ ere. ` m’ont frappe´ l’annee et je dois me soumettre a` un regime sev ´ De plus, j’ai encore trop d’inquietudes au sujet de mon fils et de mon gendre ´ M. Dunoyer, pour m’eloigner des miens et surtout de ma femme, qui aurait ´ e´ dans l’impossibilite´ de m’accompagner. Croyez bien que j’ai et ´ e´ fort triste et de refuser votre offre si flatteuse. ´ ´ a` En France, l’opinion publique est excellente. Nous sommes resign es ´ subir la guerre aussi longtemps qu’il faudra, malgre´ tant de vies precieuse ` qui disparaissent chaque jour. L’Allemagne s’usera, financierement et en
107
The second page of the Corriere della Sera (dated January 26, 1916) is completely devoted to “A day of Italian-French demonstrations in Milan”. The article contains the description of the visit of the French politicians – their speeches, which Italian authorities attended the ceremony, how the ladies were dressed, and so on – who came to Milan for the inauguration of a “French Hospital” founded with the contribution of 700 French. 108
There is another draft of the same letter (probably an older one) where, at this point, Volterra describes the situation of lectures in mathematics at Rome University:“For mathematical analysis, we have this year a substitute for M. Crudeli. After Lauricella’s death, we have no more permanent professor for analysis but only substitutes. M. Amoroso who presented the theory of functions, M. Armellini Differential equations and M. Crudeli this year exposes developments into series”.
109
See footnote 106.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ Si l’annee ´ 1916 ne voit pas la fin de la hommes, plus vite que les Allies. ´ suivante. L’essentiel est que le monde echappe ´ guerre, ce sera pour l’annee au cauchemar de la domination Germanique. Je pense que M. Imbart de la Tour vous enverra prochainement des indications au sujet de Louvain.110 Veuillez, cher ami, nous rappeler, ma femme et moi, au souvenir de Madame Volterra, et croire a` mes sentiments de vieille affection, Emile Picard
Hadamard to Volterra Paris, n.d. [January/February 1916] Mon cher ami, ´ d’avoir a` Rome un proPainleve´ 111 vient de me faire part de votre desir fesseur franc¸ais, et ajoute que vous avez bien voulu penser a` moi. Je n’ai pas besoin de vous dire combien je suis sensible a` votre appel. Vous savez, ´ d’autre part, avec quel plaisir sans melange je l’aurais accueilli en des temps ordinaires, et que retourner le plus souvent possible dans votre pays a tou´ e´ mon plus vif desir. ´ jours et Les objections, vous les comprendrez, et vous les aurez, je pense, ´ a` l’avance. Non seulement, comme chacun, je ne puis penser qu’a` devinees ´ ´ en est issue, de ce qui interesse la guerre – et il est vrai que votre idee sorte que ceci ne serait pas une objection – mais j’ai la joie et la fierte´ de ´ collaborer a` des travaux directement utiles a` la defense. Je suis attache´ a` la ˆ de laquelle, vous le savez, sont nouvelle direction des inventions, a` la tete ´ Painleve´ et Borel.112 places ` ´ l’idee ´ d’interrompre Je ne puis vous dire que j’envisage sans arriere-pens ee le travail que j’y poursuis. Une interruption aussi radicale que l’impliqueraient ´ ´ ´ pour a` la fois les distances et la necessit e´ d’orienter mon esprit – si eloign e, le moment, de la Science pure – vers un enseignement tel que je voudrais le donner a` l’Universite´ de Rome, ne me ferait-elle pas perdre contact avec ` ˆ les problemes dont j’ai commence´ a` m’occuper, en meme temps qu’ignorer ceux qui continueront a` se poser?
110
Unfortunately in Volterra’s archives the letters from Imbart de la Tour to Volterra are dated from 1918 onwards.
111 112
See footnote 106.
At that time, Painlev´e was minister of Public Education; therefore, Borel was the Director of the Office and Jean Baptiste Perrin (1870–1942) the assistant director. For a history of the Direction des Inventions see [50].
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D’autre part, je comprends avec vous toute l’importance qu’aurait, pour ´ nos deux pays, une affirmation sur le terrain scientifique, de leur solidarite. ` desireux ´ Je serais tres de pouvoir concilier ce devoir avec ceux dont je viens de vous parler. La question dominante, pour moi, dans ces conditions, est celle de la ´ de mon sejour ´ ´ je suis conduit a` insister pour duree a` Rome. Cette duree, ´ ´ e´ l’allonger en d’autre temps, et autant l’abreger autant que j’aurais desir que cela sera raisonnablement possible. Je commence donc par vous demander quelle sorte d’enseignement ´ minima que vous pensiez a` lui attribuer. vous concevez et quelle est la duree ˆ J’ajoute que, toujours au meme point de vue, je serais heureux de pou` a` voir reculer un peu dans la mesure du possible mon absence de maniere pouvoir apporter ma collaboration jusqu’au moment ou` ces travaux auront ´ a` rec¸u un commencement d’application. dej ` vivement que nous arriverons a` une organisation que vous satJ’espere isfasse et, avec, encore une fois mes remerciements les plus vifs et les plus ` amitie´ chaleureux, vous prie de croire a` ma sincere J. Hadamard
Hadamard to Volterra Paris, 12 February 1916 ` Ministere de l’Instruction Publique, des Beaux-Arts ´ et des Inventions interessant ´ la Defense Nationale Direction des Inventions Mon cher ami, ´ C’est a` moi de m’excuser d’avoir tant tarde´ a` vous repondre et, toute d’abord, a` vous exprimer ma reconnaissance pour l’obligeance si grande ´ avec laquelle vous avez accueilli mes desiderata, quelques compliques qu’ils fussent. Comme le principal d’entre ceux – ne pas quitter trop longtemps les travaux que je poursuis ici – rec¸oit toute satisfaction dans votre lettre, vous ´ pouvez considerer mon acceptation comme acquise. ´ ererais ´ En ce qui concerne la date, je pref sensiblement venir ´ ` Paques ˆ ´ immediatement apres qu’immediatement avant; je n’en fais cepen-
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´ a` mis dant pas une condition sine qua non, me rendant compte que j’ai dej ´ votre bonne volonte´ a` une large epreuve. ´ ´ Le chiffre de 6 conferences, reparties approximativement sur deux ´ semaines, vous semble-t il conforme a` ce que vous desirez? Je vous avoue que je ne songeais pas a` venir traiter a` Rome du Calcul des Variations. ´ Vous savez que les quelques remarques que j’ai pu faire a` cet egard ont surtout pour principe la subordination de Calcul des variations au Cal` et decisive ´ cul fonctionnel.113 Or, sur ce point, non seulement la premiere impulsion vous appartient, mais nous gardons tous le souvenir des Lec¸ons ´ recentes dans lesquelles, reprenant a` nouveau la question, vous l’avez ´ a` un haut point de perfection. Et je ne saurais davantage venir portee ´ ´ ´ des Savants exposer ma methode relative a` l’existence des extremales (Mem. ˆ ´ aux Annali pour le cen´ celle que j’ai donnee etrangers, 1907)114 ou meme ´ que ces travaux tenaire de Lagrange,115 sans me rappeler immediatement ´ e´ depass ´ ´ par ceux de M. Tonelli.116 ont et es ´ Je pourrais cependant, assurement, rassembler sur ce sujet un certain ´ ` plus fragmentaire. Peut-etre ˆ nombre de remarques isolees, de caractere me ` ´ eral ´ ´ sentirais-je plus “chez moi” en prenant pour theme gen la theorie des ´ ´ ees ´ ` ` si votre equations aux deriv partielles et du probleme de Cauchy. La, 117 ´ ´ ´ du moins puis-je emettre Memoire des Acta m’a servi de point de depart, ´ ´ e´ moi-meme ˆ la pretention d’y avoir ajoute´ quelque chose, sans avoir et pas ´ trop distance´ depuis. Je pourrais faire ou non un preambule sur la possibilite´ ` ` ´ ees ´ partielles. du probleme dont il s’agit et des autres problemes aux deriv
113
Hadamard thought of calculus of variations as a part of functional analysis, which becomes complete with the development of integral calculus. His ideas on the subject are expressed in J. Hadamard, “Le d´eveloppement et le rˆole scientifique du calcul fonctionnel,” in Oeuvres de Jacques Hadamard (vol. 1–4, CNRS ed., Paris, 1968) vol. 1, pp. 435–453.
114 It is the memoir which won the Prix Vaillant of 1907: Sur le probl`eme d’analyse relatif a` l’´equilibre des plaques e´ lastiques encastr´ees, M´emoires pr´esent´es par divers savants a` l’Acad´emie des Sciences, vol. 33, N. 4 (1908); in Œuvres, vol. 2, pp. 515–629. 115 J. Hadamard, La construction de Weierstrass et l’existence de l’extremum dans le probl`eme isop´erim´etrique, Annali di Matematica pura ed applicata, s. 3, vol. 21 (1913), pp. 251–287; in Œuvres, vol. 2, pp. 647–682. 116
Leonida Tonelli (1885–1946) was appointed professor of calculus at the University of Cagliari in 1913; in 1922 he moved to the University of Bologna and in 1930 to the University of Pisa. He made important contributions to the calculus of variations; in particular, he investigated socalled semi-continuous functionals and the existence of their maxima or minima in the years 1914– 1915. In this regard, we mention the remarkable paper: Sur une m´ethode directe du calcul des variations, Rendiconti del Circolo Matematico di Palermo, vol. 39 (1915), pp. 233–264; a summary of this paper is contained in a note published in the Comptes Rendus, vol. 158 (1914), pp. 1776– 1778. Here Tonelli extended and generalized Hadamard’s results by using absolutely continuous functions.
117 V. Volterra, Sur les e´ quations int´egro-diff´erentielles et leurs applications, Acta Mathematica, vol. 35 (1912), pp. 295–356.
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Vous savez, toutefois, mieux que moi ce qui convient a` mon futur auditoire ´ et, par consequent, vous serez bien aimable de me faire connaˆıtre votre sentiment. ´ Presentez, je vous prie, tous mes respects a` Madame Volterra, et croyez a` mes sentiments de vive amitie´ J. Hadamard
Picard to Volterra Paris, 14 February 1916 Cher ami, Usant de la liberte´ que vous avez bien voulu lui donner, M. Imbart de la Tour propose la liste suivante pour le Comite´ International Italien, relatif a` ` la reconstitution de la Bibliotheque de Louvain. Elle se compose de vingt personnes, plus un Comite´ d’honneur. M. Imbart de la Tour a cependant eu ´ des hesitations dans certains cas; voulez-vous avoir l’obligeance de faire dans ces cas les choix que vous jugerez les meilleurs. Vous trouverez aussi ´ de diverses villes dans la liste le souci de faire appel a` des personnalites ´ ´ Italiennes, et aussi a` des representants d’etudes diverses. Je crois que vous ´ avez les adhesions de toutes les personnes de la liste, sauf celles qui sont ´ comme rec¸ues directement. indiquees Pour le Comite´ National, M. Imbart de la Tour pense que vous pourriez en causer avec M. Meda et M.gr Duchesne,118 et aussi avec M. Van den Heuvel qui est au courant. Nous avons vu avec une grande joie l’admirable enthousiasme du peuple de Rome a` l’occasion du voyage de M. Briand.119 La coordination des
118
Filippo Meda (1869–1939) was lawyer, journalist and politician. He was a member of the Catholic movement. As a journalist he directed the Osservatore cattolico and founded the newspapers L’Italia (1912) and Civitas (1919). In 1909 he was elected a member of the Parliament and in 1915 Boselli – who was the Prime Minister – asked him to take part to the Ministry of Finance; he maintained this position until the end of the War. In 1923 he left politics since he was antifascist. Louis Duchesne (1843–1922) was a French Archbishop, as well as a teacher and a historian. He wrote the book Histoire ancienne de l’Eglise which the Pope Pius IX banned in 1912 – the Pope considered the book too modernist. 119
Aristide Briand (1862–1932) was a French diplomat and politician. At the beginning of his political career, he was a socialist and the secretary of the French Socialist Party from 1901 to 1904. In 1904 he founded, together with Jean Jaur`es, the newspaper L’Humanit´e. In 1906, when he was a member of the Parliament, he was expelled from the Socialist Party and founded his own party – the Republican Socialist Party. He was Prime Minister many times – in particular of the fourth government during the First World War. After the War he had many government mandates for about 16 years – as Prime Minister and Minister of Foreign Affairs.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ ` ´ et on peut operations va se trouver maintenant completement assuree, ´ ´ 1916 verra, sinon la fin de la guerre, du moins un pas esperer que l’annee ´ ´ decisif vers la victoire finale, sans laquelle aucune des puissances liguees ´ contre l’orgueil et la barbarie Germaniques ne deposera les armes. ` vive affection, Croyez, cher ami, a` mes sentiments de vieille et tres Emile Picard ` Italie (Comite´ de la Bibliotheque de Louvain) 1. Volterra ´ ´ 2. P. Boselli President de l’Academie des Sciences de Turin 3. Ruffini Recteur de l’Universite´ de Turin120 4. Somigliana ou Enrico d’Ovidio Mat. a` l’Univ. de Turin 5. un professeur a` l’Universite´ de Naples ? 6. un professeur a` l’Universite´ de Padoue (Luigi de Marchi ou Tamassia) 7. Millosevich Directeur de l’Observatoire royal.121 ´ ´ Secretaire de l’Academie des Lincei 8. Pigorini122 Prof. a` l’Universite´ de Rome.
As for Briand’s visit to Rome, on 11 February, the Corriere della Sera published an article entitled “The enthusiastic welcome of Briand in Rome”, where it is also reported the speech of the Italian Minister of Foreign Affairs Sidney Sonnino. Before Rome, Briand visited Turin too. Notices on Briand and his travel to Rome are reported in the Corriere for about a week. The problem faced by Briand from one side, and Salandra and Sonnino from the other side, concerned the War and how Italy could help the Allies even if it went to war against Austria only – and not against Germany (let us recall that war was declared to Germany only in August 1916). 120
Francesco Ruffini (1863–1934) was a lawyer and professor of history of law and ecclesiastical law at the University of Pavia, Genoa and Turin. He was also Rector of the University of Turin (1910–1913), and therefore Picard mistakenly mentioned his position in the present letter. He was a neutralist in the Italian debate of the intervention in war. He was elected Senator in 1914 and was Minister of Public Education during Boselli’s government (June 1916–October 1917). In 1931 he lost his chair, since he did not swear an oath of loyalty to Fascism. His ideas on the freedom of worship are published in the book Freedom of worship. History of an idea (La libert`a religiosa. Storia di un’idea) (1901).
121
Elia Millosevich (1848–1919) was an Italian astronomer. He studied at the University of Padua and in 1872 became professor of nautical astronomy at the Reale Istituto di Marina Mercantile in Venice. In 1879 he was offered the position of deputy director of the Osservatorio del Collegio Romano in Rome, and from 1902 until his death he was its director.
122
Luigi Pigorini (1842–1925) was an archaeologist who gave fundamental contributions to Italian prehistory. He is considered as the founder of the Italian paleontology and in 1875 founded – together with Pellegrino Strobel – the journal Bollettino di paleontologia italiana. In 1876 he was appointed professor of paleontology at the University of Rome and founded the Museo preistorico ed etnografico in Rome.
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´ ´ Secretaire adj. de l’Academie des Lincei 9. Stringher123 Directeur Gal de la Banque d’Italie. membre de l’Acad. des Lincei Recteur de l’Univ. de Rome 10. Tonelli124 a` ajouter: 11. un professeur a` l’Universite´ de Pise. M.Toniolo125 12. un professeur a` l’Universite´ de Bologna Righi?126 13. un professeur a` l’Universite´ de Milan (Beltrami ?)127 r 14. le D de la Bibl. Nationale. Rome 15. un critique d’art Monteverde128 ou le Dr Gal des Beaux Arts a` 129 Rome.– M. Ricci 16. un artiste musicien Leon Cavallo130 ou Bo¨ıto131
123
Bonaldo Stringher (1854–1930) graduated from the University of Venice in economics and taught at the University of Rome. He was a Treasury official from 1893 to 1898 and then undersecretary and Minister of the Treasury. He was appointed general director of the Bank of Italy in 1900 and, in 1928, became the first governor of the Bank of Italy.
124
Alberto Tonelli (1849–1921) studied at the University of Pisa; in 1877 he was appointed professor of Calculus at the University of Palermo and then moved to the University of Rome, where he was Rector for a long time. He mainly did research on analysis, number theory and topology.
125
Giuseppe Toniolo (1845–1918) was a famous sociologist and economist. He graduated from the University of Padua in law in 1867 and was assistant professor at the same university until 1872; then he moved to the universities of Venice, Modena and Pisa, where he was appointed full professor. In 1889 he founded the Unione Cattolica per gli studi sociali in Italia (Catholic Union for the Italian social studies). He was a devout Catholic and fought for a stronger involvement of Catholic people in politics and social life. 126
Augusto Righi (1850–1920) was an Italian physicist. He was appointed professor at the University of Palermo in 1880; in 1885 he moved to the University of Padua and in 1889 to the University of Bologna, where he taught until his death. In 1905 he was elected senator. His most important research concern electromagnetic waves in connection with light.
127
Luca Beltrami (1854–1933) was an architect who lived and worked in Milan. He designed some important buildings of the town.
128
Giulio Monteverde (1837–1917) was an important sculptor who mainly worked in Genoa and in Rome. He is considered as a representative of the verismo, the Italian movement whose aim is the representation of the objective reality. In 1889 he was elected Senator and was a member of many academies.
129
Corrado Ricci (1858–1934) was an archaeologist and an art historian. In 1898 he became Director of the Galleria Brera in Milan and from 1906 to 1919 was general Director of Antiques and fine arts. In 1923 he was elected Senator. 130
Ruggero Leoncavallo (1857–1919) was a well-known Italian composer; he was a representative of the verismo and the author of many lyrical dramas and operettas – Pagliacci (1892), Zaza (1900), Mameli (1916).
131
Arrigo Boito (1842–1918) was poet, composer and librettist, in particular for Verdi for whom he adapted Othello and Falstaff. His masterpiece as composer is the melodrama Mefistofele. He studied in Venice, and worked in Paris and Milan.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ ´ 17. deux historiens: Ferrari (Florence)132 + adhesion demandee directement ´ + adhesion rec¸ue 18. G. Ferrero (Rome)133 ´ ´ e´ demandes ´ directement Les adhesions de ces derniers ont et r ` ´ a Rome134 19. Marconi senat ´ 20. Journaliste politique. M. Meda135 +adhesion rec¸ue Comite´ d’honneur. Cel Maffi. Pisa136 idem Luzzatti137 personne de la famille royale —
´ adhesion rec¸ue
Volterra to Hadamard Signa, 22 February 1916 (draft) Mon cher ami J’ai rec¸u votre aimable lettre pendant que je suis en voyage. A mon retour ` ` a` present ´ a` Rome je parlerai avec mes collegues mais je puis vous dire des ˆ ´ erez ´ que vous etes parfaitement libre de traiter le sujet que vous pref et ´ ´ erez ´ ´ puisque vous m’ecrivez que vous pref de nous parler des equations ´ ´ ees ´ ˆ differentielles aux deriv partielles, vous pouvez arretez ce sujet pour ´ ´ celui de vos conferences. Je vous prie d’envoyer le sujet de vos conferences.
132
We were not able to precisely situate the mentioned person. In Volterra’s correspondance, one finds two items (one letter and a visit card) from Guglielmo Ferrari, who is probably the same. The letter, dated from 19 November 1917 is connected to lectures in Rome by a French professor from Lyon, Mignon. The letter proves that Ferrari was active in the association Intesa intellettuale founded later by Volterra (see ♥ 9) and in personal contacts with French officials such as A. Tondeur-Scheffler (see footnote 169) but we could not find out more about him.
133
See footnote 52.
134
Guglielmo Marconi (1874–1937) was a physicist and inventor. He is well-known for the invention of a system of wireless telegraphy which is very efficient. In 1896 he applied for the patent of his invention in London and obtained it. In 1897 he founded the Wireless Telegraph Trading Signal Company in London, which opened the first Wireless Office in the world. In 1927 he became the President of the National Research Council (CNR) and in 1930 the President of the Royal Academy of Italy. In 1930 he was also elected Senator.
135
See note 118.
136
Pietro Maffi (1858–1931) was an Italian Cardinal and astronomer. He taught mathematics and physics at the Seminary of Pavia and in 1900 founded the journal “Rivista di fisica, matematica e scienze naturali” which he directed until 1913. In 1903 he was appointed Archbishop of Pise and in 1907 Cardinal; in the same year he became the President of Vatican Observatory.
137
Luigi Luzzatti (1841–1927) studied law and graduated from the University of Padua. From 1867 to 1896 he was professor of constitutional law at the University of Padua. He was undersecretary in the Ministry of Agriculture in 1896, Minister of the Treasury four times, and Prime Minister from March 1909 to March 1910.
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´ ` bien. Le nombre de 6 conferences en deux semaines va tres ´ ´ Pour ce qui se rapporte a` l’epoque je vous avais ecrit que les jours qui ´ edent ` ˆ ` bien choisis, mais si vous prec les vacances de paques seraient tres ´ erez ´ ` paques ˆ ˆ pref apres vous etes parfaitement libre. ´ les Paques ˆ ` Ce sera alors au mois de Mai, car cette annee viennent tres tard. Or il est probable qu’au mois de Mai la guerre deviendra plus intense ´ plus tot ˆ que d’ordinaire et il et probablement les cours finiront cette annee aura quelques sessions d’examens. ` paques ˆ C’est pourquoi apres il faudrait choisir des semaines entre le 1er Mai et le 15 Mai.
Hadamard to Volterra Toulon, n.d. [March 1916] ˆ Victoria Hotel Toulon Chauffage central ´ ephone ´ tel 2-70 Mon cher ami, Je vous suis vraiment reconnaissant de vous plier avec tant de bonne ˆ a` mes demandes. Nous sommes tout a` fait d’accord, et il est difficile grace ˆ ´ de ne pas l’etre avec vous. Les conferences auront donc lieu du 1er au 15 ´ ees ´ Mai, au nombre de 6 et avec le titre: “Equations aux deriv partielles et ` probleme aux limites qui s’y rattachent”.138 En fait d’horaire je vous demanderais seulement – petite faiblesse per´ sonnelle – de ne pas me placer au commencement de la matinee. ´ Je ne tiens d’ailleurs pas specialement a` avoir toujours un jour d’intervalle ´ ererais ´ ˆ entre mes lec¸ons, et pref meme deux d’entre elles a` deux jours ´ ´ ´ ´ consecutifs, les deux autres etant separ ees par un jour. Tout cet arrange´ eral ´ ment est d’ailleurs subordonne´ a` votre commodite´ et a` l’horaire gen de ´ je me fie a` vous pour le regler ´ l’Universite: au mieux. ˆ mon cher ami, et croyez a` mes sentiments bien cordialement A bientot, ´ ´ devou es J. Hadamard
138
As it will be shown in the sequel, Hadamard was at some pains to decide on the title if his lectures.
78
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ sur la nouvelle attaque de l’ennemi, et Nous sommes tous rassures notre confiance ne fait, a` Dieu merci, qu’augmenter a` mesure que les jours passent.139
Borel to Volterra n.p., n.d. [March 1916140 ] M. et Mme Emile Borel avec nos plus douloureuses sympathies pour le grand malheur qui vous frappe.141
Picard to Volterra Paris, 15 March 1916 Mon cher ami, ´ Veuillez recevoir mes bien affectueuses condoleances a` l’occasion de ` la mort de Madame votre mere. Vous connaissez toute mon amitie´ pour ´ vous, et rien de ce qui vous concerne ne me laisse indifferent. Nous vivons ´ ` effroyable. helas! dans un temps ou` les deuils s’accumulent d’une maniere Ici bien peu de familles ne sont pas atteintes; ce sera la ranc¸on d’une victoire que l’on sent venir malgre´ les attaques furieuses d’un ennemi qui tente ses ` ´ ˆ meme ˆ dernieres chances et que la demence semble devoir perdre plus tot ´ qu’on ne le pense communement. ` sympathique souvenir. Ma femme envoie a` Madame Volterra son tres ´ Veuillez aussi lui presenter mes respectueux hommages et croire a` mes ´ ´ sentiments cordialement devou es Emile Picard
139
Hadamard probably alludes to the beginning of the battle of Verdun, which lasted in fact until December 1916. Between 6 and 15 March the battle for the Mort-homme took place and the French lines resisted to a violent German offensive.
140 141
See footnote 141. Visiting card of M. et Mme Emile Borel 45, rue d’Ulm Ve
On March 4, 1916 Volterra’s mother (Angelica Almagi`a Volterra) died of the complications of a bladder infection. See [23], pp. 179–180.
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Hadamard to Volterra Paris, 16 March 1916 Mon cher ami Je vous ai envoye´ ma lettre avant de recevoir l’annonce de deuil qui vous ` En ce moment ou` nous sentons frappe.142 J’y prends une part bien sincere. ´ que toutes nos emotions sont communes, les douleurs de nos amis nous atteignent plus que jamais. Madame Hadamard se joint a` moi pour vous envoyer, a` vous et a` Madame ´ ` Volterra, l’expression de nos condoleances bien vives et de notre sincere sympathie J. Hadamard
Hadamard to Volterra Paris, n.d. [March 1916] Cher ami, 143 ´ Puis je vous Je vous ai donne´ le sujet de mes prochaines conferences. ´ ´ demander de ne pas considerer cette indication comme definitive, a` moins ´ a` fait usage? que vous n’en ayez dej Je puis bien vous donner le motif de cette demande. Je suis quelque ´ peu confus de me presenter devant mon auditoire, sans autre bagage, ou ` que ce qui figure dej ´ a` dans des memoires ´ ´ a` peu pres, anterieurs, ainsi que ˆ je vais sans doute etre force´ de le faire, ayant songe´ depuis 1 an et demi ` Il a ecrit ´ le a` tout autre chose qu’a` la guerre.144 La phrase est bien celle la! contraire de ce qu’il voulait. . . ´ Si je pouvais, malgre´ tout, donner un developpement nouveau a` certaines ´ recherches anterieures, je vous avoue que j’en serais plus satisfait. Il y a peu de chances a` cela et il est peu probable que je puisse faire aboutir en ce ´ moment des calculs dont je n’etais pas sorti en temps de paix. – Je compte ´ vous fixer la` dessus sous peu de jours. Bien entendu, si l’annonce precise du sujet devenait urgente, voudriez vous me le faire savoir? Bien cordialement a` vous J. Hadamard 142
See footnote 141.
143
See footnote 138.
144
Sic. Hadamard obviously wanted to write the contrary, namely that he had thought only of the war for one and a half years.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Hadamard to Volterra Paris, 3 April 1916 ` Ministere de l’Instruction Publique, des Beaux-Arts ´ et des Inventions interessant ´ la Defense Nationale Direction des Inventions Cher ami, ˆ Je commence par vous donner le titre de lec¸ons que je vous ai peut etre ´ ´ ees ´ paraux deriv fait attendre trop longtemps. Le libelle suivant : equations tielles et mouvements par ondes145 me permettra d’ajouter, au besoin, les ´ complements auxquels je songe, et je puis donc vous le proposer. ´ ´ Je desire, d’autre part, vous entretenir d’un sujet different, auquel je porte ´ ´ et. ˆ egalement un grand inter ´ ` vive que rencontre le On a fini par s’emouvoir, ici, de l’opposition tres ˆ mouvement pro-allie´ parmi la population juive des Etats-Unis.146 Vous n’etes ´ pas sans savoir comment la presse allemande a su exploiter les difficultes de la situation des Juifs en Russie. Nous sentons tous combien cette proˆ ´ pagande peut nous etre prejudiciable. Songez qu’il y va, non seulement de ´ a` important, mais meme ˆ notre force morale, ce qui est dej de notre force ´ materielle. ´ e´ decid ´ ee, ´ et cela avec l’autorisation et meme ˆ Une action a donc et l’approbation de notre gouvernement. Il s’agit de faire comprendre a` nos ´ correspondants de l’autre cote´ de l’Atlantique que les maux qui les revoltent ´ – et terriblement aggraves ´ – par un triomphe allene seraient qu’aggraves ´ ´ ` les manifestations mand, tandis qu’il nous est legitime d’esperer, d’apres ´ er ´ ees ´ de l’opinion publique en Russie, que la victoire des allies ´ assurera reit ´ certainement aux Juifs de ce pays une situation acceptable. Nous esperons ´ ` egalement leur faire sentir que les puissances de l’Entente pensent, des ` maintenant, a` examiner les problemes qui concernent cette situation avec ´ et ˆ qui ne sera pas purement theorique. ´ un inter ` ce qui prec ´ ede, ` Je n’ai pas besoin, apres de vous dire que le but poursuivi est national et non confessionnel.
145
J. Hadamard, Lec¸ons sur la propagation des ondes et les e´ quations de l’hydrodynamique, Paris, Hermann, 1903. This book became soon a classical work on the subject, which represented the starting point of further research on wave theory for a long time.
146
On all this discussion, see ♥ 8.
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´ entierement ` ´ On a fonde´ un comite, compose´ d’Israelites franc¸ais, destine´ ´ a` se mettre en rapport avec deux journaux juifs americains, a` les renseigner ´ et ˆ qui se manifeste, dans les pays allies, ´ envers la cause juive et, sur l’inter inversement, a` recevoir les renseignements qu’ils nous communiqueront sur ´ ´ l’etat de l’opinion americaine. ´ ˆ ´ Nous serions heureux de voir se creer, dans le meme but, des comites ´ et le but de la presente ´ analogues dans tous les pays allies, lettre est de ˆ du vous demander si vous ne seriez pas dispose´ a` vous mettre a` la tete Comite´ Italian.147 ´ ´ Je n’entrerai pas dans plus de details: je tiens a` ceder la parole a` mon ´ 148 que vous avez vu chez moi et qui, faisant partie du Comite´ ami S. Levi, ` pres. ` franc¸ais, suit cette affaire de tres Je vous remercie a` l’avance de vouloir bien me faire connaˆıtre votre avis ˆ vous prie sur cette question et, on attendant le plaisir de vous voir bientot, de me croire ´ Votre bien cordialement devou e´ J. Hadamard
Picard to Volterra Paris, 14 April 1916 Cher ami, Vous seriez bien aimable de m’envoyer la liste, que vous avez duˆ ´ ˆ definitivement arreter, des membres du Comite´ International relatif a` la ` ´ reconstitution de la Bibliotheque de Louvain. M. Imbart de la Tour desirerait ´ etant ´ ´ ´ chez vivement l’avoir, les autres Comites definitivement constitues ´ et les pays amis. Seules, la Hollande et la Suede ` les Allies montrent peu ` ce que me ´ ´ 149 D’apres d’empressement, ce qui d’ailleurs ne m’a pas etonn e.
147
At the head of the Italian Committee was Filippo De Filippi (1869–1938). He was a doctor, appointed professor of medicine at the University of Bologna (1896) and at the University of Genoa (1900). He also loved explorings and was an accomplished alpinist; he was asked by Italian government to explore many areas of Alaska, East Europe and Tibet, and he wrote reports of his explorations published in many languages. He enrolled as a volunteer during the First World War and worked as a doctor and inspector of the Croce Rossa Italiana. In 1921 he left Rome and moved near to Florence, where he went on with his geographical studies and reports, and worked as a member of the Italian geographic Committee. See ♥ 8.
148
Sylvain L´evi (1863–1935) was an orientalist and indologist. He published important books on the subject and was professor at the Coll`ege de France. See ♥ 8. 149
It is seen that Picard’s distrust – if not hostility – toward neutral countries, appeared soon during the war. Neutrality was considered by him as support for the Central Empires, a slightly different
82
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dit M. Imbart de la Tour, vous avez duˆ recevoir la visite de M.gr Duchesne,150 qui vous aura parle´ de la question de Louvain. Quant au Comite´ National Italien, je pense que vous avez commence´ a` vous en occuper. ˆ Je suis bien fatigue´ depuis quelque temps, maladie morale plus peut-etre ´ ´ que physique. Je ne puis me detacher de mes tristes souvenirs, et l’etat de ´ sante´ de ma femme n’est pas pour me reconforter. Que les temps sont loin, ´ ou, chez vous a` Albano! ` tranquilles et heureux, nous dejeunions ´ ´ Croyez, cher ami, a` mes sentiments affectueusement devou es, Emile Picard
Volterra to Hadamard Torino, n.d. [April 1916151 ] ´ erable ´ ´ egraphier ´ ` Pref Mardi Jeudi Vendredi. Veuillez tel date premiere ´ ´ ` gen ´ eral ´ pour invitations autorites. ´ conference desirable caractere Volterra
Hadamard to Volterra Paris, n.d. [April 1916] Mon cher ami, ´ eche, ˆ Nous avons rec¸u votre dep et, a` l’heure ou` ceci vous parviendra, ´ vous aurez egalement rec¸u mon acceptation officielle. En fait de jours, puisque vous me donnez si aimablement le choix, je vous proposerais Mercredi, Vendredi et Samedi. Le Mercredi aurait – excusez ´ cet aveu depouill e´ d’artifice – l’avantage de ne me faire commencer que ´ le 3 et de me donner par consequent, pour me retourner, un temps dont,
view from Borel’s (see above Borel’s letter from 4 November 1914). This distrust even increased at the end of the war, and was used by Picard as a pretext to take the International Congress of Mathematicians of 1920 away from Sweden where it was originally supposed to happen. See below footnote 313. 150 151
See footnote 118.
The present letter is in fact a telegram sent by Volterra to Hadamard from the “Grand Hotel Ligure et d’Angleterre”, Torino.
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naturellement, je me trouve avoir grand besoin. Mais, bien entendu, si cette ´ Mardi, Jeudi et Vendredi, pour exemple, distribution soulevait des difficultes, me conviendrait aussi. ˆ ´ erable ´ Le Mercredi et le Vendredi, 10h 1/2 ou 10h 3/4 serait peut etre pref ´ ´ a` 11h , pour le cas ou` ma conference devait depasser un peu une heure. Toutefois, je ne sais trop dans quelle mesure les habitudes de mon auditoire s’accommoderaient de cette prolongation: c’est un point dont nous recauserons chez vous. ` midi (3h ou 4h ) sans objection Pour le Samedi, je vous proposerai l’apres ´ definitive contre le matin. Sur quoi, il ne me reste plus que a` arriver. Si quelqu’un m’avait dit, ´ que je quitterais, sans trop de regret, ma au commencement de l’annee, ´ besogne presente pour voyager, je ne l’aurais pas cru. Il est vrai qu’a` ce ˆ moment je n’aurais pas cru etre appele´ par votre pays et venir vous y retrouver. ´ Presentez tous mes respects a` Madame Volterra et croyez moi ´ Votre bien amicalement devou e´ J. Hadamard
Volterra to Hadamard Torino, 18 April 1916 Mon cher Ami, J’ai fait faire une circulaire que j’ai distribue´ aux professeurs de 152 ´ ´ pour annoncer vos conferences ´ mathematiques des Universites ` Le ministre de l’Instruction Publique en a parle´ aussi a ses collegues Salandra et Sonnino)153 et on en a rec¸u la meilleure impression. 152
Volterra had indeed been quite active to advertise Hadamard’s journey. On 7 April 1916, the Italian Minister for Public Instruction Pasquale Grippo wrote to him: “I have no objection to consenting that Prof. Hadamard of the Institute of France give a series of lectures at this Faculty of Sciences on subjects of higher mathematics. A similar request has been made by other faculties of sciences of the Kingdom and I did not hesitate to satisfy it, glad that our higher institutes can enjoy the collaboration of a prominent scholar of the allied country.”. On 15 April 1916, as he mentions in the present letter, Volterra sent the following circular letter to the Italian mathematicians as Director of the Faculty of Sciences of the University of Rome: “I am pleased to communicate to You that Prof. Jacques Hadamard of the ‘Coll`ege de France’ will give six lectures at this Faculty on questions of higher analysis (from 1 to 15 May). Professors and scholar of mathematics from other universities are very welcome; therefore, I invite You to inform them and your students.”
153
Antonio Salandra (1853–1931) was the Prime Minister of Italy from March 1914 to June 1916; he played a fundamental role in the intervention of Italy in World War 1 together with his Foreign Secretary Sidney Sonnino (1847–1922). They both were Conservative. See ♦ 5.
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D’accord avec M. Luchaire qui en avait aussi parle´ au Directeur de ´ egraphi ´ l’Instruction Publique a` Paris j’ai tel e´ au Ministre a` Paris annonc¸ant ˆ une lettre officielle qui arrivera peut etre en retard a` cause des bureaux ou` ´ eral ´ ` vite; car cette lettre officielle les affaires ne marchent pas en gen tres ` de l’Instruction publique154 passera par notre ministere ` occupe´ pour les dirigeables. Je suis toujours a` Turin ou` je suis tres ´ ` longs voyages. Je voyage par les voies aeriennes en faisant de tres ` de vous voir bientot ˆ en Italie. J’espere ` bien. Les boches sont partout repousses. ´ La guerre marche tres ´ Franc¸aise se couvre de gloire a` Verdun. Notre population ainsi L’armee ´ des meilleures dispositions et que toutes les classes sociales sont animees ` vaillamment. nos soldats se battent tres
Hadamard to Volterra Paris, 21 April 1916 Mon cher ami, ´ ´ comprenant mes proposiJe viens de vous envoyer une lettre detaill ee tions d’horaires (Mercredi 10h 3/4, Vendredi 10h 3/4, Samedi 3 ou 4h , ou a` ´ defaut, Mardi, Jeudi, Vendredi). Vous avez probablement cette lettre en main lorsque celle-ci vous arrivera. Mais j’avais oublie´ que je serai suivant toutes ˆ ` Toulon) et ´ dans la rade de Toulon (G.d Hotel, Tamaris, pres les probabilites c’est de cet endroit que je partirai pour Rome. Puis je vous demander de ´ ˆ m’envoyer une reponse a` cet endroit, en meme temps qu’a` Paris? Tous mes remerciements a` l’avance. Bien cordialement a` vous J. Hadamard
154
Volterra wrote the following letter to Paul Painlev´e, Minister of Public Instruction, as dean of the Faculty of Science in Rome and Senator of the Italian Kingdom: “Mr. Minister, As for the request that has been orally made to You by the deputy Ch. Benoist in the name of Rome University and which Julien Luchaire – Director of the French Institute of Florence – spoke about with the Director of the Higher Education, I have the honor to ask you to authorize Hadamard, Professor at the University of Paris, to come to Rome from 1 to 15 May to give a series of lectures at our Faculty of Sciences. I want you to know – on behalf of my colleagues and myself – that we shall be happy and feel honored to have with us a French colleague, who is an illustrious representative of the University of Paris. We hope that the relationships between the universities of the two countries will become more frequent and more fruitful after this first experience.” On Benoist, see footnote 106. On Luchaire, see footnote 100 and ♥ 9. Luchaire apparently followed Hadamard’s journey to Rome with great interest. After his departure, he wrote to Volterra on 24 May 1916 the following lines: “I am glad of the great success of Hadamard’s lecture. I deeply hope that next year it will be possible to undertake once again this wonderful initiative on a larger scale. I look forward to seeing you in Paris in a few days. We shall probably meet in Turin at the departure of the train going to France.”
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Hadamard to Volterra Paris, 27 April 1916 ` Ministere de l’Instruction Publique des Beaux-Arts ´ et des Inventions interessant ´ la Defense Nationale Direction des Inventions Mon cher ami, ` n’avoir pas trop derang ´ J’espere e´ vos plans en remettant au Jeudi 4 ma ` conference ´ ´ eche ˆ premiere a` Rome. Votre dep ne me laissait pas d’autre ˆ ˆ pour solution. Avant de la recevoir, c’est tout juste si je comptais etre pret ´ ´ mes conferences de mathematiques proprement dites. L’improvisation d’une ´ ´ et ˆ gen ´ eral ´ conference d’inter est pour moi une assez grosse affaire. Je m’y ´ mets instantanement “a` toute vapeur”. Mais, de vous a` moi, je m’excuse ´ ´ par avance d’apporter quelque chose de forcement assez mediocre. Il est ´ ´ a` Rome, comme vous le fait prevoir ´ egalement probable que, a` mon arrivee ´ eche, ˆ ma dep j’aie quelques renseignements a` vous demander. J’y serai ` la matinee. ´ Mercredi matin et viendrai vous voir des Il me reste a` vous demander une autre service. Pourrai je par votre ´ les quelques livres a` dessous entremise, trouver a` mon arrivee, ´ Lagrange. Mecanique analytique. ´ ´ ´ t. I) conde l’Academie de Sciences (2e serie, X Le tome des Memoires ´ tenant le Memoire de Poisson sur les ondes.155 Lamb, Treatise on Hydrodynamics.156 ` ´ (1911) (ou, ce qui revient au Les Theses de Gevrey (1913) et de Paul Levy ´ ´ des Annales Scient. de l’Ecole Normale contenant l’une meme, le numero et le n. du Journal de l’Ecole Polytechnique contenant l’autre).157 Annali di Matematica 1898.
155
Sim´eon-Denis Poisson, M´emoire sur la Th´eorie des Ondes, M´emoire de l’Acad´emie des Science, 1, 1816.
156 157
H. Lamb, Hydrodynamics, Cambridge, Cambridge University Press, 1892.
M. Gevrey, Sur la nature analytiques des solutions des e´ quations a` d´eriv´ees partielles, Annales de l’Ecole Normale Sup´erieure, s. 3, vol. 35 (1918), pp. 129–190; in this paper there is a footnote, where Gevrey explains that his memoir had to be published in 1914, but its publication was interrupted because of the War. P. L´evy, Sur les e´ quations int´egro-diff´erentielles d´efinissant des fonctions des lignes, Paris, Gauthier-Villars, 1911; ou Journal de l’Ecole Polytechnique, s. 2, vol. 17 (1913), pp. 1–120.
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´ Celui qui est marque´ d’une croix (Memoire de Poisson) vous donnerait ˆ peut etre de la peine (il m’en a donne´ a` Paris), je crois donc utile d’ajouter qu’il ne m’est pas indispensable. Quant au Circolo,158 que j’utiliserai pas mal a` partir de 1910 surtout, je ˆ pense de n’avoir meme pas besoin de vous en parler pour le trouver. ´ Je vous derange beaucoup et m’en excuse infiniment. Ma seule excuse ˆ avec laquelle j’ai duˆ preparer ´ ´ est dans la hate mon depart. ´ Merci a` l’avance. Croyez a` mes meilleures amities J. Hadamard
Picard to Volterra Paris, 9 May 1916 Cher ami, Vous serez bien aimable de m’envoyer la liste des membres Italiens ´ pour le Comite´ International de Louvain, quand vous l’aurez definitivement ´ Je vous demande pardon de vous ennuyer encore avec cette dressee. affaire, mais je suis un peu presse´ par M. Imbart de la Tour. ˆ ´ a` dit Peut-etre M. Hadamard est-il en ce moment a` Rome. Je vous ai dej ´ eprouv ´ ´ par les malheurs qui m’ont combien j’avais regrette´ que ma sante, ee ´ frappe´ et les inquietudes que j’ai encore (notamment la sante´ de ma femme), ´ ne m’avait pas permis de me rendre a` votre aimable invitation. Esperons que des jours moins tristes viendront, quoique pour moi la vie ne sera jamais plus ´ e. ´ ce qu’elle a et Veuillez nous rappeler, ma femme et moi, au souvenir de Madame Volterra et croire, cher ami, a` toute mon affection, Emile Picard
Volterra to Picard n.p., n.d. [May 1916] (draft) Mon cher Ami, ´ Comme j’avais eu l’honneur de vous ecrire le choix des membres du ` bien. Apres ` la Comite´ International pour l’Universite´ de Louvain allait tres 158
He refers to the Rendiconti del Circolo Matematico di Palermo.
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` concertation un certain nombre entre eux sont aussi Ministres en derniere ˆ ´ ´ Italie. J’en suis heureux car ainsi l’oeuvre du comite´ pourra etre rehauss ee ´ par la position officielle dans le cabinet de plusieurs membres du Comite. ´ ´ Pour ce qui se rapporte au Comite´ national Italien dont je m’etais reserv e´ ` lettre il y a une circonstance qui se presente ´ ` favorable dans ma derniere tres ´ dans ce moment. C’est justement a` cause du projet qui etait alors en voie ´ ´ ´ ´ Nous avons fondee ´ en Italie une Associd’execution que je m’etais reserv e. ´ et amis.159 Cette Assoation pour l’entente intellectuelle avec les pays allies ´ et elle a commence´ ses travaux. Nous ciation est maintenant constituee ´ ˆ des resultats ´ avons l’appui du gouvernement. Nous esperons obtenir bientot ´ pratiques dans toutes les branches de l’activite´ intellectuelle. Nous desirons ´ et au conforter les liens intellectuels avec la France et les autres pays allies ˆ meme temps lutter contre nos ennemis communs dans ce domaine aussi. ´ ´ J’ai porte´ dans une des premiers seance de notre Comite´ executif dont je ´ ´ suis le President le vœu d’adhesion de notre Association a` l’œuvre de recon` ´ ´ e´ donnee ´ avec le stitution de la Bibliotheque de Louvain. Cette adhesion a et plus grand enthousiasme. Je crois que cette Association puisse mieux que ˆ e´ du Comite´ International pour toute autre constituer le Comite´ Italien a` cot Louvain. ´ Je desire seulement avoir votre approbation pour continuer dans cette orientation. ˆ ´ depuis longtemps mais elle n’a pu se L’Association devait etre fondee ` ´ e´ tres ` occupe´ dans les derniers constituer que tout dernierement. J’ai et ´ e´ toujours hors de Rome. Ce n’est que depuis peu de jours temps et j’ai et ´ Je m’occupe maintenant d’aeronautique ´ que je suis rentre. et j’ai eu l’ennui de passer beaucoup de temps dans le Nord d’Italie en faisant beaucoup ´ de voyages aeriens. Je suis heureux de pouvoir mettre a` disposition de ma ` Je patrie les connaissances techniques que j’ai acquis dans ma carriere. 160 ´ dans le corps technique du Genie. ´ fais partie de l’armee ` bien. Nos ennemis ont perdu l’initiative dans la La guerre marche tres ` important. Il n’y a pas de mots pour conduite de la guerre ce qui est tres ´ franc¸aise. Son hero¨ ´ ısme a` Verdun exprimer notre admiration pour l’armee ´ ´ ´ ´ a depasse tout hero¨ısme connu. La resistance dans cet endroit a sauve´ la ´ erale. ´ situation gen ˆ Mais il ne faut pas se hater pour la paix. Il faut beaucoup de patience et la ´ ´ victoire definitive avec l’ecrasement de nos ennemis ne pourra pas manquer.
159
This Society, founded by Volterra, is deeply connected with the Comit´e du Livre (see note 169 and ♥ 9); it can be considered as one of the enterprises aiming to reinforcing the cultural and academic relations between Italy and France. (See ♥ 10.) On April 1918 this Society published his own journal L’intesa Intellettuale, with Andrea Galante (University of Bologna) as director and with the help of the publishing house Zanichelli in Bologna. 160
See note 85.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
J’ai l’honneur de vous envoyer quelques brochures. Ce sont de travaux ´ en guerre. Maintenant je travaille aussi et je que j’ai fait avant notre entree ´ dois faire beaucoup de mathematiques mais hors de la science pure. ` recevoir [the text is interrupted here] J’espere
Hadamard to Volterra Rome, n.d. [May 1916] Eden Hotel – Rome Franz Nistelweck Mon cher ami, ´ Je n’ai pas, lorsque je viens [d’] avoir le plaisir de dejeuner avec vous, oublie´ moins de quatre choses ´ le peu – vous le 1o de vous remettre ces petits tirages part, representant ´ savez – que j’ai fait recemment; 2o de vous demander si vous aurez le temps de jeter d’ici Mardi un coup d’oeil sur les papiers de la Ligue des Dts de l’Homme161 pour me dire votre impression; ´ 3o de vous reparler du Comite´ de Florence afin d’arriver a` des precisions; ˆ ´ 4o de meme de vous reparler des periodiques italiens – Ist. Lombardo, Ist. Veneto162 et partt Nuovo Cimento: question dont nous avons parle´ en chemin de fer. ´ Si j’ai le plaisir de vous voir a` dejeuner Mardi matin nous pourrons reparler de tout cela et je vous demanderai de vouloir bien me consacrer une minute a` cet effet. ˆ ˆ ´ ` Sinon peut etre aurez vous – meme etant donne´ que votre temps est tres ` pris a` Turin – une indication a` me donner, fut-ce celle du collegue avec qui ˆ je pourrais en parler utilement. Bien amicalt a` vous J. H
161 162
See note 184.
Rendiconti del Reale Istituto Lombardo di Scienze e Lettere; Atti del Reale Istituto Veneto di Scienze, Lettere ed Arti.
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Hadamard to Virginia Volterra n.p., n.d. [later than 20 May 1916] Madame, Je sais la peine que vous avez prise pour me faire parvenir, par ´ l’intermediaire de M. Fano,163 les nouvelles rec¸ues de Paris, et tiens a` vous en remercier du fond du cœur. ˆ ´ eche ˆ Vous avez peut etre devine´ que la dep que vous avez connue ´ ´ e. ´ Mon fils est mort, tue´ a` peu pres ` sur le coup, pres ` de attenuait la verit ´ ıquement comme il n’avait cesse´ de le faire Verdun, en combattant hero¨ ´ depuis plus d’un an – il s’etait mis, volontairement, a` la fonction la plus dangereuse.164 Puis je vous demander de communiquer cette nouvelle a` M. Volterra et ˆ en ce moment, oublier l’accueil aussi a` M. Castelnuovo.165 Je ne puis, meme que j’ai rec¸u de tous deux. ´ Croyez a` mes sentiments profondement respectueux J. Hadamard
Hadamard to Volterra n.p., n.d. [June 1916] Mon cher ami, Merci bien vivement de la sympathie que Madame Volterra et vous ´ temoignez dans mon horrible malheur. ´ Pendant le trop rapide sejour que j’ai fait a` Rome, je vous ai vu tous, ` mes amis italiens, sensibles a nos espoirs et a` nos angoisses, que je ne ` si cruelles a` si bref delai. ´ soupc¸onnais pas a` ce moment-la, 163
Gino Fano (1871–1952) was a mathematician, professor at the University of Turin from 1901. The text of the telegram sent to Volterra’s wife, Virginia, is the following: “Telefonato iersera Genova risultandomi Hadamard tuttora gi`a informato riparte oggi. Fano” (“Phoned yesterday in the evening in Genoa when I knew that Hadamard had been informed. He leaves today. Fano”).
164
The sous-lieutenant Pierre Hadamard (1894–1916) was killed on 18 May 1916 at Esme-en-Argonne near Verdun during the assault of the “Cote 304”. See http://vinny03.club.fr/gg/fichreg/rmz3bis.htm for details on this assault. See also the subsequent letter.
165
Guido Castelnuovo (1865–1952) was a mathematician who gave fundamental contributions to algebraic geometry. He graduated from the University of Padua in 1886 and then moved to the University of Rome (with Luigi Cremona) and to the University of Turin (with Enrico d’Ovidio and Corrado Segre). In 1891 he was appointed professor of analytical and projective geometry at the University of Rome.
90
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Je suis assez sur ˆ de votre amitie´ pour vous devoir et me devoir de vous faire connaˆıtre les circonstances dans lesquelles est mort mon fils. Je joins ´ a` cette lettre la copie de celle que m’a ecrite son colonel, et qui met de la fierte´ dans ma douleur.166
166
Hadamard, back in Paris, received the following letter from his son’s superiors, which he copied and transmitted to Volterra, along with the present letter. We reproduce it below. The fact that Hadamard wished to transmit such a letter to his Italian friends is an interesting and illustrates profoundly how people faced bereavements during the war. Colonel Gascouin Commandant of Artillery of the Sector of Fight
Sir, Now that I have left the sector, I want to express to you my pain and my admiration for the heroic death of your dear son, the second lieutenant Hadamard, and I beg you to accept my deep and sympathetic condolences. It was on May 18th: the Zouaves had attacked at 2.30 and reached the top of 304. I had called him at 8 o’clock in order to ask him to go to the new trenches, taken by the Zouaves, and to look for an observation post where we could get an idea of where the shells of the small 75 mm mortars targeted on the northern slope of 304 had fallen. Only in the evening did I know that there was no news of him and it was feared he had been killed. Here is what had in fact happened according to Captain Gardies, some soldiers and the Zouaves; after he had stayed in the trenches looking for a place that could serve as an observation post, he turned back, unable to find anything suitable. At that moment there was the noise of a counter-attack against the Zouaves whom he had just left. His mission was finished. However, he could not accept that an officer could witness a counter-attack without taking part in it. Therefore, he climbed back, took a rifle and was killed among the Zouaves, whom he urged and encouraged with his example. I have lost several officers (almost one each day) during this bitter affair of Verdun: I know no one who died in such an heroic way, arms in hand, going above and beyond his duty. I immediately suggested his name for a mention in dispatches. In the names of the officers of Artillery of the 9th Corps, I wish to express to you the affectionate and admiring memory we have of your dear son and to ask you to accept our deepest and most respectful condolences. Colonel Gascouin For completeness, and because the death of Hadamard’s second son Etienne, also killed during Verdun battle in July 1916 is not referred to in the correspondence, we also transcribe a second letter sent by Hadamard to Volterra which is kept together with the former one at the Lincei archives. The letter is from Etienne’s superior. Vesoul, 18 July 1916 Sir, I would have been glad to see you during my rapid passage through Paris maybe someone told you. I would certainly not have dared try to comfort you. I realize that your present misfortune, following so closely after the first one, will leave a wound bleeding for a long time.
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´ e´ particulierement ` Vous pourrez la communiquer a` ceux qui ont et mes amis a` Rome, tels que MM. Castelnuovo, Sella et Reina.167
But I would have liked to tell you how the fatal outcome of those wounds, which had seemed so minor to us, has profoundly upset us all. We knew your son for only a few hours; this brief time was sufficient for us to be attracted by this extraordinary child. I am happy that I knew him before he was wounded, before we could think about the possibility of losing him. My command post was very advanced; to get there, it was necessary to pass through a terribly destroyed area. This eighteen years old child was eager to do it in order to immediately present himself before his group chief. He arrived in front of me, as relaxed and as smiling as if he had passed through the park of Luxembourg. The next day he had to go to our advanced observation post. He had the same attitude, the same tranquillity and went to where duty called him, accompanied by a single soldier. I could not stop myself from telling it to all those who were around us. And when I saw him on his stretcher, with his two poor legs cut through by shell fragments, not complaining in spite of the pain, I felt real sorrow. And thinking of my oldest son, also a cadet, I caressed the cheek of your child and shall not forget the glance with which he followed me after this caress. I immediately promised myself to obtain for him the croix de guerre, not as payment for the blood that was shed and the wound which I believed slight, but because of his bearing. The same day I asked that it should be granted to him with the golden star of the Corps d’Arme. The regiment commander had warmly supported my request. Unfortunately the sacrifice he had made for his country turned out to be much more serious than we had believed; the reward we had proposed seemed insufficient and, with urgency, the Army awarded him the soldiers highest award, the military medal and the Croix de guerre with palm. I feel compassion for you, Sir, for the immense loss you have sustained; I wish there was some means by which your sorrow might be alleviated. I can only say to you that this child was admirable, that his eyes showed an uncommon intelligence, that his attitude in the face of danger revealed an extraordinary soul, that his conversation, in which the names of his father and mother were constantly on his lips while he was cared for, revealed a heart of gold, and that there was no reference to the pain he was suffering because of his wound. I received your letter a few minutes before taking a train to go back to my post, after my six days of rest; my answer probably suffers from my haste to answer you. You will have the kindness to excuse me. I send you, Sir, the assurance of my most profound and genuine sympathy. Commandant Pommier
167
Alfonso Sella (1865–1907) was professor of physics at the University of Rome and had a relevant role – together with Volterra and Pietro Blaserna – in the foundation of the Societ`a Italiana per il Progresso delle Scienze of which he was the director. He was one of the first scientists who studied the radium in Italy. Vincenzo Reina (1862–1919) graduated in mathematics from the University of Pavia in 1885 and became assistant professor of geodesy in Rome in 1887. In 1891 he was appointed professor of geodesy at the School for Engineers (Istituto Politecnico) in Rome.
92
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Transmettez, je vous prie, mes respectueux remerciements a` Madame Volterra et croyez moi ´ Votre bien cordialement devou e´ J. Hadamard
Picard to Volterra Paris, 1 August 1916 Cher ami, ´ e´ tres ` heureux d’avoir de vos nouvelles. Je crois qu’une de vos J’ai et ˆ lettres a duˆ etre perdue, car je n’avais pas rec¸u votre avis que le Comite´ ´ International de Louvain (en ce qui concerne les membres Italiens) etait ´ ´ J’en suis tres ` heureux, et je ne doute pas que la definitivement constitue. ` aisement. ´ formation du Comite´ Italien se fasse aussi tres ˆ a` parler d’autres questions d’un Il est probable que nous aurons bientot ` plus etendu. ´ caractere Vous savez qu’il y a en France un Comite´ du Livre;168 ˆ vous avez meme, je crois, un peu assiste´ a` Rome a` sa naissance, notre ´ ´ M. Maspero170 occupes. Ambassadeur et M. Tondeur-Scheffler169 s’en etant ´ ´ ´ Le Conseil m’a nomme´ a` sa place samedi etait le President du Comite. ´ dernier, et je compte m’occuper activement de cette affaire, qui doit acquerir ´ une grande importance en resserrant les liens intellectuels entre les Allies. ˆ ´ ˆ parallele, ` L’Association dont vous etes le President en Italie va jouer un role ˆ et je ne doute pas que nous ne marchions la main dans la main. La tache est ´ ´ ´ enorme, l’emprise Allemande etant si forte depuis tant d’annees. Je ne vous cache pas que pour ma part (et je ne suis pas le seul), je crois que les rela´ tions intellectuelles avec les Allemands doivent, pendant bien des annees, ˆ ` completement ` ´ etre a` peu pres supprimees. Autrement, nous retomberons ˆ sous le joug. Je sais que je n’irais pas a` un Congres ` International bientot ou` je rencontrerais des Allemands∗ ;171 je crois que plusieurs groupements ` International des internationaux devront se scinder en deux, tels le Congres 168
This Committee was founded by Gaston Maspero in May 1916 with the aim of developing French culture abroad. See ♥ 9.
169
Alfred Tondeur-Scheffler (1873–?) was a French diplomat. In 1912 he was vice-consul in Poland and then in Rome (from 1914). He became consul in 1920 and officer of the L´egion d’Honneur in 1923. For his participation in the foundation of the Comit´e du Livre See ♥ 9.
170 171
Gaston Maspero (1846–1916) died in June 1916. On him, see ♥ 9.
The first International Congress of Mathematicians after the War was held in 1920 in Strasbourg and German mathematicians were excluded. The following Congress was in Toronto in 1924; only in 1928 (Congress of Bologna) international relations between mathematicians went back to normal.
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´ ´ Mathematiciens et l’Association Internationale des Academies. L’Allemagne ´ par sa barbarie, et je vois avec plaisir s’est mise en dehors des pays civilises ´ trouvait echo ´ que cette pensee hier au Parlement Britannique. Je me permets de vous envoyer un article que j’ai fait a` ce sujet dans “Le Figaro”;172 j’y joins un article de la Revue des Deux-Mondes du 1er Juillet 1915.173 Nous reparlerons de tout cela plus longuement dans les mois qui vont venir, la ´ guerre, helas !, devant certainement encore durer longtemps, un an environ, a` mon estimation d’ailleurs toute personnelle. ` Mon systeme nerveux se remet peu a` peu, et je me trouve beaucoup mieux qu’il y a quelques mois, les crises nerveuses allant en s’espac¸ant. ´ J’avais pris les mathematiques en horreur; maintenant je commence a` me ´ ere ` m’occuper de choses remettre au travail scientifique, quoique je pref ´ eral. ´ d’ordre plus gen J’avais appris que vous vous occupez avec ardeur des questions d’aviation. ´ ` comme Je vous en felicite vivement; votre esprit si vif et si profond peut la, ailleurs, rendre les plus grands services. Il faut que chacun, qui ne peut ` ou d’une autre. porter les armes, serve la patrie d’une maniere ` ´ d’aller J’allais oublie´ de vous dire que j’approuve completement votre idee chercher le noyau du Comite´ Italien pour Louvain dans votre Association ´ pour l’entente intellectuelle. La chose est toute indiquee. Je vais quitter Paris pour trois semaines environ, pour rejoindre mes ´ petits-fils au bord de la mer; les lettres m’y arriveront sans difficultes! Veuillez, cher ami, nous rappeler, ma femme et moi, au souvenir de M.me Volterra, et croire a` mes sentiments de vive affection, Emile Picard ∗ ´ Il y a quelques mois, j’ai, par l’intermediaire de l’Ambassade d’Espagne `a Berne, envoye´ ma demission ´ ´ de membre correspondant de l’Academie ´ ´ ¨ des Sciences de Berlin et de la Societe Royale de Gottingen. Vous savez
172
The biologist Gabriel Petit and the journalist Maurice Leudet (from the newspaper Le Figaro) decided to answer to the German manifest to the intellectuals (see footnote 27) by collecting the opinions of several famous French scientists about German science. As may be expected, Picard enthusiastically accepted to participate to this initiative. The articles obtained by Petit and Leudet were published in Le Figaro since April 1915, and subsequently collected in the book Les Allemands et la Science published in 1916 by F. Alcan, with a preface by Deschanel, then president of the Chamber of Deputies. The articles in general adopt an utterly negative tonality to comment on German science. Interestingly, Picard concludes his own intervention by mentioning the future necessity of a thorough revision of the organization of the international congresses, which will be his obsession at the end of the war (see below the letters of the after-war period).
173 The volume 28 (July 1915) of the journal Revue des deux mondes contains the paper of Picard, L’histoire des sciences et les pr´etentions de la science allemande (pp. 55–79).
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ sigque nous avons raye´ de nos listes les Correspondants et les Associes nataires de l’odieux Manifeste.174 .
Hadamard to Volterra Paris, n.d.175 Mon cher ami, ´ que vous avez si aimablement Mon neveu le lieut.t Jacques Debre, ` accueilli en 1908, a rec¸u comme tous ses collegues une circulaire faisant appel aux officiers qui parlent italien: il s’est inscrit. Si je tiens a` vous en informer, c’est parce que je crains un peu que, comme il arrive pour beaucoup de circulaires demandant des aptitudes ´ ´ speciales, les nominations qu’en resultent ne tombent pas toujours sur ceux ´ ´ ´ qui sont specialement design es. C’est aussi parce que je sais quels services il peut rendre. Sans parler de sa connaissance – vous vous rappelez sans doute combien elle est par´ erale ´ faite – de la langue italienne, il a une intelligence gen remarquable: ´ ´ a, ` au moment de la guerre, un de nos ingenieurs ´ ´ Il se c’etait dej distingues. ´ trouve d’autre part que partant au debut de la guerre dans le 75, il a du, ˆ ˆ ` avoir pris depuis sa blessure, etre incorpore´ dans l’artillerie lourde, apres ´ part a` des nombreuses experiences pendant sa convalescence, de sorte qu’il est au courant de l’ensemble de l’artillerie. ´ vous paraˆıt de nature a` vous le faire Je ne sais si cet ensemble de qualites ´ ´ ´ italienne. Dans le cas ou` vous le desirer pour une cooperation avec l’armee penseriez il y aurait lieu, me semble-t-il, d’insister en le demandant; car Dieu sait ce qui peut se passer dans les bureaux de tous les pays du monde et ´ pour les services que vous pourriez recevoir de beaucoup moins qualifie, vous avez a` en attendre, fut-ce au point de vue de la connaissance de votre ˆ langue. Il ne faut pas non plus que j’oublie de vous rappeler – car cela a son ´ – que sa importance lorsqu’il s’agit d’attirer des officiers des nations alliees superbe conduite lui a valu, depuis la Marne, non seulement la Croix de ´ guerre, mais la Legion d’Honneur.
174
The question of excluding German corresponding members of the Paris Academy of Science resulted in harsh debates where Picard, as may be expected, had supported the most severe line. A secret committee met at the Academy on 15 March 1915, the same day when the decease of the German physicist Hittorff (1824–1914), corresponding member of Paris Academy of Sciences, was (probably on purpose) officially announced to the Academy. For an analysis of this tumultuous secret committee, see Anne Rasmussen, “La science franc¸aise dans la guerre des manifestes, 1914–1918”, Mots. Les langages du politique, 76, Guerres et paix. D´ebats, combats, pol´emiques, novembre 2004 http://mots.revues.org/index1843.html 175
From the context, the letter may be dated from September or October 1916.
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´ vers la Dobroudja Vous avez sans doute, comme nous, les yeux tournes ´ ˆ et etre et les Balkhans176 : Nous ne pouvons, vous et nous, que nous feliciter ´ fiers de ce que se passe sur nos propres fronts. Mais quelles repercussions ˆ ´ enements ` ne peuvent pas avoir, meme sur ces fronts, les ev orientaux. ´ Presentez, je vous prie, nos respects a` Madame Volterra et croyez moi ´ Votre bien cordialement devou e´ J. Hadamard
Borel to Volterra Paris177 , 1 October 1916 Mon cher ami, ´ Voila` bien lontemps que je ne vous ai pas ecrit ; ce n’est pas que je n’aie pense´ souvent a` vous. Chaque fois que l’Italie affermissait davantage sa ` militaires etaient ´ politique anti-allemande, chaque fois que ses succes un ´ ´ ma pensee ´ se reportait sur les Italiens, qui ont reconfort pour tous les allies, ´ e´ amis de la France, et sur vous en particulier. toujours et J’ai su par Hadamard que vous vous occupiez activement de questions techniques importantes; comme vous le savez sans doute, M.Painleve´ m’a ` des Inventions; apres ` demande´ de l’aider a` organiser son nouveau ministere moins d’un an, je crois que nous avons fait une œuvre assez utile. Nous 178 ` etroites. ´ . avons en particulier, organise´ avec l’Angleterre des relations tres 176
sic. Hadamard probably refers to the Romanian decision to enter the war on the side of the Entente. Interestingly, the situation of Romania had some similarity with Italy. A secret agreement signed in 1883 linked the country with the Central Empires. As it had been the case for Italy, Romania proclaimed its neutrality on 3 August 1914 explaining that the war was initiated by Austria. During the year 1915, the Prime Minister Bratianu came together with the Entente, and on 28 August, Romania entered the war. They were soon confronted by Bulgarian troops in the Dobrogea, and severely defeated by the German and Austro-Hungarian armies. On 6 December 1916, General August von Mackensen (1849–1945), who directed the German offensive in the Dobrogea since October, moved into Bucharest.
177
Envelope and letterhead of the Office of the Minister of Public Instruction (see footnote 105). The letter was forwarded (probably by Virginia Volterra) to Cantiere Dirigibili, Pontedera (construction site of dirigibles, Pontedera).
178
As already mentioned, Borel was called by Painlev´e on November 1915 to organize the new Direction des Inventions (see an interesting document in [26], p. 96). Borel created several sections, devoted to special missions, such as the chemical production or the ballistic questions. A section was specially devoted to the question of the relations with the allied countries. It included representatives from Great-Britain, Belgium, Italy and above all Russia; a directory found in the Archives Volterra indicates the following list: Sir Henry Norman and Cap. Goldschmidt (Britain), Lieutenant G´erard (Belgium), Professeur Giordano (Italy), and 7 persons for Russia, namely Colonel Antonoff, Colonel Svidersey, Colonel Davidoff, Capitaine de Fr´egate Pachkoff, Lieutenant de Vais-
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ ´ 179 ; sur notre invitation, Nos relations avec l’Italie sont moins developp ees ´ votre pays est cependant represent e´ a` notre Comite´ interallie´ des inven´ egu ´ e´ de votre gouvernement, prend une part tions et M.Giordano,180 del active et fructueuse a` nos travaux. Pour resserrer encore cette collaboration, M.Painleve´ m’a demande´ de faire prochainement un voyage en Italie ˆ (il y viendrait d’ailleurs volontiers lui-meme s’il en avait la possibilite´ ; mais il ´ ˆ n’ose s’y engager, car sa presence peut etre indispensable aux conseils du
seau Liphardt, Lieutenant de Vaisseau Djevertzki [sic] and Colonel Oulianine (Russie). It would certainly be interesting to have further studies on what became of the Russian delegates after 1917. Some information about the links between Painlev´e and the Russian school of engineering can be found in Claudine Fontanon : Paul Painlev´e et la mobilisation des math´ematiciens russes autour de la premi`ere guerre mondiale in [22] . In fact, we had difficulties to locate archival material about this Comit´e of the Direction des Inventions. It may have had more a formal and limited activity than a real intervention in the work of the Direction. About the Italian delegate Federico Giordano, see footnote 180. 179
For a general overview about the relations between the French and the Italian armies during WW1, consult Filippo Cappellano, “Les relations entre les arm´ees italienne et franc¸aise pendant la Grande Guerre”, Revue historique des arm´ees, 250, 2008 (http://rha.revues.org//index182.html).
180
On 19 July 1915, Federico (or Federigo) Giordano, a professor of engineering who had been involved in research about the mechanization of agriculture, and some of his colleagues of the Polytechnic Institute of Milan founded the “Comitato Nazionale Esami invenzioni attinenti al materiale di guerra” which represented Italy in the “Comit´e interalli´es des Inventions” (see footnote 178). The Committee examined more than 4000 inventions related to war material, of which 200 were selected and proposed, with some improvements, to the authorities of Army and Navy. Giordano may have been somewhat territorial about his prerogatives, as in subsequent letters, Borel comments on managing Giordano’s sensitivities in order to facilitate common projects with Volterra (see Borel’s letter from June 1st, 1918 and the following ones). A possible reason for Giordano’s attitude could be the foundation by Volterra of another institution similar to his Comitato. Indeed, between the end of 1916 and the beginning of 1917, the Office for Inventions and Research (Ufficio Invenzioni e Ricerche) was created on the French model. We quote a letter (27 February 1917) from the Under-Secretary of Arms and Munitions to the Minister of War (Cartella VI Volterra’s Archive, Accademia dei Lincei): “In a personal letter of 2 November of this year [1916], his Excellency the Minister of Public Education, drew the attention of Your Excellency to the advisability, pointed out to him by Mr. Emile Borel, Head of Cabinet of the French Ministry of Inventions, to send there an Italian Professor who could study how the scientific institutes and laboratories of the university are associated with the military administration as regards inventions, and proposed to entrust the task to Senator, Professor Volterra. Consenting to this proposal, Your Excellency entrusted the specific task to the Professor Volterra, who, when his mission was concluded, directed to Your Excellency a detailed report on the French organization of everything which has to do with national defense, concluding with the advisability to mobilize even in Italy the scientific forces of the country and to make use of the not negligible resources of numerous scientific institutes, which would relieve the burden of the military technical plants and offices. Agreeing with this advisability, Your Excellency invited Professor Volterra to draw up a project which specified the aims and competence of the new Office which would have to be created with this purpose, and which indicated on which public and private institutes it might rely for scientific or experimental assistance. In consequence, Professor Volterra presented to Your Excellency a detailed project for the new Central Office.” See further details in [46, 24] .
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gouvernement) ; j’ai parle´ de ce projet a` M.Giordano, qui a bien voulu me ` satisfait de ce voyage et qu’il se chargerait d’en organiser dire qu’il serait tres ` qu’il remplisse au mieux notre but commun. M. le programme, de maniere Giordano est en ce moment en Italie; je l’ai charge´ de mon meilleur souvenir pour vous, s’il peut vous voir; il doit revenir a` Paris du 10 au 17 octobre pour ´ ´ c’est vers le 17 ou le 18 que je partirais les reunions du Comite´ interallie; avec lui pour l’Italie. Je n’ai pas besoin de vous dire que, pour bien des raisons, je tiendrais beaucoup a` vous voir et a` causer longuement avec vous, ´ si cela peut se faire sans vous deranger. ´ Veuillez presenter mes respectueux hommages et les souvenirs de ma femme a` Madame Volterra et accepter l’expression de ma plus cordiale ´ amitie. Emile Borel
Volterra to Borel Pontedera (Aeroscalo Dirigibili)181 , 10 October 1916 Mon cher Ami, J’ai appris par votre lettre que vous viendrez sous peu en Italie et, il y a peu de jours, M. Giordano182 m’a fait part que vous serez en Italie a` peu ` le 20 courant. Je suis heureux de cette bonne nouvelle et je vous prie pres ´ et l’itineraire ´ de vouloir bien m’annoncer le jour de votre arrivee que vous ´ ´ desirez suivre dans le voyage. Desirez-vous venir directement a` Rome, ou ´ ˆ desirez-vous vous arreter d’abord dans le Nord d’Italie? ´ e´ tres ` occupe´ depuis le commencement de la guerre dans les nouJ’ai et ´ ` avoir et ´ e´ velles constructions aeronautiques et je suis maintenant ici apres un peu partout pour essayer les nouveaux appareils. Mais je pense que dans la seconde moitie´ du mois courant j’aurai quelques jours de repos et je serai heureux de pouvoir me trouver avec vous et vous ˆ accompagner dans votre visite et de vous etre utile et de faciliter votre voyage. Je n’ai pas besoin de vous dire que je pense bien souvent a` vous et ´ e´ heureux chaque fois que j’ai rec¸u de vos nouvelles. Tout ce qui que j’ai et ` bien. Vous verrez que l’esprit de nos se rapporte a` la guerre marche tres ` elev ´ e. ´ Nous sommes surs soldats et de notre peuple est tres ˆ de la victoire ´ et la patience et l’ardeur ne nous manquent pas. avec nos allies
181
See footnote 177.
182
See footnote 180.
98
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Nous qui avons voulu avec toute la fermete´ et toute la confiance la guerre ˆ e´ de la France et ses allies ´ nous pouvons constater avec joie que toutes a` cot ´ ´ nos previsions se verifient. ´ Veuillez bien m’ecrire en dirigeant votre lettre a` mon adresse a` Rome ´ ou` je me trouverai entre deux et trois jours. Veuillez bien presenter mes hommages a` Madame Borel et veuillez accepter, mon cher Ami, l’expression ´ de toute mon affection et de tout mon devouement. Vito Volterra
Hadamard to Volterra Paris, 21 October 1916 ` Ministere de l’Instruction Publique, des Beaux-Arts ´ et des Inventions interessant ´ la Defense Nationale Direction des Inventions Mon cher ami, Je profite de la venue de M. de Broglie183 pour vous envoyer un mot. Vous ´ ne serez pas trop etonn e´ de voir que ce mot ne contient rien, si ce n’est que ´ nous vivons. Je n’ai rien d’autre a` dire de nous, a` present. ´ Presentez, je vous prie, nos respects a` Madame Volterra et croyez moi ´ Votre tristement devou e´ J. Hadamard ´ e´ Gauthier Villars vous a envoye´ le 2 juin dernier le fascicule de la Societ ´ ` que vous Mathematique (fascicule 1 de 1915) qui vous manquait. J’espere l’avez bien rec¸u.
183
Louis Victor de Broglie (1892–1987), French physicist, won the Nobel Prize in Physics in 1929 for his research on wave mechanics. He developed the wave-particle duality theory of matter, based on the work of Einstein and Planck. With the outbreak of WW1 in 1914, he offered his services to the army for developing radio communications.
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Hadamard to Volterra Paris, n.d. [November 1916?] Cher ami, ˆ si je n’avais eu quelque peu de grippe. Je vous aurais envoye´ ceci plus tot Je viens de causer avec la Ligue ; ils vont se joindre a` la protestation socialiste dont je vous parlais et collectivement pour les calomnies a` soumettre au Ministre.184 ´ ephone ´ N’en ferez vous pas autant? Je vous en reparlerai par tel ou autrement. Bien cordialement J. H.
Borel to Volterra Paris, 7 November 1916 Mon cher ami, ´ ´ Je suis habituelleJe me rejouis beaucoup de votre prochaine arrivee. ´ a` l’Ecole Normale (Tel ´ ephone ´ ment dans la matinee Gobelins 06-45) et ` ´ ephone ´ l’apres-midi 23 bis rue de l’Universite´ (Tel Fleurus 05-71).185
184
The meaning of the present sentence is very unclear, and our transcription of the very bad handwriting in this note is doubtful. An hypothesis may however be proposed, related to the important conference of the Ligue des droits de l’homme held in Paris on 1 and 2 November 1916 at the Mus´ee Social located at the 5, rue Las Cases (where it is still located today). The stenographic transcription of this conference is accessible on Gallica (NUMM- 109923). The Ligue des droits de l’homme has been founded in 1898 in Paris as a reaction against the Dreyfus’ affair by the senator Ludovic Trarieux (1840–1904). Hadamard participated in the activities of the Ligue; in the Bulletin officiel de la Ligue des droits de l’homme, 1916, p. 470 (meeting dated July 17, 1916) one can read: “M. Jacques Hadamard, who recently faced a cruel mourning (see B. O., p. 462)) has just lost a second son on the battle field. The Central Committee, deeply moved, asks the General secretary to transmit its most warm sympathy to M. Hadamard.” According to the transcription, Hadamard was present as delegate at the conference of November. During the event, the delicate matter of “the conditions for a long peace” – based on justice and on the achievement of the so-called “Soci´et´e des Nations” was discussed, and the transcription reveals harsh exchanges (see pp. 217 et seq.). In particular, the submission of a motion by the federation of Paris attracted vigorous protests. Hadamard may refer to this problem in the present letter. See also M.R. Mouton: L’id´ee d’organisation internationale en France et en Italie pendant la Premi`ere Guerre Mondiale, in [25], pp. 100–121.
185
The Sous-Secr´etariat d’Etat aux Inventions was located at the mentioned address.
100
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ Jeudi soir 9 novembre a lieu le banquet mensuel de l’Aero-Club de ˆ libre, je serais heureux de vous y amener, car ce France.186 Si vous etes ´ ´ serait une occasion de vous presenter a` diverses personnes s’interessant aux dirigeables. ´ ´ Votre bien devou e, Emile Borel
Picard to Volterra Paris, 21 November 1916 Cher ami, Pour le cas ou` je n’aurais pas le plaisir de vous rencontrer tout a` l’heure, je vous transmets la liste que je retrouve. J’ai apporte´ seulement les noms ´ de Boselli, Millosevich et Pigorini, qui n’y etaient pas, mais qui vous m’aviez indique´ hier ´ ´ du Conseil Meda, deput e´ (ministre, je crois)188 Luzzati,187 ancien President 189 Villari – Florence Arrigo-Bo¨ıto190 – Milan compositeurs 191 ´ – Rome Leoncavallo ´ Marconi – Senateur – Rome Monteverde – Critique d’Art – Rome Ricci – Directeur g.al Beaux Arts – Rome ´ Pise Tonolo192 – Professeur a` l’Universite, Rigi193 – id., Bologne ` Venturi194 – id., Modene Ruffini – Ministre Instr. Publique, Turin195 186 The A´ero-Club de France was created in 1898. It was the first club in the world devoted to the promotion of travels by air. 187
sic; the real name is Luzzatti. See note 137.
188
He was Minister of Finance. See note 118.
189
Pasquale Villari (1826–1917) was a historian and politician, professor of history at the University of Pisa. He was Senator (from 1884 onwards) and then Minister of Public Education in 1891 with Di Rudin`ı’s government.
190
sic.
191
sic.
192
sic. In fact, Toniolo.
193
sic. In fact, Righi.
194
Adolfo Venturi (1856–1941) was an Italian art historian. His main project concerns the great History of Italian Art (Storia dell’arte italiana) in many volumes which unfortunately stopped at the 16th century.
195
See footnote 120. Ruffini became minister on June 1916.
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´ Milan Beltrami Prof. a` l’Universite, ´ Boselli – President du Conseil ´ Volterra – Senateur – Rome ´ Millosevich – Secretaire Ac. Lincei (Sc. Ph.) Pigorini – id. (Sc. Mor.) Puis-je donner cette liste a` M. Imbart de la Tour? Il s’agit, bien entendu, ` de Louvain. du Comite´ International pour la reconstitution de la Bibliotheque Bien affectueusement, Emile Picard ´ le maximum pour l’Italie. Il y a M. Imbart de la Tour avait pense´ que 16 etait ´ ´ 17 noms sur la liste. Si il etait necessaire d’en retirer un, quel est celui que vous proposeriez.
Picard to Volterra Paris, 8 February 1917 Cher ami, ´ Je suis impardonnable de ne pas avoir encore repondu a` votre aimable ´ J’ai et ´ e´ assez souffrant d’une sinusite tres ` douloureuse, lettre du 30 Dec. ´ que les froids epouvantables que nous subissons n’ont pas contribue´ a` ´ guerir. ´ e´ sans doute tres ` impressionnes, ´ comme nous, par la tenVous avez et sion entre l’Allemagne et les Etats-Unis. Quoi qu’il arrive, l’effet moral restera ` grand, et bientot ˆ l’Allemagne et ses allies ´ auront contre eux, au moins tres moralement, tout l’univers.196 ˆ Je pense que M. Imbart de la Tour vous a demande´ lui-meme la liste ´ ` definitive Italienne pour le Comite´ (international) de la bibliotheque de Lou´ ´ Vous aurez sans doute vain. Je vous avais adresse´ a` Paris la liste presum ee. retrouve´ tous les noms; je vous suis oblige´ de me donner aussi cette liste ´ definitive. ´ La creation a` Paris d’une Ecole analogue a` celle que nous avons a` Rome ´ et. ˆ Nous travaillons activement au Comite´ du Livre serait du plus haut inter en ce moment a` la question des catalogues;197 on ne saurait attacher trop 196
Worried by the German intransigeance and the weakening of the Allies, the USA broke their diplomatic relations with Germany on 3 February 1917, and the events pushed them inexorably along the road to war. Wilson made the decision to declare war on Germany on 20 March 1917 and the decision was approved by Congress at the beginning of April.
197 On the Comit´e du Livre, see ♥ 9 and ♥ 10. The Comit´e was founded in 1916 by Gaston Maspero and Picard and Volterra were strongly involved in it. The aim was to reinforce the relations between Italy and France. Here Picard refers to the Ecole franc¸aise de Rome (Palazzo Farnese) or
102
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
d’importance, en tout pays, a` la proscription des livres pornographiques que ´ ´ ´ l’Allemagne deverse en differentes langues et represente comme des productions Franc¸aises, Italiennes, etc. . . ; ce qui permet a` la vertueuse Germanie de se voiler la face. ´ nous rapprocher du but vers lequel tendent les peuPuisse cette annee ´ Nous avons encore de grands efforts a` faire, mais le resultat ´ ples civilises. ` de l’Allemagne se n’est pas douteux. Je ne crois pas que la barbarie fonciere ` ˆ repente jamais sincerement et se modifie essentiellement; elle est la meme ` au fond depuis trop de siecles. Mais il faut qu’elle soit incapable de nuire ` pendant au moins un sie` ecle. ´ Veuillez, cher ami, presenter a` Madame Volterra votre respectueux sou´ venir, et croire a` mes sentiments de vieille amitie, Emile Picard
Picard to Volterra Paris, 17 April 1917 Cher ami, ` ´ Le Comite´ de la Bibliotheque de Louvain se reunit aujourd’hui a` l’Institut ` heureux, si vous pouviez y venir. Nous allons discuter la a` 4h . On serait tres ´ redaction de l’appel international et la date du lancement. ´ internationaux sont constitues, ´ sauf l’Italie. PourriezTous les comites ˆ les noms de la fameuse liste que je vous avais vous nous donner bientot ´ et dont malheureusement, M. Imbart de la Tour et moi, nous envoyee, ´ a` eu d’ailleurs cette liste entre n’avons pas garde´ copie? Vous aviez dej les mains, et il ne s’agissent que de deux ou trois additions. Il serait bien ˆ a` l’appel. La liste, que vous donnerez, peut ennuyeux que l’Italie manquat ˆ ´ ´ e´ perdue; c’est vous qui etes ˆ d’ailleurs etre differente de celle qui a et le meilleur juge pour les noms d’Italie. ` donc vous voir cet apres-midi. ` J’espere Vous me trouverez a` 4h . a` l’Institut dans mon cabinet. Bien affectueusement, Emile Picard to the Acad´emie de France of Rome (Villa Medici). Moreover, in his Report on the activity of the Committee (February 1918), Jacques de Dampierre (who succeeded to Maspero as President of the Comit´e du Livre at Summer 1916) pointed out that an important aim was to found in Paris an Italian institute similar to these French institutions in Rome. In the same document, J. de Dampierre referred also to the problem of Bibliography and Catalogue (Archives Nationales, Paris, Dampierre 289AP.32); see ♥ 9.
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Borel to Volterra Paris198 , 15 June 1917 Mon cher ami, ´ e´ heureux de voir M.Abetti199 qui va partir pour rejoindre la mission J’ai et ´ J’espere ` qu’il vous sera possible d’aller aussi aux Etats-Unis et interalliee. que ce sera pour moi une occasion de vous revoir ici a` votre passage! La ´ ´ est une nouvelle manifesrealisation de cette mission scientifique interalliee ´ ´ tation de l’accord que nous desirons tous et qui est necessaire a` la victoire. ´ Votre bien affectueusement devou e´ Emile Borel
Borel to Volterra Paris200 , 14 July [1917] Mon cher ami, M. Painleve´ me prie de vous demander de venir a` 4h1/2 au lieu de 4h. ´ Votre bien devou e´ Emile Borel
198
Card with the letterhead of the Ministry of War.
199
Giorgio Abetti (1882–1892) was born in Padova to the noted Italian astronomer Antonio Abetti. He also became an astronomer and is known for having led expeditions to Sudan and Siberia for observing solar eclipses. In 1917, he was sent as an Italian delegate to the inter-Allied mission in Washington. There he was in touch with the American astronomer George Ellery Hale, founder of Mount Wilson Observatory. Later, when he became director of the Arcetri Observatory in Italy, he organized the building of the first tower for solar observation in Italy, inspired by the tower built by Hale at Mont Wilson.
200
Postcard with headings of the Minist`ere de la Guerre. The envelope is addressed to M. le S´enateur Volterra, Hˆotel Lutetia, Boulevard Raspail. The Hotel Lutetia is one of the most famous hotels in Paris, located at the corner of Boulevard Raspail and Rue de S`evres, near Saint-Germain des Pr´es. Its famous Art Nouveau style building has often been a place of official ceremonies.
104
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Borel to Volterra Paris201 , 19 August 1917 Mon cher ami, Voici plusieurs semaines que je suis sans nouvelles de vous; vous ´ ` m’aviez laisse´ esperer que vous reviendriez a` Paris au mois d’aout; ˆ j’espere ´ mais seulement differ ´ e. ´ que votre projet n’est pas abandonne, ´ italienne ont eu aussi ´ Les appareils de reperage C.W.202 pour l’armee ´ a` expedi ´ ee ´ et le restant ne tardera quelque retard, mais une partie est dej ´ pour la mise au point definitive ´ pas. il y a eu quelques difficultes des cap´ ` tout a` fait satteurs selectifs, mais maintenant cela marche d’une maniere isfaisante. Le lieutenant Danjon203 qui a commande´ pendant 18 mois une ´ ´ e´ design ´ section de reperage en Champagne, a et e´ pour aller en Italie. Il est ´ ´ ´ a` alle´ voir le Colonel de Saintignon204 pour preparer son depart. dej ´ Je voudrais pouvoir vous annoncer aussi le depart prochain du Ministre, ´ e´ mais malheureusement il ne fait pas toujours ce qu’il veut. Il avait esper ´ e´ empech ˆ e´ au dernier ´ 205 mais il en a et pouvoir accompagner M.Poincare, ˆ moment. Il vaut peut-etre mieux d’ailleurs que nous pensions ce voyage ` independante. ´ ´ d’une maniere La periode que j’aperc¸ois comme possible
201
Paper with headings of Minist`ere de la Guerre. Cabinet du Ministre. Services Techniques.
202
See footnote 204.
203
Andr´e-Louis Danjon (1890–1967) was a French astronomer born in Caen. He devised a method to measure the “Earthshine” on the Moon. His measures are now known as the Danjon Scale. Danjon came to Italy in the subsequent weeks and remained there during the first semester of 1918, in order to help organizing a section of gun localization by sound on the Italian Front. Volterra was very active in helping him, and Volterra’s archives contain many letters from Danjon. The situation seems to have been delicate for him during the first months, both because of Caporetto disaster and of the Italian mistrust towards the French soldiers. Moreover, the necessary equipments were sent from Paris with a great delay (this is evoked in Volterra’s subsequent exchanges with Borel). At the end of 1917, the desperate Danjon wanted to go back to France. However, it seems that the situation gradually improved, and at the end of his Italian period, Danjon wrote to Volterra that thanks to him and his Italian collaborators, he had been able to make an excellent job. The correspondence between Danjon and Volterra went on after WW1. On Danjon and the military technical exchanges between France and Italy, see Martina Schiavon: The Special detection in France and in Italy during the First World War, to appear. 204 205
The name is badly written and we could not crosscheck the information.
In August 1917, Painlev´e was still minister of war before becoming on 12 September the new Prime Minister (see footnote 218). One may observe in Borel and Volterra’s exchanges of this precise moments how the question of the journey to Rome of French officials had taken a particular importance. This may have a connection with the question of a separate peace with Austria which had been a matter of hectic debates in France since March 1917. On this question, see S. de Bourbon: L’offre de paix s´epar´ee de l’Autriche, Plon, 1920.
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´ des chambres206 ); peut-etre ˆ est du 8 au 18 septembre (date de la rentree ` etait ´ ´ pourrait-on prolonger jusqu’au 20 si une raison particuliere donnee ˆ ` Je vais faire tous mes efforts pour lever tous les d’etre a` Rome ce jour-la. ˆ ˆ e´ en ecrivant ´ obstacles; peut-etre pourriez-vous m’y aider de votre cot a` M. ´ soit directement, soit par mon intermediaire, ´ Painleve, dans le cas ou` vous ´ jugeriez qu’un voyage dans cette periode serait opportun et bien accueilli chez vous. ´ Veuillez presenter mes hommages a` Madame Volterra et me croire tou´ ´ jours votre affectueusement devou e. Emile Borel
Volterra to Borel Rome, 25 August 1917 ` reserv ´ ´ Tres ee Mon cher Ami, ´ ˆ c’est qu’il m’a fallu attendre la rentree ´ Si je ne vous ai pas ecrit plus tot de nos ministres pour vous donner des nouvelles se rapportant au voyage ´ de Monsieur Painleve. ´ ´ J’ai eu deux conferences avec le president du Conseil et aujourd’hui j’ai parle´ avec Monsieur Sonnino.207 ´ Voici le resultat de mes pourparlers que je vous prie de vouloir bien porter ` tout a` fait confia` connaissance de M.Painleve´ bien entendu d’une maniere dentielle: 1) Le voyage de Monsieur Painleve´ est accueilli avec le plus vif plaisir ` utile et pourra avoir une grande par nos ministres et on pense qu’il sera tres importance. 2) Je n’ai pas besoin de vous dire que Monsieur S[onnino]. a rec¸u une ` grande impression en voyant Monsieur Painleve´ et en parlant avec lui tres 206
The parliamentary life in France during the war, though not frequently mentioned, was very vivid, except at the very beginning of the war between August and December 1914 when the Parliament remained closed. Deputies obstinately tried to keep some control over military operations. On the subject, consult J.B. Duroselle: La Grande guerre des Franc¸ais, Perrin, 1994, Chapter 7.
207
Sidney Costantino Sonnino (1847–1922) was one of the major personalities in Italian politics during the war. Sonnino was born to an Italian father with Jewish origins and a Welsh mother and appears as a typical 19th century politician. Nevertheless, he had several original features: Protestant in an almost uniformly Catholic country, he was an intellectual, a specialist on Dante’s work. Though he was clearly in favour of the Central Empires in 1914, he was the major architect of the reversal of alliance in 1915 because he believed Britain and France more likely to let Italy obtain the irredente lands. On Sonnino, see for example [38], Chapter 22. .
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ ´ tout recemment. Il a pour lui la plus grande consideration et il comprend ˆ qu’il a et qu’il aura dans la politique. C’est pourquoi il desire ´ tout le role que son voyage en Italie non seulement ne passe pas inaperc¸u mais qu’il ait beaucoup de retentissement. ´ e´ arret ˆ e´ que le president ´ 3) Or M. Sonnino m’a dit qu’il a et du Conseil et ˆ bien probablement lui-meme vient a` Paris entre le 10 et le 16 Septembre et ˆ ´ les ministres Anglais iront aussi et a` la meme epoque le Roi rendra la visite ´ au President en France.208 . ´ 4) C’est pourquoi l’epoque du voyage entre le 8 Septembre et le 18 Septembre ne serait pas bien choisie parce que Monsieur Painleve´ ne pourrait pas voir nos ministres a` Rome, ni le Roi au front. En outre, le voyage ´ et ˆ qu’il merite ´ ne serait pas suivi par le public avec tout l’inter a` cause des ´ enements ´ autres voyages et ev qui auraient lieu contemporainement. A mon avis pour que l’utilite´ en soit la plus grande possible il faut que ces voyages ` que les hommes politiques les plus ne soient pas contemporains de maniere ´ ´ ´ par deux importants soient reunis par ces visites et ne soient pas separ es ˆ visites qui ont lieu en meme temps dans les deux pays. ˆ 209 que l’attention du public est toujours plus soutenue si Il pense meme ´ elles sont espacees. ˆ 5) Il serait bien donc que la visite ait lieu en Octobre. Tachez de faire tous vos efforts pour lever tous les obstacles. ` l’ouverture des chambres le 18 SeptemM. S[onnino]. pense que, apres ´ bre et une courte suite de seances on aura bien chez vous quelques jours d’interruption dans la session. Il suffit de peu de jours pour que le voyage ´ puisse avoir lieu selon le programme etabli (Front et Rome). 6) Par rapport a` un discours de M.Painleve´ a` Rome, Monsieur Sonnino ` content qu’il ait lieu. Il pense qu’il faut preparer ´ ´ serait tres une reunion pour ´ ´ cela. Il m’a demande´ quand a lieu la seance solennelle de l’Academie des ´ politiques. Mais cela serait trop tard Lincei ou` interviennent les autorites ´ ´ parce qu’elle a lieu au mois de Novembre. Faute de la reunion de l’Academie ` ´ on pourrait tres bien arranger en tout moment une reunion politique solen` intellectuel avec beaucoup de facilite´ (par nelle ayant aussi un caractere ´ exemple une reunion de l’entente intellectuelle)
208
After Austria had proposed a separate peace to France and Great-Britain, Paris and London had asked Vittorio Emanuele III to come to France. The journey eventually took place between 26 and 28 September and the king visited the Front together with Poincar´e. This visit is related in S. de Bourbon: L’offre de paix s´epar´ee de l’Autriche, Plon, 1920 (p. 302), and seems to have been kept secret as it was not commented on in newspapers. The indication Top secret at the beginning of Volterra’s letter corroborates the fact. 209
In the draft of this letter, in the previous sentence, Volterra wrote M. Sonnino pense que and not a` mon avis. When he copied the letter, Volterra had probably not completely corrected his draft, which results in a deficient syntax.
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Voila` ce que je me suis empresse´ de porter a` votre connaissance. Veuillez bien m’en donner votre avis et je le porterai tout de suite a` connaissance des Ministres. Je suis heureux que Monsieur Danjon210 vient en Italie et je vous en remercie beaucoup. J’en ai rec¸u aussi l’avis officiel de la part de Monsieur ´ eral. ´ de Saintignon211 et j’en ai averti le Grand Quartier Gen ˆ J’ai meme pense´ de me trouver avec lui au front et puisqu’il devait se ´ ´ egraphi ´ presenter a` Milan j’ai tel e´ au Commandant militaire de la Gare pour ´ ´ avoir de ses nouvelles. Mais je n’ai jusqu’a` present rec¸u de reponse. Je n’ai ´ pas rec¸u jusqu’a` present de nouvelles me rappelant a` Paris mais je n’ai pas besoin de vous dire que je serai toujours heureux de toute occasion qui se ´ presentera pour me rendre a` Paris. ´ Veuillez bien presenter mes sentiments les plus affectueux et les plus ´ ´ a` Monsieur Painleve´ et veuillez presenter ´ devou es tous mes hommages a` Madame Borel. ` et la plus Veuillez accepter l’expression de mon amitie´ la plus sincere ´ ´ et de toute mon estime et mon affection. devou ee Vito Volterra
Borel to Volterra Paris212 , 30 August 1917 Mon cher ami, J’ai communique´ votre lettre a` M.Painleve´ qui me charge de vous en remercier; il est tout a` fait d’accord avec vous et fera tous ses efforts pour ˆ libre au moment que vous indiquez. C’est seulement apres ` m’avoir parle´ etre ´ e´ informe´ des projets de vos ministres, auxquels il y a 15 jours qu’il avait et ´ les siens sont naturellement, en la circonstance, subordonnes. M. Danjon213 partira aujourd’hui ou demain; c’est seulement hier que le ´ que tous les papiers etaient ´ en Colonel de Saintignon214 nous a assures ` regle a` Milan. ´ l’expression de mes sentiments affectueusement devou ´ ´ Veuillez agreer es. Emile Borel 210
See footnote 203.
211
See footnote 204.
212
Postcard with letterhead of the Minist`ere de la Guerre.
213
See footnote 203.
214
See footnote 204.
108
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
ˆ Vous recevrez peut etre la visite de M.Albert Milhaud215 ; c’est un pro´ de Paris, que je connais bien, et qui a fait avec intelligence fesseur d’un lycee de la politique et du journalisme.
Volterra to Borel n.p., n.d.216 (a draft with many deletions) Mon cher Ami, ´ e´ heureux de voir ici il y a quelques jours M.Soumex [?] Il vous aura J’ai et rapporte´ certainement les propos que nous avons tenus [?] Pourriez-vous ´ le prier d’envoyer un petit rapport sur les experiences dont il nous a parle´ ´ en precisant l’espace libre qu’il faut disposer pour le planeur [?] ainsi que la ´ [?] dont il faut disposer pour l’actionner. fusee J’ai fait le mois passe´ une course pour voir M.Danjon et j’ai passe´ ` interess ´ quelques jours avec lui. Je me suis tres e´ a` la question a` la correction[?] du vent. ` de le revoir bientot, ˆ mais je suis tres ` occupe´ maintenant a` mon J’espere ´ erale ´ bureau. Monsieur Danjon a rencontre´ [?] la sympathie gen et je crois ´ que lui aussi est content de son sejour. ´ Croyez-vous que la proposition d’envoyer quelqu’un a` Toulon pour etudier ` appropriee ´ les belles recherches de M. Langevin et de poud’une maniere ´ ´ ˆ voir collaborer en Italie a` ces etudes par des experiences dans la meme
215
Albert Milhaud (1871–1955) was one of the main representatives of the French Parti RadicalSocialiste (of which Borel was to become deputy after 1924) – and one of its celebrated historians (see his Histoire du Radicalisme, Soci´et´e d’Editions Franc¸aises et Internationales, Paris, 1951). The first congress of the radical-socialist party since 1913 was held during Fall 1917, and Milhaud wrote the official conclusion of the congress works which insisted much on necessary educational reforms. This may explain why his friend Borel advised him to meet Volterra in Rome. At the beginning of 1917, Milhaud had also published a collection of some of his prewar (1912–1914) papers where he emphasized German militarism (La guerre qui venait, Boivin, Paris, 1917). We do not know whether the meeting with Volterra took place. 216
Probably September 1917. See footnote 218.
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orientation soit bien accueillie217 ? Je prends la liberte´ de vous faire cette ` tout a` fait confidentielle. question d’une maniere ´ e´ heureux de la nouvelle position de M.Painleve. ´ 218 Son influence J’ai et ´ erale ´ dans la politique gen ne fera que croˆıtre de jour en jour. Je pense que vous aussi serez passe´ a` des nouvelles fonctions. Y a-t-il rien de nouveau par rapport au voyage qui prendrait maintenant de nouvelles proportions.
Volterra to Borel Roma, 9 October 1917 Mon cher Ami, ´ J’ai l’honneur de vous presenter et de vous recommander Monsieur le ´ Capitaine Professeur Gallo219 qui est attache´ a` l’Institut Central Aeronautique 217
After Painlev´e introduced the Russian engineer Konstantin Chilowsky to him in July 1915, Langevin developed an important research program on the detection of undersea obstacles (threats), leading to the discovery of the hydrophone in 1915 (the patents are available on http://www.ob-ultrasound.net/chilo lange patents.html; they were deposited by Langevin and Chilowsky in France on May 1916 and in the United States on May 1917). The first known sinking of a submarine detected by hydrophone was the German U-Boat UC-3, in the Atlantic on 23 April 1916. In 1917, using piezoelectricity techniques, Langevin and his collaborators build the first ultrasonics detector, the sonar. In June 1917 during an Allied Submarine Conference in Washington, Britain, France, and the United States had agreed to work cooperatively. The absence of the Italians from this meeting may explain Volterra’s confusion. It is unclear whether Volterra entered in contact with Langevin. Langevin’s first letter in Volterra’s archives dates from 1922, and from its tonality, it does not seem that the two men had been very close. However, on 6 December 1917, received the following strange communication from the Italian Minister of Navy. Object: Underwater hearing Personal – Top secret To the honorable Senator Volterra Chamber of Senate Roma The present minister would be interested to learn what point have reached the studies followed in France on the location by echo of submarines, studies which were begun by Prof. Langevin who is supposed by the present minister to be in personal contact with your Excellency. It would be a benefit for the Country to learn more on the aforementioned subject and I rely on your Excellency’s patriotism to use personal contacts for obtaining this information. We do not know whether Volterra accepted the patriotic mission (a politically correct expression for spying). On Langevin and his connections with Borel, see for instance C. Bigg: De la Belle Epoque aux ann´ees folles. Quel a e´ t´e l’impact de la premi`ere guerre mondiale sur les sciences franc¸aises?, to appear. 218
On 12 September 1917, Painlev´e became Prime Minister, a function he kept only two months due to the very tense military situation. See the following letters.
219
Gino Gallo (1877–1958), had studied chemistry at the University of Padua. In 1913, he founded a laboratory of aeronautical technology for the Ministry of War, later included in the ICA (see the following note). In 1920, he was sent to Germany as a member of the Inter Allies Commission of control for Chemistry and Aviation.
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´ dont le Directeur est Monsieur Crocco220 que vous avez connu l’annee ` a` Rome. derniere Je serai heureux si vous voudrez bien le recevoir et je ne doute pas que ˆ vous pouvez lui etre utile. ´ Je vous ai ecrit il y a peu de jours, mais j’ajoute deux lignes pour vous dire que bien probablement nous aurons besoin d’autres appareils C.W.221 ´ et nous esperons beaucoup dans votre appui pour les obtenir. ´ Veuillez accepter, mon cher Ami, l’expression de tout mon devouement ` affection. et de ma plus sincere Vito Volterra
Volterra to Borel n.p., n.d.222 Mon cher Ami, ´ enements ´ ` ma derniere ` lettre. Ce qu’on peut Bien d’ev sont survenus apres ´ [dire?] est que le pays garde tout le calme et que la volonte´ de resister et de supporter tous les sacrifices est unanime. Une fois encore nos ennemis ˆ n’ont pas compris notre ame. Ils croyaient produire des divisions en Italie ´ e´ justement oppose´ et l’invasion du territoire a rallie´ autour mais l’effet a et ˆ du drapeau meme ceux qui gardaient encore des sentiments pacifistes. Je n’ai pas besoin de vous dire tous nos sentiments de gratitude vers ´ ereuse ´ la France et la gen initiative de Monsieur Painleve´ d’envoyer en ´ ıques soldats.223 La constitution d’un front unique s’est enfin Italie vos hero¨ 220
In 1908 Volterra and Arturo Crocco (1877–1968), an extraordinarily active military engineer who was passionate of aeronautics and dirigibles, had founded the Central Institute of Aeronautics (Istituto Centrale Aeronautico, ICA), where the first courses of Aeronautics in Europe were given, closely followed by the Ecole Nationale Sup´erieure d’A´eronautiquecreated in 1909 in Saint-Cyr (see below footnote 334). In 1915 the Corps of Military Aeronautics under the Ministry of War was founded in Italy, based on the ICA which represented all the Italian Air Force at that time. An interesting biography of Crocco can be found on the website of the Italian Ministry of Defense http://www.aeronautica.difesa.it/SitoAM/Default.asp?idsez=726& idarg=1588& idente=177 221
See footnote 101.
222
The context of the letter clearly shows that it was written few days after the disaster of Caporetto on 24 October 1917. On this day the Italian troops retreated before an Austro-German offensive on the Isonzo front, northwest of Trieste. Total military collapse threatened until November 7, when the Italian line held at the Piave River near Venice, some 110 km from the Isonzo front. The defeat prompted Italy’s allies, France and Great Britain, to send reinforcements and eventually to establish the Supreme War Council to unify the Allied war effort. See Caporetto (Battle of), Encyclopædia Britannica, 2008.
223
See footnote 231.
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´ ´ Il faut continuer a` travailler pour une liaison complete ` dans tous les realis ee. domaines. ˆ ´ e´ au front avec Monsieur Danjon224 pour controler les C.W.225 On a J’ai et ` que Monsieur Danjon pourra continuer tout observe´ [?] en ordre et j’espere ´ ses instructions sans difficultes.
Borel to Volterra Ste Maxime, 28 November 1917 ˆ Ste Maxime (Var) – Grand Hotel Mon cher ami, ´ Voila` bien longtemps que j’aurais voulu vous ecrire longuement et que ´ le loisir m’a fait defaut. Enfin les hasards de la politique226 m’ont donne´ par ricochet quelques jours de repos dont j’avais grand besoin, car j’ai rarement ´ e´ aussi fatigue´ que ces derniers mois. Je crois d’ailleurs que tout le monde et ´ 227 et surtout nos ennemis; mais, chez nous, tout au moins, la est fatigue, ´ fatigue n’entraˆıne pas le decouragement et n’exclut pas la ferme volonte´ de ´ tenir ferme autant qu’il sera necessaire. ´ nous ne pensions Lorsque nous parlions du voyage en Italie de Painleve, certes pas qu’il se produirait a` un moment aussi tragique.228 Cela fut pour lui ˆ ˆ ´ une grande joie d’etre a` meme de prendre une decision rapide au moment ´ a pu retablir ´ le plus difficile. Il semble qu’aujourd’hui votre armee brillam´ ment la situation; nous suivons toujours avec une attention passionnee ´ enements ´ ´ ´ ces ev qui, on peut l’esperer, auront comme principal resultat de resserer encore les liens de nos deux pays.
224
See footnote 203.
225
See footnote 101.
226
At the end of the exhausting year 1917 (see footnote 227), after the disaster of Caporetto on the Italian front, a majority of deputies voted against confidence to Painlev´e’s Government on 13 November. If one reads the Figaro comments on 14 November, Painlev´e’s defeat at the Chamber was unexpected, something which may be felt in Borel’s expression the chances of politics. President Raymond Poincar´e called on Georges Cl´emenceau to form a new Government. 227
The fact that Borel, usually so temperate, mentions how tired he was is highly representative of the after-effect of the terrible year 1917 in France. In April 1917, the failure of the disastrous Nivelle offensive on the Chemin des Dames resulted in the development of mutinies which grew until July. On 15 May 1917 General P´etain had been nominated at the head the General Headquarters of the French armies and he decided to apply a repression policy alleviated by some concrete means to improve the soldiers’ everyday life. Added to several other severe complications of the situation on the international stage (the Russian revolutions in the first place), these events led to a general exhaustion of the population.
228
See footnote 222.
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` que vous avez pu lui donJ’ai eu de vos nouvelles par Danjon229 ; j’espere ´ ner les moyens de rendre tous les services qu’il desire rendre. Maintenant ` que je ne suis plus au Ministere, c’est avec grand plaisir que je remplirais, si ´ ´ une mission analogue a` la sienne. Mais je crains qu’on ne j’en etais charge, ˆ de poursuivre l’etude ´ ´ me charge plutot theorique de questions d’artillerie. Reviendrez-vous prochainement a` Paris? Je compte y rentrer vers le 15 ´ decembre et y passer quelques semaines avant de reprendre le service aux ´ armees. ´ Presentez, je vous prie, mes hommages a` Madame Volterra et croyez ´ ´ moi toujours votre bien affectueusement devou e. Emile Borel
Picard to Volterra Paris, 3 December 1917 Cher ami, ´ Je m’empresse de vous faire savoir que l’Academie des Sciences vous ` ´ a nomme´ cet apres-midi Associe´ etranger a` la presque unanimite´ des suf´ frages. Veuillez recevoir mes affectueuses felicitations. ` que maintenant tout Nous avons bien pris part a` vos angoisses. J’espere ´ danger est ecart e´ pour votre pays. Nous sommes a` un tournant de la guerre ´ avec cette defection honteuse de la Russie, mais nous tiendrons le coup ´ mais l’essentiel est sans elle. La guerre malheureusement sera prolongee, ´ de delivrer le monde du cauchemar germanique. ´ ´ Nous avons lundi prochain la seance publique de notre Academie; je ´ prononcerai l’eloge de Darboux.230 ´ ´ Croyez, cher ami, a` mes sentiments les plus cordialement devou es, Emile Picard
229
See footnote 203.
230
See footnote 238.
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Volterra to Borel n.p., 7 December 1917 Mon cher Ami, Je vous suis fort reconnaissant de votre aimable lettre. Je ne doute pas ˆ ` l’enorme ´ que vous devez etre bien fatigue´ apres travail que vous avez fait dans les derniers temps. Je n’ai pas besoin de vous dire toute notre reconnaissance pour l’envoi ´ ´ 231 Monsieur Painleve´ par la rapide resolution prise de vos vaillantes armees. ´ de notre part a montre´ des sentiavant que toute demande lui fut ˆ arrivee ments d’amitie´ et de solidarite´ vers nous que l’Italie n’oubliera jamais. Et je ` suis sur ˆ que vous avez pris une part bien active dans tout cela de maniere que je tiens a` vous exprimer tous les sentiments de gratitude. ` heureux si vous veniez en Italie. Pourriez-vous venir comme Je serai tres ´ ´ representant des inventions? Cela vous donnerait l’occasion de sejourner aussi a` Rome et au front et je pense que cela serait fort utile. A ce propos je voudrais bien connaˆıtre dans quelle situation se trouvent maintenant les bureaux des inventions en France. Je n’ai pas pu avoir ˆ des renseignements exacts meme en m’adressant a` l’Ambassade a` Rome. Les journaux ne donnent que des courtes notices. Il paraˆıt que le Sous´ e´ supprime´ qui est a` la ´ secretariat des inventions n’existe plus?232 Et s’il a et direction des bureaux? Vous m’obligerez beaucoup si vous voudrez bien me ` utiles pour les rapports donner des renseignements. Ils nous seraient tres de notre bureau avec Paris. ` fois dans ´ e´ deux fois au front pour Monsieur Danjon.233 La premiere J’ai et ´ e´ ensemble de Rome les premiers jours de Novembre lorsque nous avons et ´ e´ aussi tout dernierement ` ´ au front. J’y ai et pour voir a` quel point etaient
231 After Caporetto, the British and French Prime Ministers Lloyd George and Painlev´e rushed up to Rome on 4 November 1917 in order to organize with Generals Foch and Robertson a FrancoBritish military support to Italy. On 10 November 1917, French and British troops were sent. These troops were often considered with mixed, if not hostile, feelings by many Italians who hoped that Caporetto may have concluded the war. One can find interesting comments on this topic in Guiral’s paper ([25], pp. 49–65). 232 Painlev´e brought the Jules-Louis Breton’s position of Sous-Secr´etaire d’Etat aux Inventions down with his Government. However, on 20 November 1917, a ministerial decree of the new Cl´emenceau’s Government created the Direction des Inventions, des Etudes et Exp´eriences thechniques (Direction of Inventions, Studies and Technical Experiences) under the same Jules-Louis Breton (see footnote 257). On 26 November 1918 it was transfered to the Ministry of War and on April 14th, 1919 to the Ministry of Public Instruction. Finally, on December 29th, 1922 it was transformed into the Office National de Recherche Scientifique Industrielle et des Inventions that was in 1938 one of the components of the new Centre National de la Recherche Scientifique et Appliqu´ee. On this subject, see [50]. 233
See footnote 203.
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les travaux. Or j’ai vu que les parties qui lui manquaient des appareils ont ´ e´ envoyees ´ et qu’il va les recevoir. Pour ma part j’ai fait tout ce qu’il etait ´ et ˆ ˆ possible pour lui faciliter sa tache. Je compte le rejoindre au plus tot. ´ a` longtemps que je desire ´ Il y a dej me rendre a` Paris, mais je suis tellement pris par les travaux de mon bureau, et je dois courir un peu partout a` cause des travaux que l’on fait dans plusieurs endroits que je n’ai jamais ´ ´ pu jusqu’a` present. Mais je pense que dans les premiers jours de l’annee ` utile de pouvoir m’entretenir prochaine je ferai le voyage. Il me serait tres ` technique. Je ne puis avec vous sur une foule de questions de caractere ´ eter ´ que vous rep que si on vous confie une mission en Italie vous serez ´ d’une grande utilite. ´ e´ elu ´ Membre associe´ de Je viens de recevoir la nouvelle que j’ai et ´ l’Academie des Sciences.234 C’est un grand honneur pour moi et j’en suis ` fier. C’est le plus grand honneur auquel un savant peut aspirer et ce tres ´ nouveau lien [?] avec l’Academie de votre patrie a` laquelle je suis lie´ par ´ ´ tout mon cœur m’a profondement touche. ´ Veuillez presenter tous les hommages a` Madame Borel de la part de Madame Volterra aussi, et veuillez accepter, mon cher Ami, l’expression de ´ toute mon affection et de tout mon devouement. Vito Volterra
Borel to Volterra Ste Maxime, 10 December 1917 Mon cher ami, ´ C’est ici que je viens d’apprendre votre election a` l’Institut.235 Permettez ´ ´ moi de vous en feliciter et d’en feliciter nos deux pays. Je vais rentrer a` Paris le 17; je ne sais encore ou` j’irai ensuite. ´ Presentez mes hommages a` Madame Volterra et croyez moi toujours ´ ´ votre affectueusement devou e. Emile Borel 234
On December 3rd, 1917, the Paris Academy of Science proceeded to the election of a foreign Associate to replace the vacant seat of the German Physicist Johann Wilhem Hittorff (see footnote 174) who died (appropriately. . . ) at the very beginning of the war. Interestingly, since 1914, nobody had been elected to replace him because of the delicate question of the German associates of the Academy. Out of 43 voters, Voltera obtained the unchallenged number of 38 votes in the first and only round. His three challengers were Anglo-Saxons (two were Americans – Edison and Pickering – and one British – Lockyer). 235
See footnote 234.
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Borel to Volterra Ste Maxime, 13 December 1917 Mon cher ami, Merci pour votre bonne lettre; c’est avec grand plaisir que je viendrais en Italie, mais je ne sais si cela me sera possible. ´ Il n’y a rien de change´ au secretariat des Inventions, sauf que M.Breton236 ´ a le titre de Directeur au lieu du titre de ss secretaire d’Etat. Ma femme me charge de son meilleur souvenir pour Madame Volterra ´ de mon affectueuse et pour vous; veuillez accepter l’expression renouvelee ´ amitie. Emile Borel Je serai a` Paris le 17.
Volterra to Borel n.p., n.d. [December 1917] (draft) Mon cher Ami, ` que vous avez rec¸u un tel ´ egramme ´ J’espere que je me suis empresse´ 237 ` ´ ainsi qu’un de vous envoyer des que j’ai eu la nouvelle de mon election ´ ´ ´ ´ ´ telegramme que j’ai envoye aux secretaires perpetuels pour vous prier de ` ´ vouloir bien manifester a` tous les confreres de l’Academie mes sentiments de profonde reconnaissance. ´ Je tiens a` vous ecrire pour vous renouveler mes remerciements les plus ´ chaleureux. Je sais bien que c’est a` votre interessement et a` votre amitie´ pour moi que je dois ce grand honneur: le plus grand honneur auquel un savant peut aspirer. ´ e´ me trouver a` Paris au moment ou` vous prononcerez J’aurais bien desir ´ ´ e´ a` Paris m’est impossible l’eloge de Darboux238 mais un voyage si precipit ´ dans ce moment etant pris ici par une foule de questions d’ordre technique ainsi que d’ordre didactique. Notre bureau de recherches pour la guerre se ´ developpe de jour en jour pour que le domaine de son activite´ ainsi que le 236
See footnote 257.
237
See footnote 234.
238
The mathematician Gaston Darboux (1842–1917) died on 23 February 1917. The usual public tribute at the Acad´emie des Sciences (to which belonged Darboux) was read on December 10th, 1917 by Emile Picard. The text may be found at the address: http://www.academiesciences.fr/membres/in memoriam/Picard/Picard pdf/Picard Darboux.pdf .
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personnel soit toujours en augmentant. D’autre part notre association pour l’entente intellectuelle, qui a rec¸u de votre part bien d’encouragements, s’est ´ de concretiser ´ ´ proposee [?] dans un projet de loi la question des echanges ´ ´ eves. ` ´ de professeurs, d’etudiants et d’el Le ministre est favorable a` cette idee ` que bientot ˆ la loi soit adoptee. ´ et j’espere ` les jours penibles ´ ´ sont Les nouvelles de la guerre apres qui sont passes maintenant bien confortantes. Nous n’oublierons jamais le prompt [?] con´ a` notre front. C’est une nouvelle et eclatante ´ cours de votre vaillante armee ´ ıque pays nous a donnee. ´ preuve de solidarite´ que votre hero¨ ´ e´ dernierement ` J’ai et plusieurs fois au front et j’ai pu constater ´ l’amelioration de la situation. ´ egraphi ´ ´ Comme je vous ai tel e´ j’en ai ressenti une emotion profonde et d’autant plus mes sentiments de gratitude [?].
Volterra to Borel n.p., 22 January 1918 (draft) Mon cher Ami, ´ J’ai rec¸u votre aimable carte et j’ai informe´ le Conseil de Presidence de ´ ´ l’Academie dei Lincei de ce que vous m’avez ecrit. Le Conseil comprend toute l’importance des pourparlers qui auront lieu a` Londres et il serait ´ heureux de pouvoir s’associer a` l’Academie des Sciences de Paris. ´ Le President m’a adresse´ a` ce sujet une lettre que j’aurai l’honneur de vous montrer sous peu car je pense que je viendrai a` Paris dans quelques jours pour des questions se rapportant a` mon bureau.
Volterra to Borel Roma, 23 January 1918 Mon cher Ami, ` Je suis heureux de pouvoir vous annoncer d’une maniere tout a` fait ˆ ´ ´ confidentielle que vous allez etre nomme´ Membre etranger de l’Academie ` celle qui a des Lincei.239 Il faut attendre encore une nouvelle votation apres ´ eu lieu tout recemment, mais il n’y a pas de doutes qu’elle vous sera aussi ´ ` aujourd’hui. favorable: C’est pourquoi je vous adresse mes felicitations des ` J’espere vous voir sous peu. Je compte me rendre a` Paris dans la semaine prochaine. Monsieur Danjon que j’ai vu il y a peu de jours au front,
239
See footnote 242.
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` que le m’a dit que vous ne viendrez pas maintenant en Italie, mais j’espere ´ projet que vous aviez fait de venir ici ne sera pas abandonne. Veuillez accepter, mon cher Ami, l’expression de mon amitie´ la plus ´ affectueuse et de tout mon devouement. Vito Volterra
Borel to Volterra Paris, 2 February 1918 Mon cher ami, Laissez moi vous remercier de la nouvelle que vous m’annoncez et de la part que vous y avez eue: je sais que c’est a` votre amitie´ et a` votre ` honore. ´ bienveillance que je dois cette distinction dont je me sens tres ´ ` Je suis en ce moment aux armees et je ne passe a` Paris que tres rarement; j’ai obtenu le commandement d’une batterie de canons de 155mm ´ ˆ beaucoup. Peut-etre si a` grande puissance (Filloux)240 et cela m’interesse vous venez a` Paris pourrez-vous savoir ou` je me trouve (car je vais changer ` prochainement de place) et si vous pouvez venir me voir aux armees, ´ tres ˆ vous accomcela me ferait le plus grand plaisir (Percin241 pourrait peut-etre pagner). ´ ´ et reconnaissants. Croyez a` mes sentiments affectueusement devou es Emile Borel
240
Since 1917, the French Headquarters had ordered the production of numerous 155mm guns from the weapons manufactures. The inventor of this model in the manufacture of Bourges, Colonel Louis Jean Franc¸ois Filloux (1869–1957), is an interesting example of an officer-engineer. Details can be found on the website of his birthplace Pontlevoy (http://www.sitepontlevoy.com ). About the French artillery in 1917 and the numerous problems encountered in the introduction of heavy artillery, an interesting American point of view can be found in H.A. De Weerd: American adoption of French Artillery 1917–1918: The journal of the American Military Institute, vol. 3, 2, 1939.
241
See footnote 60.
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Hadamard to Volterra Paris, 2 February 1918 Mon cher ami, ´ e´ l’homme Je ne suis plus heureux de grand chose, et je n’ai jamais et ´ que les honneurs et les titres ont seduit. Mais je veux dire a` votre amitie´ ´ ´ et que cet honneur m’est que, cette fois, je me sens reellement honore, 242 ´ infiniment precieux. ` Je puis dire que je suis doublement touche´ d’en apprendre la premiere nouvelle par vous qui, sans aucun doute, avez infiniment contribue´ a` me le ` doux que le fait d’entrer aux Lincei valoir. C’est pour moi un sentiment tres ˆ ´ ´ a` a` s’accompagne de celui d’etre associe´ a` vous, comme nous l’etions dej ´ l’Academie de Paris.243 ´ dont je sens tout le Encore une fois, cher ami, merci pour votre pensee prix, et croyez moi ´ ´ Votre bien amicalement et profondement devou e´ J. Hadamard
Borel to Volterra n.p.244 , 28 February 1918 Mon cher ami, ` loin de l’endroit ou` vous m’avez vu; je serai tres ` heureux Me voici tres d’avoir de vos nouvelles et de savoir que vos travaux balistiques trouvent leur ` ` Pierre application. Je suis passe´ a` Paris dernierement voir mon beau-frere ´ Appell qui revient d’Autriche ou` il etait prisonnier.245 Il nous dit combien la vie 242
He was elected a member of the Academy of Lincei. On p. 454 of the Rendiconti della R. ´ Accademia dei Lincei, s. 5, vol. 27 I (1918) one can read that the foreign members Borel Emile, ´ Goursat Edouard (Mathematics), Hadamard Jacques, Lamb Horace (Mechanics) are elected.
243
Hadamard refers to Volterra’s election of a member of the Academy of Sciences of Paris. See footnotes 174 and 234.
244
Postcard with a stamp: LE LIEUTENANT EMILE BOREL Ct la 6e Batterie du 88e R´egt d’A.L. (3e Groupe). Par B.C.M. Paris.
245
Pierre Appell, Marguerite Borel’s brother had been taken prisoner by the Austrians when the submarine Monge, on which he was first mate, was sunk in the Adriatic sea on 28 December 1915. Because of bad physical condition, he was freed from Salzerbad camp in AustroHungary and exchanged in February 1918 with several ill captive German officers. Details on the sinking of the Monge can be found in [39] (p. 166) and on the memorial website http://monge.perso.cegetel.net/sousmarinmonge//recit/defaultMenu1.htm. A list of the prisoners
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est difficile la` bas, surtout dans les villes. J’ai vu M.Breton,246 qui m’a parle´ de votre projet commun en ce qui me concerne; je lui ai demande´ au moins ´ ˆ ´ ´ un mois de repit; peut-etre alors vous ecrira-t-il pour vous suggerer de faire faire par votre gouvernement une demande officielle. ´ Veuillez presenter mes hommages a` Madame Volterra et accepter mes ´ plus cordiales et affectueuses amities. Emile Borel
Volterra to Borel n.p., n.d. [March 1918?] Mon cher ami, ` mon arrivee ´ j’ai ecrit ´ Je tiens a` vous dire que des a` Paris pour avoir le plus ˆ possible les . . . [sic; maybe Volterra did not remember the French word for the tot device he mentioned] et l’appareil a` chute, ainsi que pour solliciter l’envoi et ´ la construction des rupteurs. Je pense qu’il serait bien que vous en ecriviez aussi a` Monsieur Breton.247 ´ Veuillez bien m’ecrire et me donner de vos nouvelles. Cela me fera beau´ coup de plaisir ainsi que de savoir que les constructions sont commencees ˆ possiavec votre pleine satisfaction. Je serai heureux de revenir le plus tot ble.
from the French submarines (including Pierre Appell) was published in the Gazette des Ardennes (n. 479 from 21 October 1917 p. 622). 246
Jules-Louis Breton (1872–1940), a French chemical engineer, had been nominated SousSecr´etaire d’Etat aux Inventions int´eressant la D´efense nationale in December 1916. He remained in this position until the suppression of the position in November 1917 and then became the head of the Direction des Inventions (see footnote 232). For details on Jules-Louis Breton, one may refer to [18]. 247
See footnote 257.
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Borel to Volterra n.p.248 , 17 April 1918 Mon cher ami, C’est seulement hier que j’ai rec¸u la lettre m’annonc¸ant la nomination que vous m’aviez fait connaˆıtre par avance et que je dois a` votre bienveil´ Je ne veux pas tarder a` vous renouveler l’expression de mes lante amitie. remerciements pour cette nouvelle marque d’affection. Ma batterie a fait beaucoup de chemin depuis un mois; cette vie active me plait beaucoup et me repose de la tension intellectuelle excessive qui ´ e´ imposee ´ par mes fonctions au Ministere. ` m’avait et Dans les circonstances actuelles, il ne m’est pas possible de songer aux projets que nous avions faits au sujet d’une mission en Italie; lorsque notre ´ il sera sans doute possible de reprenpays sera moins directement menace, dre ce projet.249 Comptez-vous venir prochainement en France? Vous pouvez toujours ´ ´ peut-etre ˆ savoir a` Paris ou` je me trouve et, si ce n’est pas trop eloign e, pourrons nous nous rencontrer. ´ Veuillez presenter mes hommages a` Madame Volterra et accepter ´ de mon affectueux devouement. ´ l’expression renouvelee Emile Borel
Volterra to Borel Rome, 4 May 1918 Mon cher Ami, Je suis heureux d’apprendre que vous avez rec¸u la lettre officielle qui ` ´ annonce votre nomination a` l’Academie des Lincei.250 Nous sommes tres
248 Paper with headings of the Ecole Normale. Stamped: LE LIEUTENANT EMILE BOREL Ct la 6e Batterie du 88e R´egt d’A.L. (3e Groupe). Aux arm´ees. 249
In March 1918, anxious to effect decisive actions before the arrival in France of American troops, and freed on the Eastern front by the Bolshevik revolution in Russia (the Brest-Litovsk agreement was signed on 3 March 1918), the German headquarters tried a powerful attack on the western front. On 21 March began the so-called battle of Picardie and Paris was bombed by long-distance range guns from 23 March. This first 1918 German offensive was stopped on 26 April after the desperate (and successful) resistance of the Franco-British armies. See also footnote 259 below.
250
See footnote 239.
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´ de vous avoir parmi nos membres et j’espere ` bien que vous pourrez honores ˆ assister aux seances ´ ´ bientot de l’Academie a` Rome. ´ Je n’ai fait aucune demande pour avoir un representant Franc¸ais dans notre bureau. J’attends que vous pouvez venir et alors je ferai une demande ` alors qu’il n’y aura aucune difficulte´ et que vous pourrez officielle. J’espere rentrer a` Rome et au front Italien. Je comprends bien que dans le moment actuel votre position dans votre batterie a la plus grande importance, mais le temps viendra ou` nous pourrons reprendre nos projets qui ne sont pas ´ abandonnes. ´ ` ´ ıque Veuillez accepter les felicitations les plus sinceres pour l’œuvre hero¨ ˆ ´ 251 et pour celle que vous meme accomplissez. L’admiration de votre armee ´ Franc¸aise est immense. il n’y a rien de pareil dans l’histoire. pour l’armee Vous avez sauve´ une fois encore la civilisation. Je suis en train de partir pour Paris et pour l’Angleterre. Soit en allant soit ` de vous voir. en revenant j’espere ` et plus affectueuse Veuillez accepter l’expression de ma plus sincere ´ amitie´ et de mes sentiments de haute estime et devouement. Vito Volterra
Volterra to Borel Manchester, 28 May 1918 (draft)
Hulme Hall, Victoria Park, Manchester. Mon cher Ami, ´ pour me faire part que vous venez a` Paris Monsieur Giordano252 m’ecrit du 30 Mai au 2 Juin. Je regrette beaucoup de ne pouvoir pas me trouver a` Paris pour cette date. Je ne rentrerai que le 6 Juin a` Londres ou` je dois ˆ m’arreter quelques jours. Je ne serai de retour a` Paris que vers le 11 ou 12 ´ Juin. Je vous ecrirai de Londres quand je pourrai fixer plus exactement la date de mon retour. ´ et ˆ les ev ´ enements ´ Nous suivons avec le plus grand inter de la guerre. Je ´ eter ´ ´ ıque armee ´ n’ai pas besoin de vous rep toute l’admiration pour votre hero¨ qui s’accroit de jour en jour.253
251
See footnote 249.
252
See footnote 180.
253
See footnotes 249 and 259.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Borel to Volterra Paris254 , 1 June 1918 Mon cher Ami, ˆ Si vous arrivez a` Paris aujourd’hui samedi, peut-etre pourriez vous me ´ ephoner ´ tel a` l’Ecole Normale Gobelins 06-45 ou` je serai jusque vers 1h ` 1/2. J’ai plusieurs courses a` faire dans l’apres-midi, je passerai a` la fin de ´ (vers 6h) au Ministere ` des Inventions si vous y allez pour voir la journee ˆ leur dire ou` je vous M. Buisson255 et M. Breton256 vous pourrez peut etre trouverai a` 6h. ´ a` l’Ecole Dimanche, je pense que je serai une grande partie de la journee Normale; je repars le soir pour le front. Il n’y a aucune difficulte´ a` la publication dont vous me parlez, du moment ´ qu’il ne s’agit pas d’une traduction d’un ouvrage complet. Si votre editeur le ´ juge utile, je pourrais ecrire a` M. Alcan257 et a` M. Gauthier Villars,258 mais cela me paraˆıt superflu. ˆ pourrions nous Si les affaires deviennent plus calmes ici,259 peut-etre ´ realiser notre projet. M. Breton260 vous en parlera. Il y a quelque susceptibilite´ chez M. Giordano.261 En ce qui me concerne, je m’engagerais bien ˆ volontiers a` ne pas etre en concurrence avec lui – c’est a` dire a` ne pas 254
Paper with letterhead of the Hˆotel Lutetia.
255
We were not able to find a precise document to decide who was the Buisson mentioned by Borel. According to [2] , p. 338, the intended person is Georges Buisson, one of the closest political collaborators of Paul Painlev´e, a socialist republican member of Paris City Council on whom we possess very few personal data. However, it is perhaps more reasonable to think that Borel refers to Henri Buisson (1873–1944), the French physicist who discovered the ozone layer together with Charles Fabry in 1913 because of the connection to invention. 256
See footnote 257.
257
The important publisher F´elix Alcan (1841–1925) founded a publishing house specializing in science, history and philosophy in 1883. Since 1905, Alcan had been the usual partner of Borel and his wife for their numerous publishing projects. See Val´erie Tesni`ere: Un si`ecle d’´edition universitaire. 1860–1968, PUF, 2001. 258
Founded in 1864 by Jean Albert Gauthier-Villars, the Gauthier-Villars publisher was specialized in sciences. This publisher-printer-bookseller published the Annales Scientifiques de l’Ecole Normale Sup´erieure (since 1864), the Bulletin des Sciences Math´ematiques (since 1870), and the Bulletin de la Soci´et´e Math´ematique de France (since 1873) becoming for more than a century a kind of official publisher for French mathematical science.
259
June and July 1918 saw the last German offensives of the war on the Western front before the presence of the American troops reversed the situation. On 30 May, for the first time after 1914, the Germans reached the Marne at Chateau-Thierry. After the last offensive in Champagne on 15 July, during the so-called second battle of the Marne, the general counter-offensive of the Allies began and lasted until the end of the war.
260
See footnote 257.
261
On Giordano, see footnote 180.
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faire les transmissions dont il s’acquitte si bien – car il me semble qu’il y a beaucoup de travail utile a` faire en dehors de celui-ci. ´ Veuillez presenter mes hommages a` Madame Volterra et me croire tou´ ´ jours votre bien affectueusement devou e. Emile Borel
Borel to Volterra n.p., 20 August 1918 Mon cher ami, Votre lettre du 3 aout ˆ m’est parvenue avec un grand retard parce qu’elle a ´ e´ re´ exp ´ edi ´ ee ´ a` ma femme qui etait ´ ´ au bord de la mer et que de mon et allee ˆ e´ je me suis deplac ´ cot e´ plusieurs fois ce qui a retarde´ ma correspondance. J’ai eu la chance de me trouver dans un des secteurs ou` notre avance ´ e´ importante et de remettre le pied sur les regions ´ ´ la veille par a et quittees ´ de notre vie habituelle est cependant l’ennemi.262 Cette vie bien differente ` passionnante et je ne voudrais pas la quitter en ce moment. M. Mautres ´ ` que votre demande lui sera parvenue cependant des rain263 me previendra ` et nous examinerons alors ce qu’il est possible de faire, car je suis aussi tres ` reconnaissant de la peine que tente´ par votre proposition et vous suis tres vous avez prise et qui ne sera pas perdue, a` moins que le gouvernement ´ franc¸ais n’y trouve des objections graves, ce que je ne prevois pas. ´ Veuillez presenter mes hommages a` Madame Volterra et accepter ´ l’expression de ma bien affectueuse amitie. Emile Borel
Volterra to Borel n.p., n.d. [August/September 1918] (draft) Mon cher Ami, ´ ` des affaires etrang ´ ` La proposition a` votre egard est partie du Ministere eres. ´ J’ai ecrit a` ce sujet a` Monsieur Maurain qui en parlera avec Monsieur Bre-
262
See footnote 259.
263
See footnote 103.
124
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ˆ possible. ton.264 Je serai heureux si je pourrai vous voir chez nous le plus tot Veuillez bien me donner de vos nouvelles. ´ Veuillez accepter toutes mes felicitations les plus chaleureuses et les plus cordiales pour vos nouvelles victoires et pour la part que vous y avez eu.265 ˆ ` de son armee ´ hero¨ ´ ıque qui La France doit etre de jour en jour plus fiere gagne chaque jour des nouvelles batailles et se couvre de gloire. La situ´ erale ´ ´ ee ´ et avantageuse. Je ne doute pas que la ation gen est bien amelior victoire finale s’approche.
Borel to Volterra Paris, 16 September 1918 Mon cher ami, En passant ici j’ai vu M.Buisson266 aux Inventions: il m’a dit que la demande officielle de votre gouvernement ne lui est pas encore parvenue. Je pense que ces retards proviennent, soit d’une erreur d’aiguillage au ´ ´ comme il y en a quelquefois depart, soit plus probablement, de difficultes ` ´ entre certains services appartenant a` des Ministeres differents (je suppose que vous ne connaissez pas cela en Italie). ´ ´ eral ´ Etant donne´ que je depends directement du Grand Quartier Gen 267 ´ ´ eral ´ ´ je pense que l’on eviterait beaucoup de retards et de (Gen Petain), ´ si la demande de votre gouvernement pouvait etre ˆ ´ vers difficultes aiguillee ´ ` a` eviter ´ cette direction – et si j’en etais informe´ de maniere que dans cette ´ maison qui est grande, elle ne s’egare encore. ´ e´ de vous donner encore des ennuis pour une question ou` Je suis desol vous avez montre´ tant d’obligeance active et ou` vous n’avez aucune responsabilite´ dans les lenteurs qui se sont produites.
264
On Breton, see footnote 257. In Volterra’s correspondence, one may find a minute of the mentioned letter probably addressed to Maurain. Volterra mentions, as he does for Borel, that the proposition (for inviting Borel to Italy) had left the Italian foreign office. Volterra concludes this letter by mentioning: “My journey to Paris has also been reported, I shall see if it can take place as soon as possible. Mme Curie is in Italy and tomorrow she will arrive in Rome”. Marie Curie has indeed come to Italy in September 1918 to give advices about the possible extraction of radioactive materials in Lacco Ameno. In Volterra’s archive, there is a single letter by Marie Curie, thanking Volterra for his cordial hospitality (see [46], pp. 150–151).
265 266 267
See footnote 271. See footnote 255. See footnote 227.
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´ e´ particulierement ` ´ La vie que j’ai eue depuis 2 mois a et interessante, et le restera sans doute jusqu’a` l’hiver – ou` il faudra attendre le printemps.268 ´ Presentez mes hommages a` Madame Volterra et croyez moi votre bien ´ cordialement et affectueusement devou e´ Emile Borel Capitaine Comm[andan]t la 28e Bri du 88e d’artillerie.
Volterra to Borel Rome, 20 September 1918 Mon cher Ami, Je viens de recevoir votre aimable lettre. Il n’y a que peu de jours que j’ai ´ e´ arret ˆ e´ a` Paris a` cause de Monsieur Giordano269 qui appris que tout avait et ´ ´ ˆ ´ e´ propose´ et demande´ de etait reussi a` s’opposer et a` arreter ce qui avait et notre part. Mais une nouvelle lettre est partie pour faire savoir qu’on devait se passer de l’opposition de Monsieur Giordano et n’en tenir pas compte. ` confidentielle Monsieur Veuillez bien avertir de tout cela d’une maniere Maurain.270 Je serai a` Paris dans les premiers jours du mois d’Octobre et je partirai ´ ´ de Paris pour me rendre a` Londres ou` il y a la reunion des representants ´ des Academies. ` bien de vous voir a` Paris a` peu pres ` vers le 3 ou 4 Octobre si J’espere vous pourrez vous y rendre a` ce moment. Je n’ai pas besoin de vous dire notre enthousiasme pour les grandes ´ ıques dont ´ 271 Toutes les actions hero¨ victoires des Franc¸ais et des Allies. ´ e´ depass ´ ´ ´ ıques l’histoire rappelle le souvenir ont et ees par les actions hero¨ ´ et dans tous les temps vous que vous avez accomplies. Les peuples civilises en seront reconnaissants.
268
Borel’s observation is rather interesting. It shows that less than two months before the Armistice of 11 November 1918, and despite of the return of military movements after 3 years of static stamping in the trenches, it was not clear that the war would soon come to an end.
269
On Giordano, see footnote 180.
270
See footnote 103.
271
At the end of August 1918, the last German offensive of the war was stopped near Paris and concluded by a final failure (the second battle of the Marne). The German armies then began a retreat which lasted to the end of the war. One can feel in the tone of Volterra’s letter that he had now total confidence that Germany would soon be defeated.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ Veuillez bien, mon cher Ami, presenter mes hommages a` Madame Borel ´ ´ et accepter l’expression de l’amitie´ la plus affectueuse et la plus devou ee. Vito Volterra
Borel to Volterra Paris, 19 October 1918272 Mon cher ami, ˆ J’arrive a` l’instant a` Paris et j’apprends que vous y etes encore pour quelques jours. Vous seriez bien aimable de me faire savoir a` quelle heure ` je pourrai vous trouver chez vous; je suis entierement a` votre disposition ´ eph. ´ (Ecole Normale Tel Gob.06.45) ˆ donc, A bientot ´ Votre bien devou e´ Emile Borel
Borel to Volterra Paris, 23 October 1918273 Mon cher ami, ´ Pourriez-vous me faire le plaisir de dejeuner ou de dˆıner avec moi avant ´ ˆ votre depart? Je passerais vous prendre a` votre hotel quelques minutes avant midi ou avant 7h, suivant vos indications. Si vous pouvez me donner ´ ´ ephone ´ une reponse par tel ce soir Gobelins 06 45, ou demain matin jeudi ˆ avant 8h1/2, ce pourrait etre pour demain jeudi a` midi – sinon pour jeudi soir, ou vendredi matin ou soir a` votre convenance. ` des Affaires Je pense que la communication officielle de notre ministere ` Etrangeres a duˆ parvenir a` votre ambassade ´ Votre bien devou e´ Emile Borel
272
Letter with letterhead Minist`ere de l’Armement et des Fabrications de Guerre. Direction des Inventions, des Etudes et des Exp´eriences Techniques.
273
Letter with letterhead Minist`ere de l’Armement et des Fabrications de Guerre. Direction des Inventions, des Etudes et des Exp´eriences Techniques.
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Borel to Volterra Paris, 26 December 1918 Mon cher ami, ´ L’organisation dont nous avons parle´ va, je crois, se realiser, mais les choses vont plus lentement que je ne l’aurais voulu. D’abord, les choses vont toujours plus lentement que l’on ne voudrait; de plus, une circon´ stance speciale, la maladie de M. Breton274 , qui garde la chambre depuis un mois, a complique´ encore les choses (Il a une grippe intestinale encore fort ´ ´ de Painleve, grave).275 C’est seulement lundi qu’a eu lieu, sous la presidence ´ ´ la reunion d’une commission qui va etudier ce que va devenir la direction ´ de presenter ´ des Inventions; je pense que d’ici un mois nous serons en etat un projet au gouvernement et que nous aboutirons.276 Je vous tiendrai au courant. Malheureusement, cette commission d’une part, et aussi la question de ´ ´ la reprise des etudes a` l’Ecole Normale, qui m’oblige a` des demarches ´ frequentes, ne me permettent pas de quitter Paris en ce moment. Je suis donc oblige´ d’ajourner mon voyage a` Rome; je le regrette bien vivement, car je suis de plus en plus convaincu de l’importance de toutes les actions, ˆ meme les plus modestes, qui peuvent renouer l’intimite´ des deux pays. ` le magnifique voyage de votre Roi, Heureusement, en ce moment, apres ´ e´ dissipes. ´ 277 bien des nuages artificiels ont et
274
On Breton see 257.
275
Let us recall that the Spanish influenza epidemic, which may have been brought to Europe from the USA by the American soldiers arrived in April 1918, had been extremely devastating in the winter 1918–1919 and was responsible for a total of nearly 25,000,000 deaths (much more than the war in fact), in particular among 20- to 40-year-olds, a very unusual mortality age pattern for influenza. Apart from the exceptional virulence of the virus, it is probable that the difficult sanitary situation in Europe caused by the war situation considerably worsened the situation. Though this may be a coincidence, the reader will certainly observe that sentences about the health of several persons frequently appear in the following letters. See “Influenza epidemic of 1918–19.” Encyclopædia Britannica, 2008 and also J. Winter: La grippe espagnole in [4], pp. 943 et seq.
276 277
See footnote 232.
Vittorio-Emanuele III, king of Italy, came to France between December 19th and December 22nd, 1918. Under the surface of enthusiastic comments on the alliance between the two Latin sisters, a rhetoric flourish which was already present at the very beginning of the war in Volterra’s letters (see for example the letter from 14 September 1914 above), one may feel how the unresolved questions of Italian aims of war was beginning to poison the relationship between the Allies. In the Figaro issue of 19 December 1918, an inflammatory text by d’Annunzio appears as a reminder of the Italian sacrifices and righteous claims for the irredente territories. The artificial clouds mentioned by Borel were in fact very tangible and concluded in the failure of the Peace Conference to solve the Italian problem (see [38], Chapter 22).
128
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
´ es ` va probablement etre ˆ M. Per nomme´ a` la faculte´ de Toulouse278 ; vu 279 ` M. Robin et lui ai rapporte´ nos conversations au sujet de son beau-pere ´ es. ` Per ´ se termine mieux qu’on ne l’avait esper ´ e´ a` son debut; ´ L’annee mais on ´ commence seulement a` comprendre le degre´ d’epuisement de l’Europe et ˆ que meme les peuples victorieux perdent beaucoup a` cette guerre. C’est du moins le sentiment qui domine ici, en raison de nos immenses pertes, qu’on n’ose pas avancer ouvertement, mais pour lesquelles cependant les journaux commencent a` imprimer les chiffres terrifiants qui varient entre 1 million et demi et 1 million de morts.280 L’Europe est comme un malade ´ ´ ´ epuis e´ qui a besoin de soins et precautions pour encore une longue periode. ´ ´ Il faut neanmoins se rejouir que la guerre n’ait pas dure´ plus longtemps et ´ e´ totale. Et nous devons commencer l’annee ´ surtout que notre victoire ait et ´ ` ` qui vient avec l’espoir qu’elle marquera le debut du relevement et de l’ere ˆ nouvelle. Je souhaite qu’elle n’apporte que du bonheur aux votres et a` vous ˆ meme et suis heureux de vous renouveler en cette occasion l’expression ´ a` vieille et inalterable ´ ´ d’une dej amitie. Emile Borel
278
See ♥ 7 .
279
L´eon Robin (1866–1947) was a professor of philosophy at the University of Paris since 1913. He had defended a thesis in 1908 about Plato’s theory of Ideas and Numbers. He published a book in 1923, Greek thought and the origins of the scientific spirit (English translation London: K. Paul, Trench, Trubner and Co. Ltd.; New York, A. A. Knopf, 1928 ) (see [12]). Perhaps it is through his interests for science that he was in contact with Borel. Shortly before the beginning of the war, P´er`es had written to Volterra on 15 June 1914 to tell him about his engagement to Genevi`eve Robin.
280
Borel’s sentence is obviously related to the slowly decreasing censorship which allowed newspapers to provide more and more reliable figures about the casualties, and also to the clarification of the status of missing persons such as prisoners. Borel should have been more sensitive than anyone else to the significance of large numbers in social phenomena, a recurrent theme in his writings about the application of mathematics, in particular of probability theory (in his book Le hasard [9] for instance). The Great War had also been a field of dramatic experiments using large number situations to an up-to-then unreached level. A good (and happy) example of Borel’s delight for numbers in found in the chapter of Le Hasard dealing with Physics, where he gives hints about the probability of a non-equilibrium situation in the mixing of two gases (pp. 160–162).
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Volterra to Borel n.p., n.d. [December 1918] (draft) ´ e´ tres ` heureux et nous avons et ´ e´ tres ` conLe voyage du Roi d’Italie a et ´ e´ rec¸u.281 Nous vous en sommes tents de l’enthousiasme avec lequel il a et ` reconnaissants. J’ai lu en detail ´ ´ tres la reception a` l’Institut.282 Le discours 283 ´ ´ Mone. que M. Paul Girard a adresse´ au Roi d’Italie nous a fort interess ´ sieur Paul Giraud est membre de l’Academie des Lincei c’est pourquoi j’ai pense´ que ses paroles peuvent avoir quelque rapport avec le projet que ` vous avez conc¸u et dont M. Boutroux m’a entretenu dernierement. Au nom ´ egramme ´ de l’ association pour l’entente intellectuelle j’ai envoye´ un tel de ´ ´ felicitations a` Monsieur Girard pour les paroles qu’il a prononcees. S’il y a ´ egramme ´ quelque relation avec votre projet mon tel pourra initier quelques commentaires a` ce sujet. ´ ´ eves ` Le projet pour les echanges de professeurs et d’el que nous avons ´ ´ e´ finalement adopte´ et est devenu une loi de prepar e´ depuis longtemps a et 284 ´ eres ` ´ Monsieur B. . .285 y a introduit quelques leg modifications, mais l’etat. ´ ´ prochaine. il faut esperer des fonds suffisants pour l’annee
281
See footnote 277.
282
On December 20th, 1918, Victor Emmanuel III visited the Acad´emie des Inscriptions et BellesLettres, one of the academies composing the Institut de France, to which he had been elected in 1915 on the official basis of his historical works on medieval Italian coins. A booklet of commemoration was published afterwards: Compte-Rendu de la S´eance du 20 d´ecembre 1918. Visite de Sa Majest´e Victor Emmanuel III Roi d’Italie, Ed.Auguste Picard, 1918. See also footnote 277 and next footnote.
283
The hellenist Paul Girard (1852–1922), as president of the Acad´emie des Inscriptions et BellesLettres, made the welcome speech to the king. At the end of this speech, Girard mentions his hope for developing the scientific links with academies and scientific societies of allied nations. Volterra is probably alluding to this in the following sentence.
284 In the Official Journal of the kingdom of Italy (12 February 1919, n. 36), one can read the following lines. “Under the supervision of the High council of Public Instruction, a section for intellectual relations with foreign countries is created. The section gives advice: (a) On exchanges with foreign countries of university professors, secondary school teachers, assistants, librarians, highly praised researchers and students; (b) on the foundation of institutes for higher education in foreign countries. The section studies and presents all the initiatives dedicated to the improvement of intellectual relations of Italy with foreign countries to the minister.” 285
Sic. Probably, Volterra meant Agostino Berenini (1858–1939), a former socialist, then reformist Italian politician, who was minister of Public instruction between November 1917 and June 1919 in Orlando’s cabinet. He signed the aforementioned law together with Orlando.
130
Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Borel to Volterra Paris, 8 January 1919 Cher ami, En vous envoyant la circulaire que la maison Alcan286 adresse a` nos collaborateurs, je tiens a` vous rappeler ce que je vous ai dit en novembre: ce ´ 287 pouvait renfermer serait une rare bonne fortune si notre premier numero quelques pages de vous. ` que je pourJe vous renouvelle mes meilleurs vœux; je vous enverrai des ´ ´ ici du Conseil national. rai de nouveaux details sur l’organisation projetee ´ ´ Votre affectueusement devou e, Emile Borel
286 287
See footnote 257.
For general information on the Revue du Mois, see footnote 28. After the war, several issues of the journal appeared but it never recovered the spirit of brilliant intellectual exchanges of the old times. Many of the usual collaborators of the journal were now old or busy with other tasks, not mentioning the loss of Borel’s right-hand man Bianconi in 1915 (see [41]). Borel himself seems to have lost the faith he had at the beginning. His political engagement after the war reveals a growing conviction in the need for of direct political action instead of limiting himself to the intellectual spheres. He nevertheless continued to take in charge the direction of a collection of books with the same publisher F´elix Alcan, the Nouvelle Collection Scientifique, a task certainly less heavy than the publication of a monthly journal. As for the Revue du Mois, the journal was published for two years after the war, and in the last issue of December 1920, Borel published a small text announcing that the publication would stop because of financial difficulties. He also mentioned that he conceived the Nouvelle Collection scientifique to be a natural extension of the Revue du Mois. Volterra, who had enthusiastically participated in the adventure of the Revue du Mois 13 years before (he wrote the first paper published by the journal in 1906, an important study about biometrical problems: Sur l’application des math´ematiques aux sciences biologiques et sociales), was in 1919 deeply involved in practical political problems, such as the creation of the Unione Matematica Italiana or the Consiglio Nazionale delle Ricerche (see [36] and Pietro Nastasi and Rossana Tazzioli: Italian mathematicians and the First World War in [21]), and did not show much energy or will to write a new paper as required by Borel. Volterra’s delay (see the following letters) is a good hint of this change of mood. In fact, the paper never appeared (see footnote 300).
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Volterra to Borel n.p., n.d. [January/March 1919] Mon cher Ami ´ J’ai commence´ plusieurs fois a` ecrire l’article que vous m’avez demande´ pour la Revue du Mois288 ; et je pus le continuer jusqu’a` un certain point, ´ e´ interrompu et en eprouvant ´ mais chaque fois mon travail a et une peine infinie car je voyais que je manquais avec vous, je ne suis pas encore arrive´ ´ a` le terminer. Le sujet que j’avais pris a` traiter etait l’œuvre des savants de l’entente pendant la guerre soit pour ce qui se rapporte aux inventions soit ` lent pour ecrire ´ ´ aux rapports intellectuels entre eux. Je suis tres et j’eprouve ` grande difficulte´ pour exposer mes idees ´ sous une forme toujours une tres ´ ´ depuis mon plus jeune age. ˆ litteraire. C’est une difficulte´ que j’ai rencontree ´ e´ si nombreuses et mon temps a et ´ e´ Mais cette fois les interruptions ont et ´ ´ se sont accumulees ´ pris par tant d’occupations differentes que les difficultes les unes puis les autres. Ce sont d’abord mes cours ou lec¸ons que j’ai du commencer, mais devoirs de doyen de la Faculte´ avec les nouveaux cours ´ ´ eves ` supplementaires pour les el revenus du front. La continuation du bureau ´ e´ tres ` reduit ´ des inventions qui a et mais que je n’ai pas voulu interrompre jusqu’a` la constitution du nouveau Conseil de recherches qui est en forma´ ´ a` fait le a` la constitution d’une commission qui a dej tion.289 Je vais reussir projet en prenant pour fondement le bureau des inventions, le laboratoire de M. Ciano [?] ´ eral ´ ´ transforme´ en laboratoire gen de recherches, l’Academie des Lincei, le comite´ des inventions chimiques et le comite´ scientifique et technique. Le ˆ ` projet va etre adopte´ sans peine; mais que de courses dans les ministeres, ´ ´ que d’entretiens avec le ministre du tresor pour avoir les fonds necessaires! ´ Vous qui connaissez la machine bureaucratique pouvez vous faire une idee de ce que j’ai eu a` faire.
288 289
See footnote 287.
The creation of the Consiglio Nazionale delle Ricerche had in fact quite a long gestation as the official birth was only on 18 November 1923 – which is to say at the beginning of the Fascist period. It was already mentioned in [44] that, apart from the usual bureaucratic inconveniences, the very special period of Italian history with unceasing changes of government and Mussolini coming to power are obviously to be taken into account in order to explain the delay.
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Borel to Volterra Paris, 1 February 1919 Mon cher ami, ` que Votre lettre du 5 janvier a mis deux semaines a` me parvenir; j’espere ` l’avoir ecrite, ´ ´ dans vous avez bien rec¸u, apres celle que je vous ai adressee ´ les derniers jours de decembre. Je me permets de renouveler ma demande au sujet de la Revue du Mois.290 Voyez-vous une possibilite´ de me donner quelques pages pour ´ – d’ici un mois ou six semaines – J’y attacherais notre premier numero d’autant plus de prix que ce serait une occasion nouvelle de montrer publiquement notre volonte´ commune de maintenir a` tout prix l’entente intellectuelle entre les deux pays qui est un des fondements les plus solides de l’alliance politique. Je suis tout a` fait d’accord avec vous, je n’ai pas ´ besoin de le dire, pour penser qu’il est necessaire de lutter sur tous les ´ et ˆ a` nous brouiller.291 Il n’est pas douteux terrains contre ceux qui ont inter ´ ˆ ` que dans les grandes decisions qui vont etre prises et qui regleront le sort ´ de l’humanite´ pour de longues annees, il n’y a pas une seule puissance qui ´ ´ n’eprouvera quelque deception et quelque amertume – d’autant plus vives ` ˆ que le reglement paraˆıtra devoir etre plus durable, c’est a` dire sera plus ´ equitable dans son ensemble. Ce qui importe par dessus tout, c’est que les deux nations sœurs ne pensent pas chacune a` rendre l’autre unique et seule ´ responsable de ce qui sera, je crois pouvoir l’affirmer, le fait d’autres allies. ´ ` nettement, Si je ne suis pas juste sur ce point, n’hesitez pas a` me le dire tres ` imparfaitement informe´ de certaines questions: mais car je ne suis que tres ´ on assure ici que ce ne sont pas les Franc¸ais qui sont le moins bien disposes pour les revendications italiennes. ´ e´ assez souffrant ces dernieres ` semaines et n’a pu M. Boutroux292 a et ´ Il m’a dit qu’il tacherait ˆ encore poursuivre le projet dont nous avons parle. ` pris par sa de voir M.Salandra,293 mais il craignait que celui-ci ne soit tres mission officielle.
290
See footnote 287.
291
This sentence, written at the precise moment when the Italian delegation to the peace conference was arriving in Paris, shows the climate of tension between the Italians and their allies, who were becoming infuriated by what seemed exaggerated Italian claims. The Italian memorandum and claims were presented to the Conference on 7 February.
292
On Boutroux, see footnote 18. The project mentioned is probably the scientific links between French and Italian institutions mentioned above (see footnote 283).
293
Antonio Salandra (1853–1931), who had been at the head of Italian Government when Italy entered the war on May 1915, had resigned from this position after one year of unsuccessful military attempts to break the Austrian front. He was a member of the Italian delegation at the Peace conference in 1919 and later became the Italian delegate to the League of Nations.
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Je puis vous dire confidentiellement que l’Universite´ de Paris a l’intention, ´ ´ et probablement assez eloign ´ ´ de noma` une epoque non encore fixee ee, mer un certain nombre de docteurs honoris causa (le seul jusqu’ici est le ´ a` et ´ e´ prononce´ et, je n’ai pas besoin ´ President Wilson294 ). Votre nom a dej de le dire, favorablement accueilli par tous. Je pense qu’on organisera une ´ a` cette occasion.295 belle solennite´ interalliee ´ ´ Votre affectueusement devou e, Emile Borel ´ La Commission interministerielle a abouti a` de beaux projets d’Office ´ a` l’agriculture et a` l’industrie, National des recherches scientifiques appliquees ´ ˆ de laboratoires a` l’Academie, etc. La difficulte´ va etre maintenant d’obtenir de l’argent du Parlement; c¸a ne sera pas facile.296
Picard to Volterra Paris, 12 March 1919 Cher ami, ´ Le Bureau des Longitudes297 vient de faire un projet de determination ´ d’un reseau mondial de longitudes. Je vous en envoie quelques exem´ plaires. Nous desirons que ce projet soit place´ sous le haut patronage du ´ ´ ´ des Academies. ´ Comite´ executif de la Conference interalliee Bien entendu, cette approbation n’engage personne au point de vue financier; les pays
294
Wilson had received the title of Doctor Honoris causa of the University of Paris on 21 December 1918, some days after a ministerial decree had opportunistically given to the Sorbonne the right to attribute this title. Wilson had been in Paris at the same time as the king of Italy Vittorio Emanuele III (see footnote 277) – who seized the occasion to meet the President of the USA. Both events are described in newspapers of the day – see in particular the long front page articles in Le Figaro and L’Humanit´e on 22 December, entitled President Wilson, jurist and historian.
295
See below the letters from December 1919 and the footnotes therein.
296
The inter-ministerial commission mentioned by Borel, directed by Cl´ementel, minister of Trade and Industry, gathered many famous scientists (including Picard, Painlev´e, Appel and Borel himself for the mathematicians). Its discussions resulted in legisltation proposed by the Government to the Deputy Chamber on 27 May 1919. The law was finally adopted on 10 July 1919 (See the Bulletin Officiel de la direction des Recherches scientifiques et industrielles et des Inventions, Tome I: Novembre 1919 a` d´ecembre 1920). 297
The Bureau des Longitudes was founded in 1759 and charged with the compilation of ephemerides and, more generally, of perfecting astronomical tables. In 1854 it was charged with a larger mission to organize several big expeditions: geodetic measurements, observations of solar eclipses, observations of the transit of Venus. It participated in the foundation of many scientific organizations such the Bureau International de l’Heure (1919), the Groupe de Recherches de G´eod´esie Spatial (1971), the Service International de la Rotation de la Terre (1988).
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participants qui seront probablement les Etats-Unis, la France et le Domin´ ´ ´ ion de la Nouvelle-Zelande feront les frais de l’operation. Repondez-moi ´ donc si vous ne voyez aucun inconvenient a` dire que ce projet a rec¸u ´ l’approbation du Comite´ executif. C’est, je crois, un des objets du futur ´ Comite´ international de recherches de recommander certains etudes a` l’attention des Gouvernements. ` que vous etes ˆ ´ ainsi que tous les votres. ˆ J’espere en bonne sante, La ´ d’une maniere ` terrible a` Paris, et il y a eu des cas tres ` graves. grippe a sevi ` une correspondance recente ´ D’apres avec Schuster,298 nous allons sans ´ doute avoir en Juillet une nouvelle reunion. ´ On est assez agace´ a` Paris des lenteurs de la Conference de la paix.299 ˆ ´ C’est peut-etre injuste; il semble cependant que l’on a eu d’abord des visees trop philosophiques et insuffisamment pratiques. Bien affectueusement a` vous, Emile Picard
Borel to Volterra Paris, 13 May 1919 Mon cher ami, ´ ´ e´ fort preoccup ´ Je suis bien en retard pour vous repondre, mais j’ai et e´ ` ces dernieres semaines par la sante´ de ma femme, qui heureusement va beaucoup mieux. ` touche´ que vous ayez trouve´ le temps d’ecrire ´ Je suis tres un article ` que vous me l’apporterez, puisque vous pour la Revue du Mois300 ; j’espere ` annoncez votre prochain voyage a` Paris. Ce voyage co¨ıncidera, j’espere, avec l’arrangement selon vos souhaits des graves questions qui vous 298
Sir Arthur Schuster (1851–1934) was a physicist known for his work in spectroscopy, electrochemistry, optics and X-radiography. He studied in Germany (with Gustav Kirchhoff, Wilhelm Weber and Hermann von Helmholtz) and worked in England; he contributed to transform the University of Manchester into a centre for the study of physics. He served as secretary of the International Research Council (1919–1928) and of the management committees for the Meteorological Office (1905–1932) and National Physical Laboratory (1899–1902, 1920–1925).
299
The Peace conference officially opened on 18 January 1919. Its progresses were extremely slow and it showed a rather chaotic organization. A recurrent stumbling block was the intricate question of the amount of the war reparations to require from Germany. This may be what Picard had in mind in the present letter. The Peace Conference is described in detail in MacMillan’s spicy book [38].
300
About this paper, see footnote 287. In fact, no paper by Volterra was published during the two after-war years of existence of the journal (1919 and 1920). Maybe Volterra did not give it to Borel, or the latter was not satisfied with it.
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301 ´ ´ preoccupent si legitimement. Je pense que ces vissicitudes politiques ´ auront comme resultat final de renouer davantage les liens entre nos deux ´ a` vivre amis et allies, ´ si l’on veut que l’Europe soit stable et pays destines libre. ´ Veuillez croire toujours a` mon affectueuse amitie.
Emile Borel
Borel to Volterra Paris302 , 1 December 1919 DOCTORAT HONORAIRE303 VOUS SERA CONFERE SORBONNE VINGT DECEMBRE FELICITATIONS AMITIES – BOREL –
Borel to Volterra Paris, 1 December 1919 Mon cher ami, ´ egraphi ´ ´ Comme je vous l’ai tel e´ ce matin, c’est le 20 decembre que ` l’Universite´ de Paris vous conferera le grade de docteur honoris causa.304 ´ ´ e´ prise ce matin par le Conseil de l’Universite; ´ le Recteur La decision a et ` qu’elle aura et ´ e´ approuvee ´ par le Gouvous en informera officiellement des ´ Chacune des 5 facultes ´ (Droit, vernement, ce qui est une simple formalite. ´ ´ Medecine, Sciences, Lettres, Pharmacie), a design e´ un seul docteur; vous ˆ ´ etes donc le seul design e´ par la Faculte´ des Sciences; au point de vue ´ pour les 4 autres facultes, ´ il y a deux anglais, 1 belge et des nationalites,
301 On 20 April 1919, the Italian delegation slammed the door of the Peace conference when it appeared that the Italian territorial claims were not sufficiently being taken into consideration. The major problem for the Allies was the determination of the border with the newly created Yugoslavia, the Italians claiming the possession of large territories on the Adriatic eastern coast. The self confidence of the Italian delegates, who obsessively referred to the secret London treaty of April 1915, had exasperated Wilson, Lloyd George and Cl´emenceau, who became inclined to help the weak Yugoslavia. Let us recall Cl´emenceau’s tasty phrase which outraged the Italian Head of Government Orlando: My God, Italy or Yugoslavia? The blonde or the brunette?. In April 1919 Cl´emenceau had definitely chosen the brunette. . . See [38], Chapter 22. 302
The present letter is a telegram.
303
See footnote 294 and below.
304
See footnote 294 and below.
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1 danois.305 Vous savez qu’il n’y a jusqu’ici qu’un seul docteur honoraire de ´ emonie ´ ´ ´ du 20 decembre l’Universite´ de Paris, le president Wilson.306 La cer ´ ´ de l’Universite´ apres ` la fin sera a` la fois la seance solennelle de rentree ˆ de la guerre et la remise des diplomes aux 5 nouveaux docteurs. Je me ´ rejouis fort de cette occasion nouvelle de vous voir et vous adresse tous mes meilleurs compliments. Je vous communique inclus le projet de traite´ pour le livre que vous avez bien voulu me promettre,307 avec sans doute la collaboration d’un de vos ´ eminents compatriotes. Si vous voulez bien, vous me ferez part quand nous ´ nous verrons des observations ou modifications que vous auriez a` suggerer, ´ ´ en particulier en ce qui concerne la publication eventuelle d’une edition italienne. ´ Veuillez presenter mes hommages a` Madame Volterra et accepter ´ de ma bien cordiale amitie. ´ l’expression renouvelee Emile Borel
Hadamard to Volterra Paris, n.d. [December 1919] Mon cher ami, ´ emonie ´ A l’occasion de la cer qui nous vaudra le plaisir de nous voir le ´ ´ mission de vous inviter a` la 20 decembre prochain a` Paris,308 j’ai l’agreable ´ ´ le 21, a` 16h 1/2, rue de Poitiers, no 12, en votre reception qui sera donnee honneur et en celui des autres savants a` qui l’Universite´ de Paris a tenu a` ´ conferer le titre de docteur honoris causa. ˆ et, en vous Je suis heureux de pouvoir vous donner rendez vous a` bientot, ´ priant de vouloir bien presenter mes respectueux hommages a` Madame Volterra, vous serre cordialement la main J. Hadamard 305
Apart from Volterra, the other receivers of the Doctorate honoris causa that day were the British jurist Sir Frederick Pollock (1845–1937), Albert Brachet (1869–1930) professor of Anatomy and Embiology at the University of Brussels, the Danish philologist Kristoffer Nyrop (1858–1931), and H.G. Greenish (1855–1933), dean of the London School of Pharmacy (see Figaro, 21 December 1919).
306
See footnote 294.
307
The book in question may be a volume about dirigibles as Borel makes an allusion to it in a subsequent letter (29 April 1920). In fact, it seems that the book was never written or at least never published (see footnote 334).
308
See footnote 294.
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Volterra to Borel n.p., n.d. [December 1919] (draft of a telegram)
Emile Borel Vice Directeur Ecole Normale Rue Ulm Paris ` ´ Sinceres affectueux remerciements. Assisterai seance 20 Sorbonne.309 310 Arriverai mercredi 17 Lutetia. Volterra
Borel to Volterra Paris, 17 December 1919 Mon cher ami, ´ Pourriez vous me faire le plaisir de dejeuner avec moi vendredi 19 a` midi 1/2 au cercle de la Renaissance franc¸aise 12 rue de Poitiers. Si vous ´ n’etiez pas libre vendredi ou si vous arriviez a` Paris trop tard pour pouvoir ´ ´ eriez, ´ me repondre, nous pourrions, si vous pref choisir lundi prochain 22, a` ˆ ˆ la meme heure et au meme lieu. ` que le voyage ne vous aura pas trop fatigue´ et je vous prie J’espere ´ de mon affectueuse amitie. ´ d’accepter l’expression renouvelee Emile Borel
309 310
For a description of this event, see Figaro from 21 December 1919. See also footnote 305. See footnote 245.
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Borel to Volterra Paris, 2 February 1920 Mon cher ami, La librairie Alcan311 me charge de vous demander si le projet ci-inclus convient a` vous et a` votre collaborateur312 et si vous croyez pouvoir fixer une date pour la remise du manuscrit. ` international des mathematiciens ´ ˆ Le congres de Strasbourg va etre fixe´ ˆ l’avis officiel. au 22 septembre313 ; je pense que vous en recevrez bientot ` Les amis de l’Italie esperent vivement que les affaires politiques s’arrangeront rapidement; je crois que votre nouveau gouvernement sera ´ edent ´ meilleur que le prec en ce sens qu’il traˆıtera les questions au lieu de les laisser traˆıner.314 La Faculte´ des sciences de Paris a vote´ a` l’unanimite´ mon transfert dans ´ la chaire de physique mathematique; cela va me donner beaucoup de tra´ vail; je n’ai pas pu decider Langevin a` demander cette chaire315 .
311
See footnote 257.
312
See footnote 307.
313
After the creation of the International Research Council at the end of 1918, Picard, as president, had used all his strength during the Brussels meeting of July 1919 to assure that the first International Congress of Mathematicians of the after-war period would be organized in Strasbourg, newly freed from the German grip. The previous Congress had taken place in Cambridge in 1912, and the 1916 Congress, which was supposed to be in Stockholm, had been canceled because of the war. Picard’s coup de force at the International Mathematical Union had attracted heavy criticisms from delegates of neutral countries, and in particular from the unfortunate Mittag-Leffler who was reluctant to see the Stockholm congress escape. He was perhaps among those targeted as personnes timor´ees by Picard in his introductory address to the Strasbourg congress [56], p. XXXI. Picard’s anti-German obsession soon resulted in his gradual isolation after 1923. On this subject see [1], and Pierre Lamand´e: Un exemple de math´ematicien durant et apr`es la Premi`ere Guerre Mondiale in [22]. 314
January 1920 was a month of social crisis in Italy with two successive powerful strikes of post offices and railways. The head of the Italian Government, Francesco Nitti (1868–1953), had succeeded Orlando in June 1919 in the midst of foreign and domestic crises involving Italian territorial claims disputed by other Allied countries and the economic and fiscal problems created by the war and demobilization. Nitti adopted the system of proportional representation and succeeded for some months in keeping control of the equilibrium between Socialists, Christian Democrats and Popolari. At the beginning of 1920, his government soon became undermined by the strikes and the disorders fomented by Mussolini’s new Fascist party, and, after several ministerial crises, Nitti eventually resigned in June 1920, replaced by the elderly Giolitti (1842–1928). The reading of Italian newspapers (e.g. Corriere della Sera) gives a vivid picture of the intricate situation.
315 The exact name of the chair is Chaire de Calcul des Probabilit´es et de Physique Math´ematique. It had been created in the 1830s on the insistence of Poisson and occupied by many mathematicians (including Bertrand, Boussinescq and Poincar´e). The fact that Borel tried to convince Langevin to accept the position instead of himself is an interesting point as Langevin, one of his close friends of the group in L’Arcouest (see Charlotte Bigg’s paper in [22]), was clearly a Physicist and not a
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´ Veuillez presenter mes hommages a` Madame Volterra et croire toujours ´ ´ a` mes sentiments les plus affectueusement devou es. Emile Borel
Picard to Volterra Paris, 28 February 1920 Mon cher ami, Vous avez sans doute appris par M. Kœnigs316 que le Comite´ national ´ ´ ´ ´ franc¸ais de mathematiques, dont je suis president, a resolu, conformement ´ ´ aux decisions prises a` Bruxelles par l’Union mathematique internationale ` provisoire, de convoquer a` Strasbourg le 22 Septembre prochain un Congres 317 ´ aux savants ´ Les invitations, adressees international des mathematiciens. des pays de l’entente et des pays neutres, seront personnelles. Nous ne ´ e´ trop ostentenons pas a` inviter chez les neutres des personnes qui ont et siblement hostiles a` notre cause pendant la guerre. Je viens vous demander un service, en ce qui concerne l’Italie. Nous avons peur de commettre des erreurs ou de faire des oublis. Pourriez-vous charger quelqu’un de vos ´ eves ` ´ el ou amis de dresser la liste des mathematiciens italiens qui devront ´ , ˆ ´ Il s’agit, bien entendu, de mathematiques ´ pures et appliquees etre invites? ´ et il y aura aussi une section de physique mathematique. ´ M. Kœnigs vous a dit aussi probablement que nos comptons reunir ` des del ´ egu ´ es ´ des Comites ´ a` Strasbourg deux jours avant le Congres
mathematician (on Langevin, see also footnote 217). This decision of Borel (even if it was made without enthusiasm) had many consequences. By his acceptance, Borel definitely gave a mathematical flavor to the Chair by developing the teaching of probability theory. Borel’s relationship with mathematical probability has always been complicated: on one hand, he was convinced of the important role played by probability in modern science and in the scientific enlightment of the general public (leading to him writing his very popular volume Le Hasard [9] in 1914, which had several editions) but on the other hand, he had little consideration for it as a mathematical discipline (see [10] and [7]). Nevertheless, Borel’s important political position allowed the growth of probability theory in scientific academic life in inter-war France, in particular through the creation of the Institut Henri Poincar´e in 1928. 316
Gabriel Koenigs (1858–1931) was a French mathematician, who made important contributions to geometry and mechanics. He was professor of mechanics at the Sorbonne and was elected a member of the Acadmie des Sciences de Paris in 1918.
317
The International Mathematical Union (IMU) was founded on September 1920; however, the first steps towards its formation were taken in 1919 in Brussels at the Constitutive Assembly of the International Research Council. The Belgian mathematician Charles de la Vall´ee Poussin presided at the meeting. The IMU faded away in the years 1931–1936 and was revived after the World War II (1951). See [34].
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´ nationaux de mathematiques ou d’organes similaires pour fonder ´ ´ definitivement l’Union internationale de mathematiques. Ce sera, je crois ´ e´ en fait fondee ´ a` Bruxelles, et qu’il s’agira facile, puisque cette Union a et seulement d’adopter, avec les modifications que l’on jugera convenables, ´ les statuts provisoires etablis a` Bruxelles.318 ´ Nous esperons tous ici que vous pourrez venir a` Strasbourg. Je puis vous ´ ´ erale ´ dire a` l’avance que nous vous prierons de faire une Conference gen sur tel sujet qui vous plaira. ` bon hiver, et je ne me ressens plus des fatigues J’ai jusqu’ici passe´ un tres ´ e´ dernier. On m’a dit que vous aviez eu la grippe; j’espere ` que vous de l’et ˆ ` ´ etes completement remis, et que toute votre famille est en bonne sante. ˆ ´ Combien de temps faudra-t-il avant Le monde continue a` etre bien trouble. ´ ˆ ` que l’humanite´ retrouve son equilibre. Les gens de mon age n’osent guere ´ esperer vivre quelque jour dans des temps plus normaux, et ils doivent se ´ resigner a` une existence incertaine du lendemain. Veuillez, cher ami, nous rappeler, ma femme et moi, au souvenir de ´ ´ Madame Volterra, et croire a` mes sentiments affectueusement devou es, Emile Picard
Volterra to Picard Roma, n.d. [March 1920] (draft)
Societa` Italiana delle Scienze detta dei XL M. cher Ami, Je commence d’abord pour vous remercier de l’envoi que vous avez bien ´ ´ voulu me faire de la belle commemoration de Lord Kelvin qu’on avait publiee ´ ´ et. ˆ 319 J’ai donne´ mon adhesion a` et que j’ai relue avec le plus grand inter ` de Strasbourg. Il vous aura certainement Monsieur Kœnigs pour le congres ´ ´ evoqu e´ ce que je lui ai ecrit. Je serai heureux de me trouver a` Strasbourg pour prendre part aux ` et aux reunions ´ ´ travaux du Congres preliminaires. C’est avec le plus grand
318
The Draft Statutes of the IMU (International Mathematical Union) followed the general pattern of the IRC (International Research Council) and was approved by the participants of the Brussels meeting; see [52].
319
E. Picard, Notice historique sur la vie et l’oeuvre de Lord Kelvin, associ´e e´ tranger de l’Acad´emie: lue dans la s´eance publique annuelle du 22 d´ecembre 1919; Institut de France, Acad´emie des sciences, Paris, Gauthier-Villars et Cie, 1919.
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` ` plaisir que j’ai vu le choix de cette ville comme siege du prochain congres ´ des mathematiciens. Je suis heureux de pouvoir ainsi apporter mon hom` des luttes hero¨ ´ ıques a` la Patrie. mage a` cette ville Franc¸aise revenue apres ` honore´ de votre proposition de faire une conference ´ ´ erale ´ Je suis tres gen ` 320 J’accepte avec beaucoup de plaisir. Puisque vous me laissez au congres. le choix du sujet j’aurai l’honneur de le soumettre a` votre approbation d’ici ´ eves ` a` quelque temps. J’ai charge´ un de mes el de dresser une note de ´ ´ tous les professeurs de mathematiques, de physique et de mathematiques ´ de nos universites ´ et ecoles ´ ´ appliquees des ingenieurs, ainsi que des assistants et des professeurs libres (liberi docenti). J’y ai fait ajouter le liste des ´ e´ Mathem. ´ membres de la societ qui comprend la presque totalite´ des pro´ ´ fesseurs de mathematiques de nos institutions secondaires qui s’interessent ˆ sous peu et je vous l’enverrai tout aux questions scientifiques. Elle sera prete ` de l’Instruction Publique Italien n’a pas encore repris de suite. Le Ministere la publication des listes officielles des professeurs qu’on publiait jadis avant la guerre, c’est pourquoi quoiqu’on y ait mis tout le soin possible il y aura ´ quelques inexactitudes inevitables. ´ e´ malade pendant l’hiver de la grippe et ce n’est que depuis peu de J’ai et jours que j’ai repris ma vie habituelle. ` Je partage completement votre avis sur les question qui agitent dans ´ Helas, ´ ce moment l’humanite. c’est bien malheureux ce que nous voyons. Je crains qu’on n’oublie trop vite ce que nos ennemis nous ont fait souffrir ´ de guerre! pendant les longues annees
Volterra to Borel n.p., n.d. [April 1920] (draft) ´ e´ heureux d’apprendre que dans les derniers jours a` Nice il y a eu J’ai et ´ ´ une reception si cordiale entre le Prince de Udine qui etait alle´ a` la rencontre ´ ont de M. Deschanel.321 Nos deux pays par la voix de leurs representants ´ Je n’ai pas eu une nouvelle occasion d’exprimer leurs sentiments d’amitie. ´ eter ´ besoin de vous rep que je continue a` apporter a` cette amitie´ tous mes efforts.[?]
320
V. Volterra, Sur l’enseignement de la Physique math´ematique et de quelques points d’analyse, Congr`es International des Math´ematiciens, 24 Septembre 1920. Comptes rendus du Congr`es, pp. 81–97. 321
Paul Deschanel, president of The French Republic since January 1920, met the Prince of Udine, Vittorio Emmanuele’s cousin, in Nice on 5 April 1920. The mundane ceremony is described with pathos in the Corriere della Sera on 6 April 1920, but appears as a small diversion from the numerous contemporaneous papers emphasizing the difficult relations between Paris and Rome.
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` que vous serez bientot ˆ delivr ´ es ´ de tout souci pour les questions J’espere ˆ de d’Allemagne.322 Le militarisme allemand n’est pas abattu du tout il tache ˆ a` toute occasion. Les garanties ne sont jamais de trop et je relever la tete ´ n’ai aucune confiance dans ce qu’ils desirent faire encore. Je vous prie de vouloir bien accepter une photographie dans le costume ˆ a` la Sorbonne.323 que j’ai revetu ´ ` de Strasbourg et je compte d’y J’ai donne´ mon adhesion au congres 325 ˆ ´ ´ erale. ´ accepte´ de faire une conference gen Je serai aller.324 J’ai meme ´ ee ´ par tant fier de porter personnellement mon hommage a` la ville delivr ´ ıques. d’actions hero¨ ´ erales ´ Maintenant je m’occupe d’un travail sur les questions gen de ´ edit ´ e. ´ Des ` qu’il sera possible de pouvoir travailler avec M. Per ´ es ` pour l’her ` volontiers. Je puis dire que meme ˆ un ouvrage d’ensemble je le ferai tres ´ cela est ce que je desire le plus dans ce moment.326 M. Sartre327 travaille et ` forte [?] le dernier livre de M. de la Vallee ´ il nous a expose´ d’une maniere Poussin.328 ` de l’Instruction la question des echanges ´ ˆ ee ´ dans Au ministere est arret ´ les bureaux – et je ne puis rien faire a` ce propos. Je desire en parler avec le ´ nouveau ministre pour voir si on pourra faire la chose, mais pas cette annee, je crains qu’il n’est possible de porter la chose dans un terrain pratique.
322
Volterra probably alludes to the troubled situation Germany had experienced in March 1920 after Kapp and General von L¨uttwitz’s coup d’´etat attempt against Ebert’s government on 12 March. Ebert eventually succeeded in keeping control of the situation. 323
See footnote 309.
324
See footnote 313.
325
Volterra gave a general lecture in Strasbourg with title On teaching of Mathematical Physics and some points of Analysis, where he gave a broad picture of how functional analysis (in particular, his own functional calculus) had become an important tool in Physics.
326
See ♥ 7 (note 366).
327
Louis Sartre (1891–1971) entered the Ecole Normale in 1911. In his obituary (Association Amicale des Anciens El`eves de l’Ecole Normale Sup´erieure, 1973; pp. 59–62), it is mentioned that he became prisoner during the battle of Charleroi (see footnote 21), and remained in captivity for the whole war. The authors of the obituary insist on how WW1 remained a very traumatic period for Sartre; they describe his permanent anxiety and revolt. Following [13] (p. 76), Sartre was for a while secretary of the S´eminaire Hadamard during the 1920s, and advised Chˆatelet to give an account of the theory of ideals at the seminar. Following the official results of the Agr´egation, Sartre passed the Agr´egation at the special Fall session organized for students who had not been able to sit because of the mobilization. Sartre however later chose a career in companies of electrical energy. He became director of the Compagnie de distribution d’´electricit´e and of the Laboratoire central des industries e´ lectriques. 328 Volterra probably refers to the book Lec¸ons sur l’approximation des fonctions d’une variable r´eelle, published by Gauthier-Villars in 1919.
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Borel to Volterra Paris, 29 April 1920 Mon cher ami, 329 ´ ` ´ Votre portrait est un don precieux qu’il me sera particulierement agreable d’avoir dans mon cabinet de travail ou` il me rappellera de lointains et ´ ´ ` et solide amitie. ´ agreables souvenirs et sera un temoignage d’une fidele ´ J’ai pris la resolution de quitter la sous-direction de l’Ecole Normale ou` ´ j’etais de plus en plus absorbe´ par le travail administratif330 ; c’est M. Ves331 siot qui me remplacera. Nous habiterons, a` partir du 1er mai: rue du Bac, 32, Paris VII, dans l’appartement que quitte M. Appell, qui va habiter la Sorbonne.332 D’autre part, je pars le 11 mai avec Painleve´ pour une mission en Chine, ´ a` affermir nos relations intellectuelles avec la Chine; je pense que destinee nous rentrerons en octobre. Nous allons par San Franscisco et reviendrons par Suez.333 ´ Je vous remercie d’avoir pu trouver un collaborateur qui pourra ecrire le livre sur les dirigeables. M.Toussaint,334 qui a remplace´ M.Maurain a` la ´ Direction de l’Institut de St Cyr, ecrira le livre sur l’aviation. 329
See the previous letter.
330
Camille Marbo in her book [39] gives another, and more reliable, explanation for Borel’s decision. Borel told her that he could no more bear the atmosphere of the school in mourning because of the huge casualties of the war. See for instance L. Mazliak: Les fantmes ˆ de l’Ecole Normale in [22].
331
Ernest Vessiot (1865–1952), French mathematician, was a specialist of the representation of Lie groups. During the war, Vessiot had made important ballistic studies.
332 Appell, Borel’s father in law (see footnote 12), had been appointed Recteur of the University of Paris district in 1920. 333 According to Camille Marbo’s memoirs, China asked France to send a delegation of specialists in several domains ([39], p. 172). The reality was slightly more intricate, as France was anxious to consolidate its positions in the Far East in front of British and American interests. On Painlev´e’s mission to China, see Marianne Bastid-Brugui`ere: Le voyage en Chine de Paul Painlev´e en 1920, in [16] (pp. 83–103). One may also read with interest an article in the New York Times from 28 May 1920 M. Painlev´e arrives on mission to China, illustrating the growing tension between France and USA around the Peace treaty. 334
Albert Toussaint (1885–1956), born Belgian, was asked before the war by Painlev´e to become the technical director of the new Aerotechnical Institute of Saint-Cyr (IAT) at the side of the director Charles Maurain. In 1914, the STAM (technical section for military aeronautics) asked him to establish a method to realize on-flight essays to determine several parameters such as altitude, inclination and relative speed. In 1919, the STAM decided to place the IAT under the under secretary of state for aeronautic and proposed the direction to Toussaint. Toussaint defended a thesis in Physics in 1923. The book L’aviation actuelle was published in the Nouvelle Collection Scientifique of Borel only much later in 1928. In his preface of the book, Ch. Maurain explains that Toussaint’s new responsibilities did not leave enough time to finish the book before. In 1930, Toussaint obtained a position at the University of Paris and at the Conservatoire des Arts et M´etiers as professor of aeronautic technique. On Toussaint, see [17], pp. 607–609. On the contrary, we
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` grand regret de ne pas etre ˆ ` de J’aurai le tres rentre´ pour le congres Strasbourg; je n’ai pas besoin de dire combien je suis heureux de votre ´ participation, qui lui donnera beaucoup d’eclat; je pense que vous pourrez ´ es. ` vous entendre avec Per ` que les echanges ´ J’espere universitaires finiront par aboutir; en France, ` du ministre M. Honnorat335 vous auriez en ce moment toute facilite´ aupres qui aime beaucoup l’Italie et a pris M. Luchaire336 comme chef de cabinet. Merci beaucoup pour M. Sartre.337 ´ Presentez, je vous prie, mes hommages a` Madame Volterra et acceptez ´ l’expression de mon plus affectueux devouement. Emile Borel
Volterra to Borel n.p., n.d. [May 1920] (draft) Mon C.A. Je viens de recevoir votre aimable lettre par laquelle j’apprends que vous avez quitte´ la sous-direction de l’Ecole Normale Sup.338 Pendant les ´ ´ ´ annees que vous avez passees dans cet etablissement vous avez exerce´ ´ une influence considerable sur la jeunesse franc¸aise et l’importance des
could not find any information on the mentioned book about dirigibles. Maybe the project had been eventually canceled. 335 Andr´e Honnorat (1868–1950) was a typical civil servant of the French IIIrd Republic. During his long career he worked with numerous governments. As a deputy belonging to the radical movement, he presented several pieces of social legislation, in particular for improving the education of people suffering from tuberculosis in order to prevent communicating the infection. Honnorat gave also in 1919 the original impetus for the creation of the Cit´e Internationale in Paris, a place offering accomodation to foreign students. In 1920, when Millerand became Prime Minister, he called Honnorat to become minister of Public instruction. Luchaire, in his memoirs (see footnote 336) has many laudatory comments about Honnorat. It is worth mentioning that in 1940, Honnorat was one among the 80 deputies who refused to attribute unlimited powers to P´etain. An important act of Honnorat’s term as minister was to charge the young historian Pierre Renouvin with the mission of explaining the causes of the war. This had very large consequences on French historiography of the First World War. See Honnorat’s biography on the Institut Pasteur website http://www.pasteur.fr/infosci/archives/hon0.html and J.-B. Duroselle: Pierre Renouvin, in Encyclopedia Universalis, 2007. 336
On Luchaire, see footnote 100. When Honnorat (see footnote 335) became minister of Public Instruction, he asked Luchaire to be his Chef de Cabinet. See in Luchaire’s memoirs [37] his lucid comments on Honnorat’s political activities. pp. 57–68.
337
See footnote 327.
338
See footnote 330.
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´ ´ eves ` resultats que vous avez obtenus se manifeste dans les jeunes el (qui ` scisont maintenant des maˆıtres) que vous avez guide´ dans la carriere entifique. Votre nouvelle fonction a` la Sorbonne comme Pr[ofesseur] de ´ ` large Ph[ysique] mat[hematique] vous donnera maintenant un domaine tres ´ ou` vous pourrez exercer une enorme influence dans la science et dans l’enseignement.339 ´ e´ recteur de C’est par votre lettre que j’ai appris que M. Appell a et l’Universite´ de Paris.340 Ici dans ce moment de crise ou` les journaux ne ´ ` paraissent pas reguli erement et ne donnent que peu de nouvelles on n’est pas au courant de ce qui se passe. Je suis heureux de la haute position que ´ M. Appell s’est conquise par ses grands merites. Je suis sur ˆ qu’il va jouer un ˆ dans l’enseignement en France. La France, en mettant [?] dans grand role ´ d’administration les mains d’un si grand savant qui a montre´ des qualites ´ ´ si etonnantes l’organisation de ses instituts d’ instruction [?] et d’education ˆ peut etre sure de son avenir. Je n’ai pas besoin de vous dire que je souhaite a` vous et a` M.P. un bon ` dans les pays lointains ou` vous allez.341 Je voyage et le meilleur succes serais heureux de pouvoir faire un aussi beau voyage. Le dernier que j’ai ˆ fait en Californie m’a donne´ l’envie d’aller dans l’extreme Orient. Lorsque ´ ´ j’etais a` S. Francisco j’etais quelque honteux de ne pas connaˆıtre la Chine ´ si frequemment ´ et le Japon qui sont visites par les amoureux du Far West. Je crois que l’Europe doit continuer le plus possible ses rapports avec ces pays. [The two following sentences are typed on a new page and it is not clear that they belong to the same letter] Je suis heureux d’apprendre que vous n’avez pas d’objection aux condi` lettre par rapport au livre a` tions que je vous soumettais dans ma derniere publier. J’en parlerai a` Monsieur Bianchi.342 ´ Je vous prie de vouloir presenter mes hommages a` Madame Borel. ` et affectueuse amitie´ et Veuillez accepter l’expression de ma plus sincere ´ de tout mon devouement.
339
See footnote 315.
340
See footnote 332.
341
See footnote 333.
342
On Bianchi, see footnote 349. The book mentioned may be the project cited in footnote 334.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
Picard to Volterra Paris, 9 June 1920 Mon cher ami, ´ Nous comptons sur vous pour faire une conference a` Strasbourg sur tel ´ a` me donner par avance sujet qui vous conviendra. Vous avez bien voulu dej ´ votre acceptation, et tous les mathematiciens franc¸ais vous en remercient. ´ ´ Nous esperons que de nombreux mathematiciens italiens viendront au ` Je crois qu’on y verra surtout des Belges, des Italiens et des Congres. ´ Franc¸ais. Il parait que l’epoque est peu favorable pour les Anglo-Saxons. ` c’est-a-dire ` Vous vous rappelez que deux jours avant le Congres, le lundi ´ ´ egu ´ es ´ pour la fondation definitive ´ 20 Septembre, il y aura des reunions de del ´ ´ ´ a` Bruxelles.343 Vous y representerez de l’Union mathematique, esquissee ˆ ` sans doute l’Italie, peut-etre avec quelques collegues. ´ ´ il y a quelque temps, une correspondance avec l’Academie ´ J’ai echang e, ´ ´ de Naples, a` titre de President du Comite´ executif du Conseil international ´ se plaignait de ce que dans les Unions de recherches.344 Cette Academie ´ elle n’avait pas de representants ´ fondes dans les commissions. Je lui ai ´ ´ repondu qu’elle pouvait me faire connaˆıtre ses desirs a` ce sujet, et que je ´ executifs ´ les transmettrai aux Comites des Unions, qui y donneraient cer` que vous m’approuverez de cette initiative. tainement satisfaction. J’espere ´ Je n’ai pas voulu faire attendre trop longtemps ma reponse: aussi avais´ je seulement ecrit a` Lecointe.345 Croyez, mon cher ami, a` mes sentiments ´ ´ d’affectueux devou ement Emile Picard
343
See note 317.
344
The Academy of sciences of Naples has its origin in the late 17th century – when the Accademia Palatina (1698) and then the Accademia delle scienze (1732) were instituted. Later on, after several changes and transformations, the new Societ`a reale borbonica (1816) was founded, which split after 1861 into three academies: the Academy of moral and political sciences, the Academy of Archeology, letters and arts, and the Academy of mathematical and physical sciences, which Picard refers to. See [40].
345
Georges Lecointe (1869–1929) was appointed director of Royal Belgian Observatory. He was a physicist, official and explorer; he was the chief of staff of the voyage Belgica to Antartic (1899) and wrote many scientific reports on this voyage. He was a member – together with V. Volterra and G. Hale (Director of the Observatory of Mount Wilson, Pasadena, California) – of the International Research Council (President: E. Picard; general secretary: A. Schuster).
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Volterra to Picard Roma, 12 July 1920 (draft) Mon cher ami, ´ ` de Strasbourg et Comme je vous ai ecrit je ne manquerai pas au Congres ` ´ je serai heureux et tres-fier d’y faire une Conference dont je vous donnerai ´ le sujet. J’arriverai aussi deux jours en avance pour l’Union Mathematique. ´ Je ne sais pas combien de mathematiciens Italiens pourront venir aussi, ´ et des depenses ´ mais je crains a` cause des difficultes des voyages que ˆ ` qu’un certain nombre le nombre n’en pourra etre grand. Toutefois j’espere ` ˆ viendra a` Strasbourg. On voyage maintenant tres-peu chez nous et meme ´ e´ dans les derniers temps assez difficile a` cause la correspondance a et ` ´ des postes.346 Nous ne sommes pas encore a` des greves des employes ´ Depuis presque un mois les tramways des environs ne bout des difficultes. marchent pas c’est pourquoi nous n’avons pas encore abandonne´ la ville pour Albano. ´ ´ L’Academie des Lincei est maintenant l’Academie nationale, ce qui a ´ e´ consacre´ dans le nouveau statut et adopte´ par le gouvernement il y et a quelques mois.347 ´ ´ Ne pensez-vous qu’il serait utile de reunir le conseil executif s’il y avait ´ quelque question a` mettre a` l’ordre du jour? J’en ai ecrit aussi a` M. Schuster. Veuillez accepter, mon cher Ami, l’expression de ma plus haute estime et ` et affectueux devouement. ´ de mon sincere
346
From January to July 1920 the newspaper Corriere della Sera reported several different strikes in Italy – strikes of the Post, Railways, and civil servants in general. A long and hard economic crisis began which led many Italian workers to emigrate abroad (mainly to other European countries and to America). 347
During the second semester of 1920, the Accademia dei Lincei became indeed a truly National Academy. Volterra possibly played an important role in the recognition of the Academy, since in the meantime he was elected vice-president of the Academy in place of the physicist Antonio Roiti (1843–1921).
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Picard to Volterra Abbadia,348 , 1 August 1920 Mon cher ami, ´ Je me rejouis de vous voir a` Strasbourg le mois prochain. Je suis ´ ´ heureux de savoir que l’Academie des Lincei est maintenant votre Academie ´ nationale. J’ai eu une correspondance, tout juste aimable, avec l’Academie de Naples qui a proteste´ parce que certains savants italiens n’avaient pas ´ e´ introduits dans les Commissions des Unions astronomique et et ´ geophysique. J’ai demande´ alors la liste de ces savants, en disant que le ´ Comite´ executif la communiquerait aux Bureaux des Unions,349 qui seraient ˆ juges de ce qui pouvait etre fait. Le mieux est, je crois, de se montrer ´ ˆ conciliant dans cette affaire pour eviter des scissions qui pourraient etre ´ dangereuses, alors que certains neutres desirent toujours au fond reprendre des relations avec les Allemands dans nos diverses Unions. Je vous ´ e´ envoyee ´ par le secretaire ´ ´ transmets la liste qui m’a et de l’Academie Napolitaine.350
348
The explorer Antoine d’Abbadie (1810–1897) bequeathed a castle he owned near Hendaye to the Paris Academy of Science. The castle is still owned by the Academy, where cultural activities such as exhibitions or concerts take place.
349
The International Research Council was composed by National Committees. The Italian Committee was organized as follows: President: V. Volterra; Members: A. Abetti, Director of the Astronomical Observatory of Arcetri, Florence; N. Vacchelli, Director of the Military Geographical Institute, Florence; V. Cerulli, President of the National Committee of Astronomy, Rome; C. Somigliana, President of the National Committee of Geodesy, Turin; General secretary: G. Magrini, Director of the Hydrographical Office, Venise; secretary for Astronomy: G. Abetti; E. Bianchi, Director of the Observatory of Brera, Milan; G. Zappa, Director of the Observatorio of the Collegio Romano, Rome; G. Platania, professor of physical Geography and Vulcanology, Catania. See also the following note.
350
The list, which Picard refers to, is not contained in the Volterra Archive. It should be almost the same as the list drafted by Volterra in the following letter. On the discussions about the choice of Italian astronomers in International conferences, Boccardi wrote a furious passage in the letter quoted above in ♦ 5: “ In Brussels (July 1919) the International Astronomical Union was founded, and around twenty specialized commissions were organized, they were filled by young astronomers, assistants, simple doctors etc.; but they took a special care not to include me in any commission, even in the commission for Ephemerides, though I am the only Italian who edits an ephemeride and since 1911 realizes a considerable part of the international work shared between 5 institutions Paris, Greenwich, Washington, Turin, San Fernando! I was excluded on purpose from the Commission of the variations of latitude, though in 1916 I obtained a Prize from Paris Academy of Sciences for my researches on this variation. As my French colleagues complained to M.M. Picard, Baillaud, etc. about the situation, these gentlemen agreed that they had organized the affair badly because they thought that the Academy Lincei was the only representative of science in our country. In Strasbourg, M. Picard repeatedly told me that everything was going to be fixed; but up to now, nothing is done.”
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Je suis, depuis quinze jours, a` Abbadia avec ma famille. J’y resterai ´ jusqu’au 4 Septembre. J’ai ecrit a` Schuster au sujet de votre suggestion ´ ´ d’une reunion du Comite´ executif. Bien cordialement a` vous Emile Picard ˆ ´ ` Hagen.351 Peut-etre J’ai fait des reserves au sujet de la nationalite´ du pere pouvez-vous savoir quelque chose a` ce sujet.
Volterra to Picard n.p., n.d. [August 1920] (draft) Mon cher Ami, Je sais que Ricco` et Raina avaient l’intention d’ajouter quelques noms ´ esique ´ ´ dans les commissions de l’Union Geod et Geographique. Malheureuse` les renseignements que j’ai ment ils sont morts tous les deux.352 D’apres ` bien rec¸u il va tres
351
Johann Georg Hagen (1847–1930) was born at Bregenz on Lake Constance in the western tip of Austria. In 1863 he entered the Jesuit order in Gorheim, southern Germany. He studied astronomy and theology at the Universities of M¨unster and Bonn. In 1872 Bismarck decreed the expulsion of the Jesuits. Hagen went to England and in 1880 to the United States (Prairie du Chien, Wisconsin). In 1888, he was appointed director of the Observatory of Georgetown College, Washington. In this period, he became an American citizen. In 1906, he became the director of Vatican Observatory. He published many papers and works of astronomy and mathematics. 352 This sentence was added afterwards. Annibale Ricc` o (1844–1919) studied in Milan and Modena. In 1878 he was appointed professor of physics at the School of Engineers of Naples and two years after at the University of Palermo, where he also worked at the astronomical Observatory. In 1890 he was asked to move to the University of Catania as professor of astrophysics and became director of the Observatory on Mount Etna as well as the first director of Catania Observatory. He published important works in astronomy and geophysics; he also served as vice president of the International Astronomical Union. Michele Rajna (1854–1920) studied at the University of Pavia and was a student of Giovanni Schiaparelli at the Observatory of Milan. In 1903 he was appointed professor of astronomy at the University of Bologna, where he also directed the local Observatory. His main researches concern geodetic astronomy and terrestrial magnetism. Rajna died on September 1920.
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Volterra’s Exchanges with Borel, Hadamard and Picard in World War One
` Cometes – Louis Camera353 ´ erides ´ Ephem Etoiles Boccardi354 355 Calendrier Cardinal Maffi ´ Catalogues d’etoiles Angelitti356 Histoire de l’Astronomie ´ Magnetisme terrestre Alessio357 Pesanteur Etoiles variables Paci358 Je crois qu’il ne serait pas bien de placer Boccardi dans les variations des ´ latitudes ni dans la deviation de verticale. Je crois qu’il sera content d’entrer dans les commissions ci-dessus. ` Hagen, il est ne´ a` Bregenz dans le Vorarlberg qui apparteQuant au Pere nait a` l’ancienne Autriche. C’est ce qu’on lit dans les documents ´ biographiques. J’ai entendu dire qu’il est citoyen americain. Cette nature n’est pas facile a` contester car il ne ressort pas du gouvernement Italien, mais du Vatican.359 Je ne le connais pas personnellement mais parmi les ´ astronomes de Rome il a beaucoup de reputation et on le regarde avec une ´ ´ esiens ´ grande consideration. Il y a aussi des jeunes astronomes ou geod qui
353
Luigi Carnera (1875–1962) graduated in mathematics from the University of Pisa and then worked as assistant astronomer at the Astronomical Observatory of Turin; from 1900 to 1903 he worked at the Observatories of Heidelberg and Strasbourg. When he came back to Italy he worked at the Astronomical Station of Carloforte and, after a period of work in Argentina, became professor of astronomy at the Hydrographical Institute of the Navy in Genoa. From 1919 to 1932 he was director of the Astronomical Observatory of Trieste; then he became director of the Observatory of Capodimonte. He was a classical astronomer who made many observations and actively worked for the International Service of Latitudes.
354
Giovanni Boccardi (1859–1936) was ordinated priest in 1884. He taught mathematics in many schools of his congregation in Italy and abroad. He went to Rome (at the Specola Vaticana) where he improved his knowledge of astronomy and then to the observatories of Paris and Berlin. He taught astronomy at the University of Turin from 1903 to 1923. In 1906 he founded the Italian Astronomical Society and the related journal Rivista di astronomia e scienze affini. He published about 300 papers and various books of astronomy – both scientific and popular books. See also Boccardi’s letter to Fr´echet in ♦ 5 . 355
See footnote 137.
356
Filippo Angelitti (1856–1931) graduated in mathematics and engineering at the University of Naples; he worked at the Observatory of Capodimonte as a calculator and then as assistant astronomer. In 1897 he was appointed Director of the Astronomical Observatory of Palermo. His mainly researched on celestial mechanics.
357
Alberto Alessio (1872–1944) was a specialist in geodetics and gravimetry. Between 1907 and 1909, he sojourned at the Prussian Geodetics Institute and obtained the chair of Astronomy and Geodetics at the Hydrographical Institute of Genoa.
358
Ernesto Paci (1877–1937) graduated in mathematics from the University of Palermo in 1905. He became assistant astronomer at the Observatory of Palermo (1905–1913) and then at the Observatory of Catania (1913–1921). Afterwards he taught mathematics at secondary schools of Palermo and Catania. He published several works on observations of variables stars.
359
See note 352.
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´ e´ oublies ´ et qu’il serait avantageux de placer dans quelques comavaient et ` missions. Voici leurs noms: Cometes Zappa de l’Observatoire de Collurania Da Schio Padoue Pesanteur Cassinis Rome ´ Astronomie meridienne ViaroPadova ` avoir et ´ e´ malade pendant des annees. ´ 360 Celoria vient de mourir apres 361 ´ de la mort de Schiaparelli, nous avons perdu nos Depuis 1910, annee
360
Giovanni Zappa (1884–1923) studied physics at the University of Rome, where he graduated in 1906. He was assistant of Elia Millosevich at the Observatory of Collegio Romano in Rome and then astronomer in Catania (1910) and in Naples (1913). In 1917 he was appointed director of the Observatory of Colluriana (Teramo) and in 1912 became director of the Observatory of Collegio Romano – though he remained also director of the Observatory of Colluriana. He researched in astronomical refractions and questions related to the general theory of relativity. Almerico Da Schio (1836–1930) graduated in law from the University of Padua in 1860 and then worked, as assistant astronomer, at the Observatory of Padua from 1860 to 1865. In 1865 he was appointed director of the Meteorological Observatory of the Accademia Olimpica of Vicenza. He mainly researched on meteorology, but also on aeronautics. In 1905 he projected and constructed the aeroship Italia. Gino Cassinis (1885–1964) studied engineering and taught at the School of Engineers in Pavia; he then became professor of topography at the Polytechnic of Milan, whose he would have been rector. He was also General Secretary of the National Committee of Geodesy and Geophysics of CNR (National Research Council). He researched in geodesy and geophysics. Bortolo Viaro (1870–1922) studied sciences at the University of Padua, where he graduated in 1893. Then he studied astronomy in many observatories; he was astronomer at the Observatories of Arcetri (1894–1914), Padova and Catania (1920), where he was director of the Observatory and professor of astronomy at the University. He wrote about 50 papers on various astronomical issues. Giovanni Celoria (1842–1920) studied at the University of Turin and all his life was astronomer at Brera Astronomical Observatory in Milan, directed by Schiaparelli. In 1900 he became director of the Observatory. He was also professor of geodesy at the Polytechnic of Milan and in 1902 was appointed president of the Italian Geodetic Committee. He was member of various academies and senator of Italy.
361
Giovanni Virginio Schiaparelli (1835–1910) studied at the University of Turin and Berlin Observatory. He worked for over forty years at Brera Astronomical Observatory, whose he was director for a long time. Beginning in 1877 he believed he had observed long straight features in Mars, which he called channels (canali in Italian). Many decades later these channels of Mars were shown to be an optical illusion. He was member of many Academies and also elected Senator.
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362 ´ esiens. ´ ` meilleurs astronomes et nos geod C’est une situation tres douloureuse! Je resterai dans ma ville d’Ariccia jusqu’au mois de Septembre au moment ´ de mon depart pour Strasbourg. Je serai heureux de vous y revoir. ´ Veuillez presenter mes hommages a` Madame Picard et a` toute votre famille et veuillez accepter, mon cher Ami, l’expression de toute mon estime ´ et de tout mon devouement
Vito Volterra
362
In a previous draft, Volterra wrote: “In Italy, we have a crisis for Astronomy. Since 1910, the year when Schiaparelli passed away, our best astronomers died Fergola Lorenzoni Ricc`o Tringali etc. and almost all our geodeticians ave also died. We have the observatories of Rome Milan Catania without directors. Rajna from Bologna must often remain in a hospital. Almost all our Chairs for Geodetic science are vacant.” Emanuele Fergola (1830–1915) entered the Observatory of Capodimonte (Naples) as a student when he was only thirteen. He worked there all his life. From 1860 onwards, he was also professor of Analysis at the University of Naples. He published on pure mathematics (Bernoulli’s numbers, series, . . . ) and on astronomy (calculations of orbits, differences of longitudes, . . . ). He was a member of the Academy of Lincei; in 1905 he was elected Senator. Giuseppe Lorenzoni (1843–1914) was professor of astronomy at the University of Padua from 1872 to 1913. He was also director of the Astronomical Observatory of Padua. He published more that hundred works on celestial mechanics, geodesy, meteorology, spectroscopy, and astronomy. He was a member of the Academy of Lincei. Mangano Emanuele Tringali (1867– 1916) graduated in physics from the University of Catania and was assistant astronomer at the Observatory of this town. In 1898 he moved to the Observatory of Collegio Romano where he became astronomer. His main researches and publications concern spectroscopy.
Chapter ♥ 7
The Case of P´er`es
Joseph P´er`es (1890–1962) was a singular case among the French mathematicians who have experienced the troubled years of WW1. For almost every young man of his generation, the war became a key moment whose consequences have influenced them during their whole life. The war had been fatal for Gateaux. It left its permanent mark on Julia, horribly wounded in 1915. For many others, such as Fr´echet, L´evy or Chˆatelet, it caused deep changes in their careers. But P´er`es seemed to have crossed the period not only unharmed, but more surprisingly almost without noticing what was going on around him. Of course, this view is somewhat simplistic and we shall see how in his letters to Volterra he made several comments on a war he could not completely ignore. However, it seems that the key-moments of his life were organized without taking into account the ongoing events. At the beginning of their careers, P´er`es’ and Gateaux’s scientific lives proceeded much in parallel (see L. Mazliak: Les fantˆomes de l’Ecole Normale, in [22]). Like Gateaux, P´er`es had been a student at the Ecole Normale since 1908. In 1912, he passed the Agr´egation competition where he ranked second. The same year, he obtained a grant from the David Weill foundation (as Gateaux the year after) to go to Rome for a one year stay with Volterra. Borel seems to have had a high opinion of his potential. In a letter he sent to Volterra in 1913 for supporting Gateaux’s project to go to Rome, he informed his colleague that the latter was certainly less distinguished than P´er`es. P´er`es’ extraordinary luck was to have been exempted from military service in 1914. On 4 November 1914, Borel mentioned the fact in his letter to Volterra and told his Italian colleague that P´er`es had been appointed teacher at a secondary school in Montpellier, in the south of France. Unfortunately, we were not able to obtain details about P´er`es’ exemption since there is no military dossier in the military archives. At the beginning of the war, the rule was to send back the file of exempted men to civilian administrations. Up to now, we have not been able to locate P´er`es’ file. Some weeks later, he married, and the next year got his first child and defended his thesis (DOCUMENTS ♣ 1–♣ 2). He then began to deeply study the theory of permutable functions on which he was going to build his future career. Contrary to almost everyone of Volterra’s correspondents (at least among those we have
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followed up), P´er`es went on writing about mathematics. He submitted papers (9 were published during the war), several of them to the Rendiconti of the Accademia dei Lincei, communicated by Volterra. In a note to the Lincei from 1910,363 Volterra introduced a concept of composition and permutation of functions as a new tool for studying some integrodifferential equations. For F1 (x, y) and F2 (x, y) two real valued continuous functions, the composition of first kind of F1 and F2 is defined by ∗
∗
y
F 1 F 2 (x, y) =
F1 (x, ξ )F2 (ξ, y)dξ,
x
while the composition of second kind of F1 and F2 is defined by
∗∗ ∗∗
1
F 1 F 2 (x, y) =
F1 (x, ξ )F2 (ξ, y)dξ,
0
In general, the two previous operation are not commutative. Two functions sat∗
∗
∗
∗
∗∗ ∗∗
∗∗ ∗∗
isfying F 1 F 2 = F 2 F 1 (resp. F 1 F 2 = F 2 F 1 ) are called permutable of the first kind (resp. permutable of the second kind). In his lectures at Paris University in 1912,364 transcribed by P´er`es, Volterra extended his previous results and presented a first general study of the permutable functions of the first kind (Chapters IX and XI). In 1916 appeared a Memoir at the Academia dei Lincei,365 the only important mathematical paper Volterra published during the war period. It was besides completed by November 1914. In this long paper (83 pages), Volterra presented a general theory of powers, logarithms and more general functions of a function in the algebraic structure defined by the operation of composition. P´er`es received the paper and decided to follow up. He politely wrote to Volterra about his intentions (DOCUMENT ♣ 3), and began to work over the subject. He submitted several notes to Volterra for a communication to the Lincei (DOCUMENT ♣ 4). At the end of the conflict, P´er`es, who could count on an important list of scientific works, began his meteoric ascension in the Academic world. Having obtained a position at the University of Toulouse, he remained there only for some months. P´er`es himself had sent a letter to Volterra on 25 December 1918, in which he told him that most probably he would obtain a position in the Science Faculty in Toulouse, vacant after Samuel Latt`es’ death. P´er`es mentioned that he was very glad because a university position would give him more free time for mathematics than working in a Lyc´ee, though this would imply an important reduction of his salary.
363
V. Volterra: Questioni generali sulle equazioni integrali ed integro-differenziali, Rendiconti Accademia Lincei, 20 febbraio 1910.
364
V. Volterra: Lec¸ons sur les fonctions de lignes, Recueillies et r´edig´ees par Joseph P´er`es, Gauthier-Villars, 1913. 365 V. Volterra: Teoria delle potenze, dei logaritmi e delle funzioni di composizione, Memorie della R. Accademia dei Lincei, Vol. XI, Ser. 5, 1916.
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He interestingly added that he would leave Montpellier without regret, a somnolent town except for viticulture. This seems quite a contrast with what he had said at his arrival in Montpellier: almost exactly 4 years before, on January 25th, 1915, P´er`es wrote to Volterra: “Montpellier is a very pleasant city. The university life is rather intense”. Of course, these last lines were written just after the news of his definitive freeing from the army, obviously a considerable relief in 1915, and also after the happy occasion of his wedding. Nevertheless, his impatience to leave the town in 1918 for a better visible mathematical position is also the sign of a scientific ambition made possible by his mathematical works during the war. P´er`es was chosen in 1919 to join the University of Strasbourg, newly returned to France. The French Government wanted to make a display of French science from Strasbourg university. On that theme, see [28] and the references in the paper. This particularly stimulating environment proved efficient for P´er`es’ work. As it had been the case in Toulouse, P´er`es did not stay for long either in Strasbourg. In 1921, he was nominated full professor in Marseilles. In 1924, P´er`es and Volterra published a joint work, a book366 about the general theory of composition which includes all the previously mentioned results. Volterra alludes to the preparation of this book in a letter to Borel (see footnote 326). Later on, P´er`es came back to Paris as professor at the Sorbonne. Ironically, the war periods were fortunate for P´er`es; in 1942, he was elected to Paris Academy of Science. Subsequently, he became the dean of Paris University and played an important rˆole in the improvement of this institution, in particular as a promoter of a new scientific center in Orsay. The relationship between Volterra and P´er`es was more than a mathematical affinity. The year after he was in Rome, Volterra entrusted P´er`es with the transcription of the lectures he gave at the Sorbonne (see footnote 364 above). After the war, this proximity increased, as it is proved by the importance of the correspondence kept at the Lincei. They wrote the aforementioned book Lec¸ons sur la composition et les fonctions permutables, and another one in 1936 Th´eorie G´en´erale des Fonctionnelles. The latter was only the first part of the planned treatise, but Volterra’s troubles with Mussolini’s regime after the proclamation of the racial laws in 1938 followed by his death two years later did not allow the authors to publish the second part. In 1960, when a great meeting was organized in Rome to commemorate the centenary of Volterra’s birth, P´er`es was the main foreign speaker invited and he exposed his deep gratitude for his old master.367 If the war recurrently appears in the 24 letters of the war period, it is generally in a quite formal way, with the well polished words of the Union sacr´ee brainwashing, even when P´er`es evokes the casualties. He is clearly far away from the battle fields. This was also due to his very concrete geographical situation: Montpellier, a lovely city on the shore of the Mediterranean sea, was probably not the exact place where
366
V. Volterra et J. P´er`es: Lec¸ons sur la composition et les fonctions permutables, Gauthier-Villars, 1924.
367
Vito Volterra, nel primo centenario della nascita 1860–1960, Acc. Lincei, Roma, 1961.
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everything reminded you about the slaughter that was happening at this moment. The only slight exception in this strange detachment is to be found during the summer of 1917, when P´er`es mentioned to having realized computations of trajectories for the ministry of inventions. Sometimes, P´er`es seems so remote from the tragedy that his lightliness is staggering. That is the case when in January 1915, he seems relieved because he has more free time for his mathematical research as most of his students had been recently sent to the front. Or when in November 1916, he writes to Volterra with a confounding ingenuousness : “Are you still traveling with dirigibles? I think indeed that there are few means of transport more pleasant than this one”. We do not know how Volterra took P´er`es’ clumsiness. To say the least, it shows a striking contrast with Volterra’s engagement, an engagement which could lead him to tell to his wife: “What a pity our sons are not yet old enough to go to war” ([23], p. 180). However, in his answers, the Italian mathematician did not reproach P´er`es for anything. Perhaps after all he was satisfied to see that ordinary life was going on at least for some people of the young generation. P´er`es’ behaviour is certainly partly explained by his character. However, another reason may have been a question of survival; in a time so hard, with so many bereavements occuring every day around you, with so many casulaties among the young people you were frequenting during your studies, it is perhaps a necessity to adopt an attitude of withdrawal.
Document ♣ 1 P´er`es to Volterra . Montpellier, 25 January 1915 Monsieur et cher Professeur, ˆ ´ Je m’excuse d’etre reste´ aussi longtemps sans vous ecrire et en parˆ ´ ticulier d’etre aussi en retard pour vous presenter mes meilleurs vœux ´ Mais il faut en rendre un peu responsables les pour la nouvelle annee. ´ circonstances que nous avons traversees; et par ailleurs le poste dans l’enseignement que j’ai pris en Octobre est venu beaucoup m’occuper. J’ai ´ e´ nomme´ professeur de Mathematiques ´ ´ ´ de Montpelet Speciales au Lycee ´ ` chargee. ´ lier et j’ai eu jusqu’a` present ces derniers temps une classe tres ´ eves ` Mon travail est beaucoup diminue´ maintenant, beaucoup de mes el ´ e´ mobilises ´ ou allant l’etre, ˆ ˆ me remetayant et de sorte que je pense bientot ´ e´ impossible ces derniers temps, – tre a` travailler pour moi, ce qui m’aurait et a` supposer que j’en aie eu le gout. ˆ ´ e´ tres ` eprouv ´ ´ en cette Vous avez duˆ savoir que l’Ecole Normale a et ee guerre et vous avez duˆ apprendre en particulier la mort si attristante de mon camarade Gateaux. C’est une grande perte. ´ e´ retarde´ jusqu’au Mon mariage qui devait avoir lieu en Septembre a et ´ que l’on ne voulait pas de moi comme moment ou` j’ai su, de fac¸on definitive,
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soldat et il vient d’avoir lieu. Je suis installe´ maintenant avec ma femme a` Montpellier. ´ Montpellier est une ville fort agreable. La vie universitaire y est assez intense. On y jouit d’autre part d’un soleil qui rappelle celui d’Italie que j’ai ´ toujours regrette. ` ´ e´ retardee ´ par la guerre et je viens seulement de Ma these aussi a et recevoir le permis d’impression. Je cherche un imprimeur, mais les journaux ´ mathematiques franc¸ais n’impriment plus et il ne me reste que Gauthier` reconnaissant de me dire si je pouVillars, qui est cher. Je vous serais tres ˆ ˆ vais etre imprime´ (assez vite et sans risquer d’etre laisse´ en plan si l’Italie ´ venait a` intervenir dans le conflit) par un periodique Italien : les Annali ou les Lincei par exemple. Mon manuscrit aura un peu moins de 100 pages ´ ´ imprimees. Je vais ecrire a` Monsieur Dini qui est, je crois, Directeur des ´ Annali ; mais si vous pouviez lui ecrire aussi, je vous en aurai une grande gratitude. ` que vous etes, ˆ ´ J’espere ainsi que toute votre famille en bonne sante. ´ Presentez, s’il vous plaˆıt, mes hommages a` Madame Volterra et mes souvenirs a` tous les professeurs de l’Universite´ de Rome que j’ai connus. Croyez moi, Monsieur et cher Professeur, votre bien respectueusement ´ ´ devou e. ´ es ` J. Per 3, rue Chamayou Montpellier
Document ♣ 2 P´er`es to Volterra . Montpellier, 8 January 1916 Cher Monsieur, ´ Voici bien longtemps que j’ai l’intention de vous ecrire et je vous prie de ´ e. ´ J’ai croire que si je ne l’ai pas encore fait ce n’est point faute de l’avoir desir eu beaucoup a` faire pour ma classe le trimestre dernier car il y aura cette ´ des concours d’entree ´ a` l’Ecole Normale et a` l’Ecole Polytechnique annee et j’ai un assez grand nombre de candidats a` ces Ecoles. La naissance ´ il y a juste trois mois - est venue me donner un surcroˆıt d’un fils – arrivee ´ d’occupations agreables sans doutes mais non moins attachantes. Main´ tenant l’enfant commence a` grandir, ma femme est tout a` fait retablie et j’ai de nouveau quelques loisirs. ` pu travailler pour moi ces Tout ceci vous expliquera que je n’ai guere ` temps-ci. J’ai publie´ les vacances dernieres deux petites notes; l’une que je vous envoie, l’autre dans les comptes rendus, dont je n’ai pas d’extraits, ´ eralisation ´ sur une gen des fonctions de Bessel que je voudrais continuer ´ d’etudier.
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160
J’ai eu, le trimestre dernier, l’occasion d’analyser, pour le bulletin des ´ Sciences Mathematiques vos belles lec¸ons sur les fonctions permutables faites a` l’Universite´ de Princeton en 1912 et j’ai eu beaucoup de plaisir a` ˆ pour le Bulletin des leur lecture. Je pense que cette Analyse paraˆıtra bientot ´ Sciences Mathematiques. ´ vos travaux sur l’Electricite´ Je n’ai pas rec¸u, et je l’ai beaucoup regrette, ´ dans les Rendiconti, dont vous m’annonciez l’envoi dans votre publies ` lettre. Le paquet a duˆ se perdre; le service des postes ne peut derniere ´ ´ ` evidemment se faire aussi reguli erement qu’en temps de paix. Permettez moi, cher Monsieur, de vous adresser a` l’occasion de la nou´ tosu mes vœux de bonheur et de bonne sante´ pour vous et velle annee ˆ ` des armees ´ italipour les votres. Je forme aussi des vœux pour le succes ´ a` distinguees ´ si brillamment dans cette dure guerre de ennes qui se sont dej ˆ montagne et qui continuent a` progresser, meme en plein hiver. ´ verra-t-elle la fin de la guerre? Cela semble peu probable; Cette annee ˆ ˆ mais on sent tout de meme que nos adversaires commencent a` etre las alors que coordinant mieux leurs efforts et corrigeant les fautes commises ´ vont pouvoir donner leur effort maximum. On espere ` tout de meme ˆ les allies ´ acle ˆ que la deb allemande sera brusque – auquel cas nous pourrions peutˆ ˆ ` que nous ne le croyons. etre en etre plus pres ´ Veuillez agreer, Cher Monsieur, l’expression de ma bien respectueuse ´ mes hommages a` Madame Volterra. admiration et veuillez presenter ´ ´ Croyez moi, cher Monsieur, votre bien affectueusement devou e. ´ es ` J. Per Adresse: Pavillon de l’Horloge Enclos Laffoux Montpellier (Je n’habite plus rue Chamayou depuis Aout ˆ dernier)
Document ♣ 3 P´er`es to Volterra . Montpellier, 7 September 1916 Cher Monsieur, ´ e´ nements militaires pleins Depuis que j’ai rec¸u votre lettre des ev ´ d’importance ont eu lieu qui semblent permettre d’esperer, pour le courant ´ 1917, la fin de la guerre. Nous avons tous ici et ´ e´ pleins d’admiration de l’annee pour la brillante fac¸on dont les troupes italiennes, qui venaient de supporter ` frappant maintenant un rude choc, ont enleve´ Gorizia. ll est vraiment tres ` encourde voir avec quelle pre´ cision on a obtenu l’unite´ du front; il est tres ´ et il faut ageant de constater que sur tous les fronts l’initiative est aux allies ´ en guerre de la Roumanie, et peut-etre ˆ espe´ rer que l’entree aussi de la ` va raccourcir encore cette guerre. Grece
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Je ne vous ai pas encore envoye´ mon travail sur les fonctions de Bessel. C’est que je suis amene´ a` son propos, a` travailler dans les voies que vous avez ouvertes dans votre dernier me´ moire des Lincei (Teoria delle potenze. . . ecc. . .) et j’attends d’avoir un tout complet pour vous l’envoyer. ´ Dans ce travail, j’aurai en particulier a` indiquer les resultats suivants: dans ´ ´ votre Memoire, vous avez defini formellement les fonctions d’ordre quel´ ´ conque negatif. On peut aussi les definir effectivement comme des fonctions ´ erement ` ordinaires a` condition de modifier leg de fac¸on correspondante a` la ´ ´ definition de la composition: il suffit d’y remplacer l’integrale
y x
´ ´ par la partie finie (selon la definition de M. Hadamard) de cette integrale. Vous vous rendez compte que dans cette direction il y a pas mal de choses ´ a` faire et je n’ai pas encore tout a` fait termine´ les developpements que je ´ veux donner a` cette idee. ˆ Ensuite j’avais l’intention, si toutefois vous-meme n’avez pas l’intention ´ de developper cette question, et si vous me le permettez, de chercher a` ´ ´ developper cette theorie des fonctions de composition dont vous avez jete´ ´ les bases dans votre dernier memoire. Je lirai avec beaucoup de plaisir vos nouveaux travaux sur la propagation ´ des courants. Ce sont des travaux qui feront epoque dans l’histoire de la ´ Physique Mathematique. ` que vous passez d’agreables ´ J’espere vacances. Je suis maintenant a` ` un mois passe´ dans les Pyren ´ ees ´ Caen, chez mes parents, apres a` me ` completement, ` reposer a` peu pres ce dont d’ailleurs j’avais besoin. Je resterai ici, ou` mon adresse est ` Caen (Calvados) 50, rue Ecuyere jusqu’a` fin septembre, pour rentrer alors a` Montpellier. ´ Veuillez presenter, je vous prie, mes hommages a` Madame Volterra, et ´ accepter l’expression de mon bien respectueux devouement. ´ es ` J. Per Mes parents me prient de les rappeler a` votre bon souvenir.
Document ♣ 4 P´er`es to Volterra . Montpellier, 20 January 1917 Cher Monsieur, ´ pour vous exprimer encore toute mon Je profite de la nouvelle annee affection et pour vous adresser les vœux de bonheur et de bonne sante´ que
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´ je forme, pour vous et votre famille. Il faut esperer que 1917 nous apporte la ˆ paix, mais non celle que nous ont offerte les Allemands, mais bien la notre. ´ J’ai rec¸u et corrige´ les epreuves de ma Note que je vous remercie d’avoir ´ ´ a` l’Academie ´ present ee dei Lincei. J’ai quelques remords de vous avoir ˆ ´ e´ –, inflige´ une lecture assez indigeste car pour etre bref - et je ne l’ai pas et ´ j’ai duˆ condenser la redaction et supprimer toute application. Il y en a pourtant pas mal. Voici par exemple une remarque, a` laquelle j’ai duˆ me contenter de faire une allusion en note. ´ ` J’arrive au 4 a` former une fonction parfaitement definie dont les regles de ˆ ´ composition sont de meme parfaitement definies (aux II et III de ma Note) et telle que ∗ −1 ∗
∗ ∗ −1
f=f f
f
∗0
=I
´ ´ n’ayant pas un sens symbolique, mais exprimant que la suite les egalit es ∗ −1
∗ ∗ −1
∗
∗0
´ des calculs a` effectuer pour calculer f , f et f f donne pour resultat I . ˆ a` cette fonction la solution d’une equation ´ Grace
(1)
∗∗
∗
∗
∗ −1 ∗
∗
∗
∗ ∗ −1
f ϕ =ψ est ϕ = f
ψ
´ et la solution d’une equation (2)
∗ ∗
ϕ f =ψ est ϕ =ψ f
∗ −1
´ ´ ´ Consequence. Si on a resolu (1) on connaˆıt f et on peut ecrire, sans nouveau calcul et a priori la solution de (2). ´ ´ Je mets ainsi en evidence une relation entre les equations (1) et (2) ´ par la methode ´ ´ masquee ordinaire de resolution. Voici un cas particulier: ´ Quand vous determinez (Fonctions de lignes, p. 162, 163) les fonctions permutables avec une fonction F du 1er ordre mise sous forme canonique, ´ ´ vous avez a` resoudre les equations ∗ ∗
∗
∗ ∗
∗
ΦF =Ψ
F Φ=Ψ ` De la 1ere, vous tirez
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Φ=
∂Ψ + ∂y
y
Ψ(x, ξ )g12 (ξ, y)dξ.
x
C’est a` dire ∗ −1
∗
Φ =Ψ (1 ∗ −1
∗
+ g12 )
∗
La fonction F −1 est donc 1 + g12 . ` les regles ` ` D’apres de calcul de ma Note, la solution de la deuxieme ∗ ∗
∗
´ equation (F Φ=Ψ) sera (sans qu’on ait, pour la trouver, a` faire de nouveaux calculs) ∗
∗ −1
Φ= (1
∗
∗
+ g12 ) Ψ
ou ∂Ψ Φ=− + ∂x
y
g12 (x, ξ )Ψ(ξ, y)dξ.
x
´ En consequence, les deux fonctions que vous nommez g12 et g21 sont ´ ´ et ˆ de curiosite. ´ identiques. C’est facile a` verifier. Cela n’a qu’un inter ´ J’ai envoye´ a` l’Academie des Sciences de Paris un pli cachete´ contenant ´ ´ ´ les principaux des resultats – Sur les developpements en serie de fonctions ` lettre.368 Je puis ainsi permutables – dont je vous ai parle´ sans ma derniere ´ travailler encore quelque temps sur ce sujet, qui m’interesse. Excusez moi de vous avoir entretenu si longuement de moi.
368
The procedure of Pli cachet´e (sealed letter) is proposed by Paris Academy to allow a scientist to prove his priority on a discovery. The letter is not opened till the scientist himself does not ask for it, or a period of 100 years has passed. In some exceptional cases, the opening may also be asked by members of the scientist’s family. The latter happened for instance in 2000 with the opening of Doeblin’s last memoir on Kolmogorov’s equation required by Doeblin’s brother (see details in [10]). Generally, the pli cachet´e is used when the scientist is worried about his personal destiny (in case of war for instance) or in case of hard competition. As he could not have been worried for his own security, P´er`es had probably feared possible competitors but it is not clear who they could have been, apart from Volterra himself. Maybe he had in mind the young American mathematicians, in particular Evans who was in Rome just before himself and was in very friendly terms with Volterra. Evans is quoted together with P´er`es in the introduction of the aforementioned Volterra’s 1916 memoir at the Lincei as the two persons having systematically developed Volterra’s researches on integral equations. Moreover, in January 1917, the USA have not yet entered the war and P´er`es was maybe anxious to consolidate his position. The pli cachet´e was officially registered by Paris Academy on 29 January 1917 under the title Sur certains d´eveloppements en s´eries. P´er`es asked the opening of his letter on 8 April 1918. The contents was given for reviewing to Hadamard, and subsequently published in the Comptes Rendus de l’Acad´emie on 6 May 1918.
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` ˆ J’espere que cette lettre vous trouvera, ainsi que tous les votres en ´ Presentez, ´ bonne sante. je vous prie, mes hommages a` Madame Volterra ´ mes sentiments de bien respectueux devouement. ´ et veuillez agreer ´ es ` J.Per Enclos Laffoux Montpellier
Chapter ♥ 8
Persuading the American Jewish Community
As seen from a letter sent by Hadamard to Volterra on 3 April 1916, there was then an urgent need of propaganda directed towards the American Jews to convince them to relinquish their pro-German feelings. The reaction of the Jewish communities in World War 1 is a not so widely known question, though it has been studied by several authors. See in particular the important essay [55]. In this brief section, it is not our intention to give a full picture of this complicated matter, but only to explain how Hadamard and Volterra had got involved into this question. Before quoting many letters related to this involvement, we use several secondary sources to draw a picture of the situation related to the Jewish communities since 1914. As Hadamard clearly explicits in his letters, the corner stone of the problem is to be found in the visceral hostility to the czarist regime from the Jews who fled from Russia because of anti-semitic persecutions during the two decades preceding the war. Many of them had settled down in France and they found themselves in an ackward and uncomfortable situation when the war was declared. This situation was studied in detail by [33], pp. 43–56. Many of the members of the Russian Jewish community in France felt as much love for their new country as hatred for the old one - and France and Russia were allies. As strangers coming from a country of the Entente, they had the choice either to return to Russia to join the Russian army, which was out of question for almost all of them, or to enlist in France. Many of them wished to join the French Army, and a great number did. However, instead of placing them with regular troops, the French military administration incorporated them in the L´egion e´ trang`ere which carried the bad reputation of being a place for thieves and murderers. This fact quickly cooled down the patriotic spirit and the enlistments dried up. Moreover, when the hope of a quick conclusion to the war vanished, the French population became less benevolent to the foreigners, especially for these Germanic language speaking refugees who had abandoned an allied country. Several strict police repressive measures where decided – in particular frequent controls of their identities and of their permits given to stay in France. The situation worsened when the Russian armies began to be severely defeated on the Eastern front by the Germans and the Austro-Hungarians. Precise figures do
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not exist for the horrors unleashed by the Russian army as it retreated in the first part of 1915, perpetrating wholesale massacres and civilian expulsions, but estimates of the number of refugees by the end of 1915 range to several million. Jews were among the hardest-hit by this whirlwind. In Russia’s western borderlands the army took advantage of the carte blanche it had received from the tsar to implement a wide range of anti-Jewish measures. These included large-scale expulsions (20,000 from Polish cities during late January 1915, for example), random violence and looting, and widespread hostage-taking on the grounds that Jews were surely sympathetic to the Central Powers, if not actively engaged in anti-Russian espionage. Persecutions of Jews intensified in the early months of 1915, with mass expulsions from Polish territory, from Galicia, and from the north-western provinces of Kovno and Courland. Expulsions were generally carried out at extremely short notice, often between twenty-four and forty-eight hours. The American Jewish Committee’s report on the situation of the Jews in the war zone conservatively estimated that in June 1915 at least 600,000 Jews were “homeless” and “ruined” in the Polish lands and the north-western districts of Russia. Brutality was a hallmark of the Russian treatment of the Jews (see [48], pp. 67–69). Chapter 12 of [54] gives moreover an interesting insight of the domestic situation of the Russian Jews. If, at the beginning of the war, the Jewish press in France followed the sacred union, the terrible situation on the Eastern front led it to allude more and more openly to the situation of the Russian Jewry and to face problems with censorship. In 1916, the sacred union dissolved and the Zionists did not accept any more the cautiousness of the Jewish notability. They began to openly ask France to condemn the czarist regime and to break up with his ancient ally. See [32], pp. 131–133. All this was not susceptible to increase the confidence of the Jewish community towards the Allies. Nor was it of a nature able to convince the American Jewry of acting in the support of American intervention. In fact, on the contrary, many were thinking that Germany had a more tolerant policy and was more inclined to offer political and religious freedoms to its minorities than the detested Russia. Several studies exist about the complicated question of the attitude of American Jews to the war in Europe and the possibility of an American participation. Let us quote in particular the important study [55] where the Russian question in USA is treated in details. In France, several personalities worried about the situation and became convinced of the necessity of reversing the attitude of the influent Jewish community in America. A French Information and Action Committee Among Jews in Neutral Countries was created in December 1915 and among its leaders were both Jews and non-Jews. The President was Georges Leygues, head of the Commission for Foreign Affairs at the Parliament. It has been evoked that the Committee may have been organized at the request of the French Ambassador in the United States. On these subjects, see [55], pp. 49ff. With the other Jewish association, the Alliance Isra´elite Universelle, the Committee decided to send the professors Nahum Slousch and Victor Basch to the USA in order to secure the American support of the French cause. During the spring 1916, Basch informs the Alliance of the American skepticism, which he interprets
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as a pro-German attitude. Though he tried to change the situation by giving several speeches on a favorable evolution in Russia thanks to the war, the mission was a failure and Basch pointed out that the Russian policy towards Jews was entirely responsible for the fact. If Russia showed some good will towards improving this situation, certainly “the whole American Jewry would march on the Allies’ side”. In February 1916, an Association for the Russian Victims of the War was created where several intellectuals of great fame were very active, in particular Sylvain L´evi (1863–1935). The latter was a philologist specialist in the languages in India; for details on his important works, see[5]. It was as a specialist in India that he met Filippo de Filippi, a geographer from Rome who participated in scientific expeditions to that country. L´evi contacted the baron Rotschild to obtain support from the Papacy and Warsaw Archbishop to limit pogroms and deportations. Reference [32] (p. 155) explains how Rotschild felt reluctant to the idea, fearing that such an intervention could be understood as a pro-German statement or at least as a dent in the sacred union. The Dreyfus Affair was still very fresh in the memory of this generation. As we have seen, Hadamard asked Volterra whether a similar kind of action was possible in Italy. He transmitted a letter by Sylvain L´evi to him (DOCUMENT ♣ 5). The interested reader can find some details about Volterra’s attitude to his Jewish origin in [23] (see in particular the introduction).
Document ♣ 5 Sylvain L´evi to Volterra . Paris, 12 April 1916 ` Monsieur et cher collegue, ` J’ai l’honneur de m’adresser a` vous, sous les auspices de mon collegue et ami M. Hadamard chez qui j’avais eu la bonne fortune de vous rencontrer. Il faut, d’autre part, que je vous avoue que, si je prends la liberte´ de recourir a` vous pour l’œuvre dont j’ai a` vous entretenir, c’est sur la bienveillante et ` sage indication de M. le Dr De Filippi, votre collegue a` l’Universite´ de Rome. ´ J’ai eu l’occasion de le voir recemment a` Paris, au retour d’une mission a` ´ pour la tache ˆ Londres; je l’ai consulte´ sur la personnalite´ la plus qualifiee a` ˆ design ´ ´ entreprendre, et il vous a aussitot e´ sans un instant d’hesitation. ´ ets ˆ qu’elle met en jeu et par les quesLa guerre actuelle, par les inter ` ´ ´ tions qu’elle souleve, s’etend a` l’univers entier. Les pays belligerants ne ´ se bornent pas a` recruter des alliances; ils ont a` se preoccuper aussi des ´ officiellement neutres qui peuvent leur procurer les ressources pays restes ´ necessaires a` la lutte. Dans le groupe des Etats neutres, les Etats-Unis ´ ´ tiennent une place prepond erante; dans les Etats-Unis, la population juive ´ exerce une influence incontestable: dans l’etat de New-York, qui donne le ´ ton a` la Republique, les Juifs comptent comme un des facteurs politiques les plus puissants a` la fois par leur nombre et par leur situation. Ces Juifs
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sont les uns d’origine allemande ; les autres d’origine russe; les uns, par attachement a` leur ancienne patrie, les autres, par rancune contre un pays ´ le conqui les a contraints a` s’exiler, refusent d’apporter a` la cause des allies ´ cours de leur influence et de leurs capitaux. Trop recemment introduits dans ´ ˆ ´ a` l’esprit et les traditions, ils la nation americaine pour s’en etre assimile´ dej ´ et ˆ sur la question juive qu’ils ont eu l’occasion de concentrent tout leur inter ´ connaˆıtre, il est vrai, par des experiences cruelles. Pour justifier leur attitude, ´ ils accusent les Juifs de l’Europe Occidentale de froideur et d’indifference; ils leur reprochent d’assister impassibles au martyre des Juifs de Russie et de Pologne. ´ ´ ´ Notre devoir est de reagir contre ces preventions, habilement exploitees ´ et ˆ de par des ennemis sans scupules. Notre devoir commun, dans l’inter ´ l’Alliance, c’est de prouver aux Juifs d’Amerique que, Juifs d’origine, sinon de foi ou de conviction, nous savons les obligations de solidarite´ que notre naissance nous impose et que le sentiment d’humanite´ suffirait a` nous prescrire. avec l’approbation et les encouragements de notre Gouvernement, ` des Juifs nous avons constitue´ un Comite´ d’Information et d’Action aupres des Pays neutres; les documents que je joins a` ma lettre vous en feront ˆ Nous nous attachons essentiellesaisir nettement la conception et le role. ` le ment aux manifestations qui, dans l’ordre juif, mettent en pleine lumiere ´ liberalisme traditionnel de la France des Droits de l’Homme. Samedi dernier ´ les plus autorisees ´ encore, nous avons convoque´ les personnalites de la ´ erale ´ ´ ees ´ colonie juive de Paris, que les mesures de police gen mal interpret ´ et nous avons pu leur donner officiellement l’assurance ´ ee, avaient inquiet ` aux usages de l’hospitalite´ et au droit que la France en guerre restait fidele ´ d’asile. Pour repondre a` des vœux formels qui nous venaient de l’autre ˆ e´ de l’Atlantique, nous avons forme´ une Commission chargee ´ d’etudier ´ cot ´ avec les methodes de la science la plus rigoureuse, les questions qui ont ´ trait aux Juifs Russes et les solutions proposees. Cette commission doit ´elaborer un memoire ´ ´ qui servira, nous avons tout lieu de l’esperer, aux ´ ` ´ plenipotentiaires franc¸ais lors du Congres qui definira l’Europe Nouvelle. ´ de M. le baron Edmond de Rotschild, Cette Commission est composee ´ ¨ Levi; ´ ´ ancien prefet, ´ president; M. le Grand-Rabbin Israel M.E.See, vice´ ´ ´ ´ president de l’Alliance Israelite; M. le Dr Netter, de l’Academie de Medecine; M. Salomon Reinach, de l’Institut; M.Albert Wahl, de la Faculte´ de Droit; M.Durkheim et M.Basch, de la Sorbonne, et de moi. Le juda¨ısme anglais ´ une organisation similaire; le Conjoint Committee qui a bien coulu creer ´ represente l’ensemble des organisations juives de l’Angleterre, sous la ´ presidence de M. de Rothschild, s’est abouche´ avec le Foreign Office et ´ travaille d’accord avec lui; il a envoye´ son secretaire, M. Lucien Wolf, a` Paris ´ les deux organisations, tout en pour prendre contact avec notre Comite, restant absolument autonomes, travaillent a` l’œuvre commune en servant ´ elle aussi, un organe du ´ et ˆ national. Il est a` souhaiter que l’Italie cree, l’inter ˆ meme genre, dans des conditions analogues. Le jour ou` les trois nations qui ´ representent tant en Europe l’esprit de liberte´ auront garanti par une triple
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´ et ˆ qu’elles entendent porter a` ces questions juives qu’il manifestation l’inter ´ ´ n’est plus permis d’eluder ou d’ignorer, le juda¨ısme americain rassure´ ne manquera pas de s’ouvrir a` nous pour seconder nos efforts. Il va sans dire que si cette œuvre deait compromettre l’unite´ de l’Alliance, nous n’y aurions pas songe´ un instant; d’ailleurs ni le gouvernement anglais, ni le gouvernement franc¸ais n’auraient encourage´ une œuvre susceptible de leur nuire. ´ La question juive existe officiellement en Russie; le gouvernement imperial ´ ` a charge´ plus d’une commission de l’etudier; elle fait partie du probleme ´ qui complique si lourdement l’appareil de l’Empire russe. des nationalites L’occupation de la Pologne par les Allemands, en supprimant le “Territoire” a supprime´ la solution du “statu quo”; il faut trouver une solution nouvelle, ` ´ et cette solution, se reliant d’une part au probleme de l’emigration, d’autre ` ´ ´ ´ part au probleme du developpement economique international, depasse la ´ d’une question d’ordre interieur ´ ´ portee et interesse le monde entier. ´ a` que, si je me suis permis cette demarche ´ J’aurais duˆ vous expliquer dej ` de vous, ce n’est pas a` titre personnel, fut-ce ˆ aupres meme avec la comˆ ´ plicite´ de mon ami Hadamard; j’en aurais senti trop vivement l’indiscretion ´ pour m’y laisser entraˆıner. C’est comme vice-president de notre Comite´ que j’ai rec¸u le mandat de m’adresser a` vous pour vous solliciter, de la part de ´ de prendre l’initiative d’organiser un comite´ italien analogue notre Comite, ´ de France et d’Angleterre en vue d’exercer une action sur les aux Comites Juifs des pays neutres. J’ai accepte´ comme un grand honneur ce mandat ´ qui me met en rapport avec un savant universellement connu et respecte. ´ ` Veuillez agreer, Monsieur et cher collegue, l’expression de mes senti´ ments les plus distingues. ´ Sylvain Levi.
Chapter ♥ 9
French Propaganda
A central figure of French propaganda in Italy during the war was the historian Julien Luchaire (1876–1962). He was a professor of Italian literature at the University of Grenoble and a prominent specialist of the Italian Renaissance. He wrote his memoirs, Confessions d’un franc¸ais moyen [37]. The book gives an exceptional insight of this period in Italy, in the eyes of a French scholar in contact with the whole Italian intelligentsia. In 1907, Luchaire founded the French Institute of Florence and soon became one of the most influential French actors in Italy. When war broke out in 1914, the French Government asked him to become an agent of the Comit´e Parlementaire en Italie, which is to say an agent of propaganda for Italian intervention in the war. Another French agent in Italy was Henri Gonse, a friend of the ambassador Camille Barr`ere. Gonse became the director of the Maison de Presse founded in 1916, an institution devoted to the extensive examination of Italian press during the war. The fact that the French government was interested in the Italian press is also testified by some obscure financing of Italian newspapers. On the subject, see J.P. Viallet: Aspects de la propagande franc¸ise en Italie pendant la premi`ere guerre mondiale, in [25] pp. 200–245. Luchaire struggled especially against pacifism and against Germanophiles, who were present among Italian intellectuals at least in the years 1914–1915 – the philosopher Benedetto Croce (1866–1952) was one of them (see in particular the long and interesting description of the months preceding this intervention (pp. 25–40) in Luchaire’s Memoirs). A fervent catholic, Luchaire had contacts with many Italian and French Catholic politicians and intellectuals. At the beginning of the war, Italian Catholics were generally neutralists and among the French Catholics emerged a movement aimed at convincing their Italian “brothers” of the necessity of the war against the Central empires. Luchaire belonged to this movement and was seconded by a group of French catholic scholars. The historian Maurice Vaussard (1888–1978) was asked to head the French Institute of Milan, which was strongly involved in political propaganda. Another catholic, Henri B´edarida (1887–1957), later professor of Italian literature at the Sorbonne, was attached to the French Institute of Florence as a translator. Among Luchaire’s collaborators were also the
L. Mazliak, R. Tazzioli, Mathematicians at war, Archimedes 22, C Springer Science+Business Media B.V. 2009 DOI 10.1007/978-90-481-2740-5 9,
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historians Jean Alazard (1887–1960) and Augustin Renaudet (1880–1958).369 After the Italian intervention, Catholics gradually accepted the war, and in 1916 a Catholic, Filippo Meda (1869–1939), became minister of Finance in Boselli’s government. Meda was the founder of Civitas, one of the most important Catholic journals of the 20th century. The Roman Church officially disapproved of Meda’s attitude towards politics, though more and more Catholics were willing to play a political role in Italy. On 20 May 1916 in Paris, Gaston Maspero (1846–1916) founded a new committee, the Comit´e du Livre as a new tool for French propaganda in foreign countries. He was a famous Egyptologist; in 1869 he became a teacher of Egyptian language and ´ ´ archeology at the Ecole Pratique des Hautes Etudes and in 1874 he was appointed to the chair of Champollion at the Coll`ege de France. He succeeded Auguste Mariette as Director of the Egyptian Museum, and edited the first fifty volumes of the catalogue of the collection there. From 1880 onwards, he was also at the head of many French archeological missions for excavations in Egypt. But he soon died and was replaced by the paleographer Jacques de Dampierre (1874–1947). The Comit´e du Livre aimed at developing French culture by the promotion of French books and various cultural institution as it is clearly expressed in the first Statute approved by the general Assembly (18 April 1916).370 As Dampierre wrote in his Report – presented at the general Assembly on 5 May 1917371 – the activity of the Comit´e had four objectives: i. ii. iii. iv.
Bibliography, with the aim of exporting French culture abroad; Improvement of French books by creating a better organization; Propaganda of French ideas abroad and, reciprocally, of foreign ideas in France; Foundation of a Museum of the Book in Paris, which represents a kind of Pantheon of French culture.
The idea of founding the Comit´e du Livre was due to Volterra, as it is clearly expressed by his friend, the French consul in Rome Tondeur-Scheffler (DOCUMENTS ♣ 6–♣ 8) reported below. Tondeur-Scheffler was a member of the Committee since its foundation (he was subsequently appointed vice-president in 1918). Volterra’s idea was part of a wider project which concerned the creation of stronger cultural and institutional relations between Italy and France. His efforts also led him to found the Associazione italiana per l’intesa intellettuale tra i Paesi alleati e amici, instituted in Rome in 1916 (see also ♥ 10 ). This Association aimed at promoting Italian culture abroad by improving relations between Italian cultural institutes and similar institutes in the allied countries. It encouraged the teaching of Italian language abroad, exchanges of professors and students, and any kind of
369
On Italian and French Catholics during the war see J. Gadille, L’alliance intellectuelle entre catholiques franc¸ais et italiens pendant la premi`ere guerre mondiale, in [25], pp. 139–157.
370
Fond Dampierre, 289AP.33, Archives Nationales, Paris.
371
Fond Dampierre, 289AP.33, Archives Nationales, Paris.
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intellectual enterprizes and organizations. These purposes are clearly explained in the first issue (1918) of L’intesa intellettuale, the journal of the Association which was directed by Andrea Galante (1871–1919), a professor of canon law at the University of Bologna.372 This journal, which also contained papers in French, payed much attention to the teaching of Italian language abroad – at secondary schools and universities – and, generally, to the organization of education in Italy and in the allied countries. The Associazione italiana per l’intesa intellettuale tra i Paesi alleati e amici represented the Italian twin of the Comit´e du Livre, as TondeurScheffler wrote to Volterra. However, it would be a mistake to believe that after, the beginning of the Italian intervention, the French propaganda in Italy was limited to cultural aspects. After Caporetto, there were a number of pacifist demonstrations in Italy and the number of desertions in the army increased. As it is claimed in a French military report,373 the “defeatist” newspaper L’Avanti (a socialist newspaper which later became Mussolini’s official organ), which had a great influence and was widely read by soldiers, supported the pacifist propaganda. In addition, an insurrectional movement was expected for 24 May 1917, the third anniversary of the diplomatic rupture between Italy and Austria. Luchaire took part in the campaign against the pacifist organizations. In 1918, he asked his government to send some severely wounded French soldiers to Florence, so that they could convince the audience of the necessity of continuing the war by telling them their personal stories (DOCUMENTS ♣ 9–♣ 10). Luchaire wrote several times to Paris urging the authorities to send French wounded soldiers to Italy, and he eventually succeeded . An article in the Corriere della Sera dated from 14 June 1918 (DOCUMENT ♣ 11) alludes to the fact.
Document ♣ 6 Tondeur-Scheffler374 to Volterra . Rome, 25 September 1915 ´ Monsieur le Senateur, ` En m’excusant de vous importuner, je me permets de vous prier, des ´ que vous la possederez, de vouloir bien me communiquer la liste du Comite´ Italien pour que nous poussions a` la constitution de celui de Paris. ´ ´ e´ bien Je saisis cette occasion pour vous ecrire combien vous avez et ´ hors de votre derniere ` reunion, ´ inspire, de conseiller le secret absolu sur 372
These and others notices on the Associazione italiana per l’intesa intellettuale tra i Paesi alleati e amici can be found in the paper F. Picco: L’insegnamento della lingua francese in Italia e della lingua italiana nelle scuole di Francia, Nuova Antologia, s. 6, vol. 194, 1918, pp. 373–384.
373
Archives of the Service Historique de l’Arm´ee de Terre (SHAT) in Paris. Dossier 17 N 525 dated 26 March 1918; the word SECRET is put in evidence. 374
The letters by A. Tondeur-Scheffler to Volterra are contained in the Volterra’s Archive, Accademia dei Lincei, Rome
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´ nos efforts actuels. C’est plus que jamais necessaire, j’en ai chaque jour la preuve – n’estimez vous pas a` ce sujet, qu’il serait bon que nous nous ´ consultons reciproquement avant de parler a` qui que ce soit, de nos projets? J’ai, en effet, observe´ que, souvent, on me parlait de ceux-ci dont on avait vaguement entendu parler dans le seul but de se renseigner plus exactement afin soit d’en tirer parti personnel, soit d’y faire obstacle: il y a la` pour ´ ´ ´ la periode de debut, surtout, un danger qu’on ne saurait trop eviter. ´ Monsieur le Senateur ´ ´ Veuillez agreer les assurances renouvellees de ´ ´ mes sentiments de haute consideration et d’entier devouement Tondeur-Scheffler
Document ♣ 7 Tondeur-Scheffler to Volterra . Rome, 8 October 1921
` S.M. le Roi d’Italie Ambassade de la Republique Franc¸aise pres ´ Monsieur le Senateur, Cette lettre vous sera remise par M. Albert Willm, Avocat a` la Cour ´ d’Appel de Paris, Adherant au Comite´ du Livre et qui sera d’ici peu, sans doute, son Avocat Conseil.375 ´ que je viens d’enumerer, ´ A l’occasion d’un voyage en Italie et des qualites ` du President ´ M. Albert Willm a bien voulu accepter de se charger pres du Comite´ Intesa Intellettuale (soeur jumelle du Comite´ du Livre, ne l’oubliez pas) de la mission de renouer entre Paris et Rome des liens qui, non seule´ ´ ment sont veritablement pas trop detendus, mais qu’encore, et a` tout prix, ˆ e´ et d’autre a` rendre reguliers. ´ nous devons nous efforcer de cot ´ Je n’ai pas a` vous rappeler, en effet, les si interessantes conversations que nous avions a` votre domicile hospitalier avec vous et Monsieur le ´ e´ des plans Marquis de Viti di Marco376 : a` ce moment nous avons elabor ´ interessants.
375
Albert Willm (1867–?) was a lawyer and a politician of the Socialist Party and a Member of Parliament.
376
The right name is Antonio de Viti de Marco (1858–1943); he graduated in law from the University of Rome in 1881 and in 1887 was appointed professor of financial sciences at the University of Rome. He had liberal ideas and considered economics as the crucial point of the political debate. He was against Fascism and in 1931 he refused to take an oath of loyalty to Fascism, as Volterra did. As a consequence of his refusal, he was expelled from the University of Rome.
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Depuis mon retour a` Paris, je me suis formellement promis d’en pour´ suivre l’execution. ´ M. Willm vous indiquera quels sont, a` ce sujet, les desirs du Comite´ du Livre. ´ ´ Je me permets d’y ajouter la suggestion que j’ai maintes fois preconis ee ´ ´ ceux des proces-verbaux ` d’echanger entre nos deux Comites, de nos ´ ´ ´ reunions pouvant nous interesser reciproquement et, d’autre part, de nous ˆ ` de nos Gouvernements pour toutes les quespreter un appui mutuel pres ´ tions d’ordre intellectuel qui interessent nos deux pays. ´ ´ ´ Vous hesiterez d’autant moins a` reserver un accueil favorable aux idees ´ que je viens d’avoir l’honneur de vous exposer que je connais, par experience, ` que je me permets de vous rappeler votre haute bienveillance pour la these ´ et que, d’autre part, le Comite´ du Livre n’a cesse´ d’accroˆıtre son autorite. ` du Livre Je me borne, a` ce propos, a` vous signaler que le dernier Congres ´ ´ et la Semaine du Commerce Exterieur se sont mis d’accord sur la creation d’un Comite´ Intercorporatif, assurant la coordination des efforts poursuivis ´ ´ e´ prie, ´ et il a dans l’ordre intellectuel et economique: le Comite´ du Livre a et ´ de presider ´ accepte, ce Comite´ Intercorporatif. Je suis heureux de saisir cette association de me rappeler a` votre sou´ Monsieur le Senateur, ´ ´ venir, et je vous prie d’agreer, l’assurance renouvelee ´ ´ ´ de ma haute consideration et de mon devou ement. Tondeur-Scheffler
Document ♣ 8 From the speech of Tondeur-Scheffler held at the General Assembly of the Comite´ du Livre from 17 April 1916377 (Statement) ´ M. le President, Messieurs, ´ ´ Je ne puis me derober a` l’invitation de M. le President, mais je m’excuse vivement de prendre la parole devant un auditoire aussi illustre dont je sollicite la bienveillante indulgence. ` brievement ` ´ l’origine de l’idee ´ que je suis tres ` heureux Voici tres exposee ´ ` aussi flatteuse et aussi rapide. Elle est nee ´ a` de voir se realiser de maniere ` dont, comme me le disait le Gen ´ eral ´ Rome, sous les auspices de M. Barrere ´ de Castelnau, “la France ne benira jamais aussez le nom”, et qui infati-
377
Document contained in Archives Nationales (Paris). Fond Dampierre, 289AP.33.
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` gablement sur la breche, ne laisse passer aucune occasion de contribuer vigoureusement a` la Victoire franc¸aise sur tous les terrains.378 ´ Desireux d’intensifier les rapports intellectuels entra la France et l’Italie, ` me mit donc en rapport avec un de nos amis de la-bas, ` M. Barrere M. de ´ Viti de Marco, economiste connu, chef du parti radical au Parlement. Ce ´ dernier me fit entrer en relations avec M. le Senateur Vito Volterra, recteur ˆ de l’Universite´ des Sciences a` Rome, et a` nous trois, nous cherchames le moyen d’atteindre les deux buts suivants: 1 activer les relations franco-italiennes, ´ 2 aider les deux pays par appui mutel a` se degager de la formidable ´ emprise allemande. Ce qu’etait cette emprise, je n’ai pas a` vous l’apprendre. ´ ´ Qu’il me suffise le rappeler qu’elle etait parvenue a` etablir dans ce domaine comme dans tant d’autres un quasi monopole: depuis le livre classique jusqu’au guide, jusqu’a` la partition musicale, jusqu’aux instruments de musique (car je rougis de penser qu’a` Rome je n’ai pas vu un seul piano ´ franc¸ais en magasin). Tout etait allemand, exclusivement allemand! ´ Quelle etait la raison de cette faveur? l’inlassable, la sournoise propagande de nos ennemis: elle y utilisait tous ses sujets, depuis le privat´ docent, veritable fourrier de l’influence allemande, depuis le voyager de ´ commerce, espion et proselyte, jusqu’a` la gouvernante a` la domestique, glissant des prospectus dans les tables de ses maˆıtres. Ajoutez l’influence ` ´ financiere, le formidable moyen de pression politique et economique que ´ constitue un etablissement tel que la Banca Commerciale, succursale occulte de la Dresdner Bank, et vous comprendrez combien difficile et long apparaissait le chemin a` parcourir: modifier les habitudes, bouleverser les ten´ dances, detourner a` notre profit le courant; mais avant tout, sauvegarder les ´ ´ nationales d’un peuple si prompt apparences, menager les susceptibilites a` saisir la moindre nuance, a` prendre ombrage de la moindre influence ´ ` ´ qu’a` l’influence allemande, combattue par des esprits etran ere, bref eviter ´ et nombreux, on ne puisse nous accuser d’avoir de plus en plus distingues ´ ` brusquement voulu substituer une autre influence etrang ere. ` ´ ´ ´ nationaux De la est nee notre idee de collaborer au moyen de comites ´etablis a` Rome et a` Paris, (tout d’abord dans les pays amis de la France), ´ entre eux par des del ´ egu ´ es, ´ composes ´ de telle sorte que soudees ´ relies en un solide faisceau, les forces intellectuelles constituent un instrument capable tout a` la fois d’intensifier, de discipliner la production et d’en assurer ´ et amis. Une enquete ˆ preliminaire ´ ´ la diffusion dans les pays allies effectuee ´ en France et en Italie, dans le monde savant, dans celui des editeurs et des ´ libraires, nous a tout de suite apporte´ les plus precieux encouragements. C’est a` ce point, qu’en ce qui concerne les libraires de toute l’Italie, je crois pouvoir dire que pas un seul d’entre eux n’avait, au moment ou` j’ai quitte´
378 Camille Barr`ere (1851–1940) was French ambassador in Rome and intensely worked to tighten the links between Italy and France in the period 1914–1918.
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´ e´ a` promettre a` notre œuvre le concours le plus empresse, ´ Rome, hesit ` aujourd’hui, vous n’apercevrez plus aux vitrines des libraires et que des romains un seul livre allemand, mais des publications italiennes, franc¸aises ou anglaises. ´ par ces preliminaires, ´ Encourages soutenus d’autre part par Mgr. Duchˆ de passer a` l’action et un esne et M. Alb. Besnard,379 nous tentames ´ suivantes, qui Comite´ d’initiative italien fut constitue´ par les personalites ´ sollicite des adhesions dans le monde universitaire et savant: 3 a` 4.000 sont ´ ´ ´ ´ ´ aux 93 escomptees! (Quelle reponse interessante, si cet espoir est realis e, ˆ intellectuels allemands!) Entre temps, si mes fonctions m’empechent de me ´ ´ egu ´ e´ a` Rome, qui directement n’a cesse´ de deplacer, M. Gonse, notre del ˆ ´ ´ ´ venait a` Paris me preter un concours aussi eclair e´ que modeste et devou e, ´ et me rapportait des renseignements qui me permirent le preciser notre ´ erent ` ˆ œuvre et me decid a` y venir moi-meme: j’y suis depuis 3 semaines. ´ e´ fait, le programme que nous nous proposons, les moyens que Ce qui a et ´ nous envisageons, voila` ce que va vous enoncer M. de Dampierre: venu en ` mission officielle aRome pour s’occuper de la diffusion de son remarquable ouvrage, L’ALLEMAGNE ET LE DROIT DES GENS,380 j’eus en causant avec ´ lui l’impression nette que j’avais devant moi exactement l’homme qui m’etait ´ necessaire pour faire aboutir rapiddement et pratiquement l’œuvre que je ´ ` m’efforc¸ais de creer: je n’ai pas eu a` m’en repentir et je suis sur ˆ qu’apres l’avoir entendu, vous estimerez comme moi, le hasard me l’envoyant a` Rome ´ a` ce moment precis, a bien fait les choses.
Document ♣ 9 Luchaire to Gondrecourt . Milan, 12 December 1917 Republique Franc¸aise Universite´ de Grenoble Institut Franc¸ais de Florence 6 Via Silvio Pellico. Milano381 ´ eral, ´ Mon Gen Je vous remercie de l’obligeance que vous avez mise a` insister au sujet ` de M. le Ministre de la Guerre. Quelque soit du Lieutenant Bedarida aupres mon regret de ne plus pouvoir utiliser sa collaboration pour un travail dont 379
Albert Besnard (1849–1934) was a painter. He was director of the Ecole des Beaux-Arts in Paris and then of Villa M´edicis in Rome.
380
J. de Dampierre, L’Allemagne et le droit des gens. D’apr`es les sources allemandes et les archives du gouvernement franc¸ais, Paris, Berger-Levrault, 1915.
381 This document is contained in Archives du Service Historique de l’Arm´ee de Terre, SHAT, 17 N 525.
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´ ´ ´ ´ les bons resultats etaient evidents, je ne puis que me rejouir qu’on l’aˆıt mis a` une place ou` certainement il sera plus utile encore. Vous jugerez comme moi que le moment n’est pas venu, au contraire, ´ d’abandonner les formes de propagande ecrite et orale. Il ressor des ren´ ˆ es ´ que de plus en plus seignements qui me viennent de differents cot ˆ les orateurs portant uniforme militaire ont chance d’etre mieux accueillis ´ ement ´ et plus efficaces que les civils. Or, j’ai rec¸u precis ces jours-ci du ´ de guerre italiens Comite´ pour la propagande de l’Association des mutiles ` d’interesser ´ la priere l’autorite´ franc¸aise a` un projet qui me parait digne ´ ` de la Guerre franc¸ais de consideration. Il s’agirait d’obtenir du Ministere ´ de guerre franc¸ais qui l’envoi en Italie d’un certain nombre de mutiles ´ de propaaccompagneraient leurs camarades italiens dans leurs tournees gande. On formerait ainsi le plus grand nombre possible de couples com´ d’un orateur italien et d’un orateur franc¸ais, ayant mission de parler posees ´ devant les publics civils et militaires des differentes villes. Le programme ´ de ces conferences et leur organisation sont a` la charge de l’Association ´ ´ italienne; d’autre part j’ai ici tout le materiel necessaire pour fournir ces ´ franc¸ais de cliches ´ de projection. Le Ministere ` de la Guerre n’aurait mutiles ´ ´ lesquels d’ailleurs donc qu’a` designer quelques officiers ou soldats mutiles, n’auraient pas besoin de connaˆıtre et de manier aussi bien l’italien que le faisait Bedarida. ` oblige´ de vouloir bien me donner votre opinion a` ce Je vous serai tres ´ eant, ´ ` sujet et me dire si, le cas ech vous seriez dispose´ a` intervenir aupres du Ministre de la Guerre pour cet objet. ´ eral, ´ Veuillez recevoir, mon cher Gen l’assurance de mes sentiments de ´ particulier devouement. J. Luchaire
Document ♣ 10 ´ Communication to Clemenceau 13 February 1918 A/S de la propagande orale en Italie382 ´ Monsieur le President du Conseil, Ministre de la ´ - 2e Bureau I) GUERRE (Etat-Major de l’Armee PARIS
382 This document is contained in Archives du Service Historique de l’Arm´ee de Terre, SHAT, 17 N 525.
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Monsieur LUCHAIRE, Directeur de l’Institut Franc¸ais de Florence, me fait ´ et ˆ que presenterait ´ ´ connaˆıtre l’inter la venue en Italie de quelques mutiles ´ a` la propagande orale aupres ` des de guerre franc¸ais qui seraient employes ` du public civil. troupes et aupres Les conditions que devraient remplir ces militaires seraient les suivantes: ´ ements ´ Etre en possession des el de la langue italienne, ´ Etre capable de parler en public, bien qu’en toute simplicite, Avoir du tact et de la bonne humeur. ˆ ´ a` et ´ e´ l’Officier interprete ˆ BEDARIDA, Ils pourraient etre mis comme l’a dej a` la disposition de l’Institut Franc¸ais de Florence, et devraient recevoir, outre ´ ´ leur solde, une indemnite´ de residence a` l’etranger.
Document ♣ 11 Cutting from Corriere della Sera · 14 June 1918 Assecondando le vive richieste del Comitato d’azione fra Mutilati invalidi e feriti di guerra di Milano, e del prof. Luchaire e dell’Istituto Francese di Firenze, il Ministro della Guerra francese ha concesso a due valorosi ufficiali mutilati dell’esercito francese di recarsi in Italia perche´ possano esprimere il loro fraterno saluto e la loro fede, durante i giri di propaganda patriottica promossi dal Comitato d’azione italiano fra mutilati. Tra breve altri mutilati verranno in Italia pel medesimo scopo.
Chapter ♥ 10
Cultural Relations Between Italy and France
As was seen in ♥ 9, the French propaganda during the war often used the various means of cultural exchanges between the two countries. These exchanges expanded rapidly during the decade immediately preceding the war. The desire was to act on several sectors of cultural and academic life: travels of professors and students, journals based on the cooperation between Italy and France, foundations of Italian Institutes in France and French Institutes in Italy, propaganda of Italian and French cultures in the different countries. All kinds of disciplines were concerned: philosophy, literature, physiology, and naturally science. Volterra was much involved in this effort (DOCUMENTS ♣ 16–♣ 17).383 We have already mentioned in ♥ 9 his role in the foundation of the Comit´e du Livre and Associazione italiana per l’intesa intellettuale tra i paesi alleati e amici. Obviously, mathematics was not absent from his preoccupations and the correspondence with his French colleagues shows how often Volterra went to Paris for research purposes and Borel, Hadamard and Picard (among others) came to Rome for seminars or scientific collaborations. Borel and Hadamard encouraged their students to spend time in Rome to study with Volterra. In 1912 and 1913, Joseph P´er`es and Ren´e Gateaux had both used the opportunity to do so. In 1915, when Hadamard made a report to claim the attribution of the Francœur Prize of Paris Academy of Sciences to Gateaux, he wrote: “[Gateaux] was among those who, inaugurating a tradition which we could not overestimate, went to Rome to be trained in Volterra’s methods and theories.”384 In 1912, Luchaire had embarked on creating grants in favor of French researchers who wanted to go to Italy. Paolo Savj-Lopez (1878–1919), professor of Latin literature at Catania university and subsequently at Pavia university, during the War served as professeur agr´eg´e at the Sorbonne through an exchange with Maurice Mignon (1882–1962). Mignon was professor of literature at the University of Lyon. He was deeply interested in the destiny of modern Italy; in 1914, he gave a talk in Lyon entitled Latin sympathies in modern Italy.
383
All the documents of this section are contained in Volterra’s Archive, Accademia dei Lincei, Rome.
384
On P´er`es, see ♥ 7, on Gateaux, see the chapter on him in [22].
L. Mazliak, R. Tazzioli, Mathematicians at war, Archimedes 22, C Springer Science+Business Media B.V. 2009 DOI 10.1007/978-90-481-2740-5 10,
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Mignon was introduced to Volterra by Tondeur-Scheffler in a letter dated 24 July 1917 (DOCUMENT ♣ 18). Volterra asked Minister Ruffini to allow Mignon to remain in Italy (DOCUMENT ♣ 19). He mentioned that the project was supported by the Intesa, a short name for the Associazione per l’Intesa intellettuale fra i paesi alleati e amici. Mignon intended to stay in Rome and was afraid to be called back to Lyon after his demobilization. He sent a letter to Volterra on 23 October 1917 (the day of the Italian defeat of Caporetto!) about his conviction that his stay at the University of Rome may participate in the improvement of the relationships between Italy and France. He wrote: “I think that at the moment my duty as a professor is not to eruditely comment on texts, but to participate with words and soul in the improvement of exchanges between the allied countries so that these countries become closer and closer.” Ferrero (see below) asked Volterra385 for a new intervention in favor of Mignon. He also suggested to him to contact the ambassador Barr`ere in the name of the Intesa, and added that Tondeur-Scheffler was “contrariatissimo” (extremely annoyed). Eventually, Mignon stayed and held a series of lectures in Rome on the influence of Italian Rinascimento in France. The contents of the lectures was published in the journal Nuova Antologia.386 In 1918, Mignon became member of the Comit´e du Livre and was strongly involved in spreading French culture abroad. Among other personalities invited to give talks in Rome in 1917, let us also mention the philosopher Lucien L´evy-Bruhl (1857–1939) introduced to Volterra by Luchaire.387 During the 1910s, a constellation of associations and journals dedicated to the Franco-Italian cooperation were created, and we are not able to present a full picture. We have already described the Comit´e du Livre and the Intesa. On July 1912 was founded in Paris the Comit´e France-Italie the president of which was the Senator St´ephen Pichon (1857–1933), the vice-presidents were the politician Jean Louis Barthou (1862–1934), the historian Ernest Lavisse (1842–1922) of the French Academy, the president of the administration council of the Company Paris-LyonM´editerran´ee St´ephane Dervill´e (1848–1925), and Luchaire himself. The purpose of the Committee was “to establish material and moral relations between the two close countries on larger and stronger bases”. The following objectives had to be pursued: i. The development of material relations between Italy and France; ii. To simplify intellectual and moral relations between Italian and French people; iii. In particular, to spread contemporary Italian history and arts in France. The Comit´e France-Italie instituted an Office of economic studies, which followed Italian economic development, and an Office of public relations. Related to
385
Letter from 19 November 1917. Archives of the Accademia dei Lincei.
386
M. Mignon, Critica e Cultura, Nuova Antologia. Rivista di Lettere, Scienze ed Arti, s. 6, vol. 193, 1918, pp. 158–165. 387
Letter from 1 October 1917. Accademia dei Lincei.
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the committee, a journal Revue France-Italie, was created in order to popularize Italian culture in France and to provide information on Italian contemporary politics, economy and social life. A mirror institution, the Comitato Italia-Francia, was instituted in Rome under the direction of the diplomat Marquis Emilio Visconti Venosta (1829–1914) with similar aims.388 Several Institutes of culture were also founded in these years. On the model of Luchaire’s French Institute in Florence, Savj-Lopez founded the Italian Institute of Paris (January 1917). In 1916, Henri Hauvette (1865–1935) founded the Union intellectuelle francoitalienne. Hauvette was a journalist, a writer and a professor of Italian literature at the Sorbonne. He had collaborated with the journal Bulletin italien. The latter had been founded by E. Bouvy in 1901as organ of the Soci´et´e d’´etudes italiennes, created by Charles Dejob (1847–1916) in 1893. In a paper published in 1916,389 Hauvette explained his intentions and pointed out that the Union intellectuelle was interested only in cultural relations and not in other kinds of connections – as trading, industrial and, generally, economic connections. In addition, the Union aimed at spreading Italian contemporary art and literature in France, where generally people only knew classic Italian culture, from Middle Ages to Renaissance. Other journals were created before and during the War with the same aim. Volterra appeared strongly involved in this engagement. The journal Revue des Nations Latines was published in Florence and Paris. It had been founded by Ferrero on the Italian side and by Luchaire on the French side (DOCUMENTS ♣ 12–♣ 15). Guglielmo Ferrero (1871–1942) was an historian who introduced an economic interpretation of ancient history.390 In the opening of the first issue of the Revue des Nations Latines, signed by Ferrero and Luchaire, the anti-German attitude was clearly expressed: Europe has let Germany gain a dominant position in trade, finance, and industry. Stronger cultural
388 Notices on the Comit´e France-Italie and the related Revue can be found in the first pages of the first issue (1913) of Revue France-Italie. 389
H. Hauvette: L’union intellectuelle franco-italienne, Revue internationale de l’Enseignement, 1916, pp. 357–363.
390
Let us observe that as Volterra, Ferrero subsequently opposed to Fascism. In 1930, he escaped to Switzerland and became professor at Geneva university.
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relations between Italy and France can now be used against German economic and financial power. Therefore, the journal had both a cultural and a political aim. The first issue contains a series of papers about the war, and especially on irredentism, the problem of Alsace and Lorraine, the German plan for war, but also papers on intellectual life in France and Italy, economy in the world (a study on the banking systems in Italy and France). Of course some propagandist articles on Latin genius in comparison with German barbarity were published as well. Another of Luchaire’s journals was the Nouvelle Revue d’Italie. He founded it in 1904 and asked French and Italian authors to write (generally in French) on literature, but also politics and history. At the end of the war, the French authorities expressed great confidence in the interest of the allied countries in tightening their cultural links with France. This confidence often lead to an overestimation of this interest, and to a misunderstanding of the local realities and problems. This behaviour recurrently irritated scholars of these countries. To give an example in the Italian mathematical community, let us consider the case of Luigi Bianchi (1856–1928), professor at the Scuola Normale Superiore of Pisa and the author of a classical and celebrated treatise on differential geometry. Bianchi did not agree with a university policy overly obsessed by the Franco-Italian collaboration in a time beset by a host of material problems. In 1920, when Italy suffered from a hard economical crisis, Bianchi was the director of the Scuola Normale – as successor of Ulisse Dini (1845–1918) – and had to face the serious economic problems of the School. He indeed did not receive enough money to buy new books, print dissertations, and so on. On 3 July 1920, in a letter to the philosopher Giovanni Gentile (1875–1944),391 Bianchi complained about the sad situation of the School and wrote: [I]n accordance with the Ministry, some negotiations had started with the Ecole Normale of Paris for a possible exchange of students between the two institutions. And recently, Prof. Mignon, in the name of the French School, has again expressed his desire to set in motion this cooperation. I have answered with a vague and theoretical acceptance, but I postponed the actual realization of the project to a better time. It is not convenient for us to carry on such international exchanges, when we struggle against economic problems and in front of a possible reduction in the number of our students!392
391
Gentile was called by Mussolini in 1922 as minister of Public Education. In 1920 the philosopher Croce was the Minister.
392 Quoted in A. Guerraggio, P. Nastasi (ed. by) Gentile e i matematici italiani, Torino, Bollati Boringhieri, 1993. p. 117
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Document ♣ 12 Advertisement Rivista “Il Mondo Latino” comincera` a pubblicarsi mensilmente il 1o Gennaio 1916 in doppia edizione – italiana e francese. Fondata e redatta da francesi e italiani, la rivista studiera` le questioni piu` gravi che toccano l’una e l’altra nazione e piu` generalmente il mondo latino; cerchera` con una informazione metodica di fare note le cose italiane alla Francia e le cose francesi all’Italia; si sforzer di accrescere i rapporti di ogni genere che intercedono tra i due popoli e di combattere gli influssi germanici che cercano di falsare la comune tradizione latina e minacciano, di qua come di la` dalle Alpi, la vita nazionale nelle sue piu` profonde radici. Il Direttore per l’Italia Il Direttore per la Francia Guglielmo Ferrero Julien Luchaire
Document ♣ 13 Volterra to Ferrero . Roma, n.d. [1916] (draft) Egregio Signore Guglielmo Ferrero. Torino Aderisco col massimo piacere alla Rivista: Il mondo Latino ed approvo pienamente gli scopi per i quali essa viene fondata. sara` anch ben lieto di potervi collaborare pubblicando qualche Articolo. Mi riserbo appena mi sara` possibile di inviarne il soggetto e quando potro` inviarlo.
Document ♣ 14 Luchaire to Volterra . Florence, 11 December 1912 Illustre Signor Senatore, Il nostro amico Giov. Vacca mi fa sapere la Sua cortese accettazione per la nostra futura Revue d’Italie. Sono veramente commosso dalle gentili risposte che ricevo in questi giorni dai migliori scienziati e scrittori italiani; e spero di fare con questa Rivista una cosa buona. L’articolo sulle Matematiche in Italia nella seconda met del sec. XIX (e i primi anni del XX?) sarebbe graditissimo, pur di non apparire come una semplice
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traduzione dell’articolo gi uscito sulla Nuova Antologia. Alla traduzione in francese dell’originale italiano, ci pensiamo noi. Mi creda, Ill. Sig. Senatore, con rispettosa stima Dev.mo J. Luchaire
Document ♣ 15 Volterra to Ferrero . Roma, n.d. [January/February 1916] (draft) Egregio Signore Guglielmo Ferrero Torino Aderisco col massimo piacere alla Rivista: Il mondo Latino ed approvo pienamente gli scopi per i quali essa viene fondata. Saro` anche ben lieto di potervi collaborare pubblicando qualche Articolo. Mi riserbo appena mi sara` possibile di inviarne il soggetto e quando potro` inviarlo.
Document ♣ 16 Luchaire to Volterra . Milano, 16 November 1915
Universite´ de Grenoble Institut Franc¸ais de Florence Bureau de Milan
Illustrissimo e caro Sig. Senatore, Si ricorda che avevamo parlato insieme del progetto di uno scambio di ` Parto ora per Parigi e sarei stato lieto di professori con codesta Universita. poter dire ai nostri amici di laggiu` qualche cosa di concreto in proposito. Se avr qualche notizia da darmi, la prego di scrivermi immediatamente a Parigi, I rue de Fleurus, dove rimarro` fino al 25 di questo mese. Mi creda, illustrissimo e caro Sig. Senatore, coi migliori sentimenti
Il suo dev.mo J. Luchaire
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Document ♣ 17 Volterra to Luchaire . Torino, 13 April 1916 Grand Hotel Ligure e d’Angleterre Carissimo Prof. Luchaire, Abbiamo tuto stabilito col Prof. Hadamard riguardo alle conferenze che egli terra` a Roma dal 1o al 15 Maggio (6 conferenze). Il Ministro della Pubblica Istruzione Italiano d’accordo anche con il Presidente del Consiglio e col Ministro degli Esteri e` ben contento che il Ministero Francese invii il Prof. Hadamard a Roma. Esse costituiscono il primo passo in quella intima unione intellettuale fra la Francia e l’Italia che deve ottenersi collo scambio di insegnanti che Ella ha propugnato sempre con tanto vigore. Il Ministero Italiano inviera` per corrispondere dei professori Italiani in Francia, quando ne avra` il gradimento del Governo Francese. Nell’ultima riunione del Bilancio della Pubblica Istruzione (seduta del 10 Aprile) in seguito a mia interpellanza in proposito il Ministro ha risposto in modo che mi sembra pienamente soddisfacente. [. . . ]
Document ♣ 18 Tondeur-Scheffler to Volterra . Rome, 24 July 1917 ´ ` S. M. le Roi d’Italie Ambassade de la Republique franc¸aise pres ´ Monsieur le Senateur ´ Veuillez me permettre de vous presenter et de vous recommander M. le prof. Mignon, charge´ de cours a` la Faculte´ des lettres de Lyon, actuellement mobilise´ au service de l’attache´ militre . ` au courant et tres ` seduit ´ ´ Il est tres par l’œuvre que nous avons fondee et il vous proposera – en vous priant de vouloir bien l’appuyer de votre haute autorite´ – de faire passer dans la “Nuova Antologia” un article faisant connaˆıtre exactement notre but et nos moyens de l’atteindre. ´ ´ Veuillez agreer, Monsieur le Senateur l’expression de ma haute con´ ´ sideration et de mon devouement. Tondeur-Scheffler
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Document ♣ 19 Volterra to Minister Ruffini . Roma, 14 October 1917 Associazione Italiana per l’intesa intellettuale fra i paesi alleati e amici Eccelenza, Il signor Maurice Mignon professore all Universita` di Lione e che si trova attualmente presso l’Ambasciata francese a Roma ha manifestato il desiderio di tenere un corso di lezioni nella nostra Universita` “Sulle principali epoche della cultura italiana in Francia”. Il signor Mignon ben noto letterato ed ottimo conoscitore della nostra lingua e della nostra letteratura, autore di pregevoli opere, ha anche presentato il programma del suo corso accolto con molto favore dal nostro Consiglio Accademico, il quale ha acconsentito che il corso stesso abbia luogo. La nostra Associazione per l’Intesa Intelletuale fra i paesi alleati ed amici vede con grande compiacimento la proposta fatta del Signor Mignon in quanto essa corrisponde ad uno degli scopi principali dell’Associazione stessa, quello di promuovere la chiamata di Professori stranieri in Italia e di propagare la nostra cultura all’estero. Nel caso particolare del Signor Mignon il tema da lui prescelto per le sue conferenze sulle relazioni letterarie fra la Francia e l’Italia ha un interesse ed un’importanza veramente eccezionale. Interprete dei sentimenti della nostra Associazione ho l’onore di esprimere il voto che la E.V. voglia promuovere sia presso l’Ambasciata Francese in Italia tutti quei passi ad ottenere la permanenza del Professore Mignon in Roma, affinche´ possano aver luogo le sue Conferenze secondo il programma prestabilito ed ho viva speranza che il desiderio manifestato venga esaudito dalla E.V. Col massimo ossequio ho l’onore di dirmi, della E.V., devotissimo
References
1. ALBERS, D, ALEXANDERSON, G and REID, C: International Mathematical Congresses, Springer, 1987 2. ANIZAN, Anne-Laure: Paul Painlev´e, un scientifique en politique, Th`ese de l’Institut d’Etudes Politiques, 2006 3. AUBIN, David et BRET, Patrice: Le Sabre et l’Eprouvette: l’invention d’une science de guerre. Centre de recherche de l’Historial de P´eronne, Agn`es Vi´enot e´ ditions, 2003 4. AUDOIN-ROUZEAU, St´ephane et BECKER, Jean-Jacques (eds): Encyclop´edie de la Grande Guerre, Bayard, 2004 5. BANSAT-BOUDON, Lyne and LARDINOIS, Roland (eds): Sylvain L´evi (1863–1935): e´ tudes indiennes, histoire sociale: actes du colloque tenu a` Paris les 8–10 octobre 2003, publi´es sous la direction de Lyne Bansat-Boudon et Roland Lardinois; avec la collaboration d’Isabelle Rati´e, Brepols, 2007 6. BARBUT, Marc, LOCKER, Bernard et MAZLIAK, Laurent: Paul L´evy-Maurice Fr´echet, 50 ans de correspondance math´ematique, Hermann, 2004 7. BARBUT, Marc and MAZLIAK, Laurent: Commentary on the notes for Paul L´evy’s 1919 lectures, JEHPS, vol. 4, 1, 2008 8. BOREL, Emile: Œuvres, Editions du CNRS, 1972 9. BOREL, Emile: Le Hasard, F´elix Alcan, 1914 10. BRU Bernard, BRU, Marie-France and Kai Lai CHUNG: Borel and Saint-Petersburgh martingale, JEHPS, Vol. 5, 1, 2009 (originally published in French in 1999 in Revue d’Histoire des Math´ematiques) 11. BRUTI LIBERATI, Luigi: Il clero italiano nella grande guerra, Roma, Editori Riuniti, 1982 12. CHARLE, Christophe: Les professeurs de la facult´e des lettres de Paris, Editions du CNRS, 1986 13. DUBREIL, Pierre: L’alg`ebre en France de 1900 a` 1935, Cahiers du S´eminaire d’histoire des math´ematiques, 3, 1982 14. DUGAC, Pierre: Les lendemains de l’Int´egrale. Henri Lebesgue: lettres a` Emile Borel, Vuibert, 2004 15. FILIPPI, G: Le Universit`a e gl’Istituti d’istruzione superiore in Italia durante la guerra, Bollettino Ufficiale del Ministero della Pubblica Istruzione, a. XLVII (1920), pp. 329–384 16. FONTANON, Claudine et FRANCK (eds): Paul Painlev´e (1863–1933), Un savant en politique. Actes de la journ´ee d’´etude au CNAM le 22 mai 2003. Presses Universitaires de Rennes, 2005 17. FONTANON, Claudine et GRELON, Andr´e (eds): Les professeurs du Cnam. Dictionnaire biographique (1795–1955), INRP/CNAM, 1994 18. GALVEZ-BEHAR, Gabriel: Le savant, l’inventeur et le politique. Le rˆole du sous-secr´etariat d’´etat aux inventions durant la Premi`ere Guerre Mondiale, Vingti`eme Si`ecle. Revue d’Histoire, 85, Janvier–Mars 2005, pp. 103–117 19. GIBELLI, A: La grande guerra degli italiani. 1915–1918, 2 Vols., Milano, BUR, 2007 L. Mazliak, R. Tazzioli, Mathematicians at war, Archimedes 22, C Springer Science+Business Media B.V. 2009 DOI 10.1007/978-90-481-2740-5 BM2,
189
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References
20. GILBERT, M: La grande storia della prima guerra mondiale, Milano, Mondadori, 2000 21. GOLDSTEIN, Catherine and GRAY, Jeremy (eds): Changes Brought by WWI on Places of Mathematics. To appear 22. GOLDSTEIN, Catherine et MAZLIAK, Laurent (eds): Trajectoires de math´ematiciens franc¸ais autour de la Premi`ere Guerre Mondiale. To appear 23. GOODSTEIN, Judith R: The Volterra chronicles: the life and times of an extraordinary mathematician (1860–1940), History of Mathematics, American Mathematical Society & London Mathematical Society, 2007 24. GUERRAGGIO, Angelo e PAOLONI, Giovanni: Vito Volterra. Biografie, Franco Muzzio Editore, 2008 25. GUILLEN, Pierre (ed): La France et l’Italie pendant la Premi`ere Guerre Mondiale. Actes du Colloque international organis´e par le centre d’´etude des mondes Alpins et Italiens, Universit´e de Grenoble, 28–30 September 1973. Presses Universitaires de Grenoble, 1976 26. GUIRALDENQ, Pierre: Emile Borel. L’espace et le temps d’une vie sur deux si`ecles, Distribution Librairie Blanchard, 1999 27. HADAMARD, Jacques: Œuvres, Editions du CNRS, 1968 ˇ SMA, ˇ 28. HAVLOVA, Veronika, MAZLIAK, Laurent and SI Pavel: Le d´ebut des relations math´ematiques franco-tch´ecoslovaques vu a` travers la correspondance Hostinsky-Fr´echet, JEHPS, Vol. 1, 1, 2005 29. HAWKINS, T: Lebesgue’s Theory of Integration, its Origins and Development. American Mathematical Society, 1970 30. ISNENGHI, M: Il mito della grande guerra, Bologna, Il Mulino, 1970; second ed., 2007. 31. KOLMOGOROV, Andrei N.: Grundbegriffe der Warscheinlichkeitsrechnung, Springer, 1933 32. LANDAU, Philippe-E: L’Alliance Franco-Russe: un dilemme? in Philippe-E. Landau: Les Juifs de France et la Grande Guerre, CNRS-Editions, Paris, 1999. 33. LANDAU Philippe-E: Les Juifs russes a` Paris pendant la Grande Guerre, cibles de l’antis´emitisme, Archives juives 2001/2, 34, 2002 34. LEHTO, O: Mathematics without Borders: A History of the International Mathematical Union, Springer, 1998. 35. LINGUERRI, S: Vito Volterra e il Comitato Talassografico Italiano. Imprese per aria e per mare nell’Italia unita (1883–1930), Firenze, Olschki, 2005 36. LINGUERRI, S. e SIMILI, R.: Volterra, Marconi e il Consiglio Nazionale delle Ricerche in CASELLA, A., FERRARESI, A., GIULIANI, G., SIGNORI, E. (a cura di): Una dificile modernit`a. Tradizioni di ricerca e continuit`a scientifiche in ltalia 1890–1940 (Pavia, La Goliardica Pavese, 2000), pp. 105–132 37. LUCHAIRE, Julien: Confessions d’un franc¸ais moyen, Sagittaire, Marseille, 1943. Second and Completed edition by Leo. S. Olschki, Florence, 1965 38. MAC MILLAN, Margaret: Peacemakers, J. Murray, 2001 39. MARBO, Camille: A travers deux si`ecles, souvenirs et rencontres (1883–1967), Grasset, 1967 40. MAYLENDER, M: Storia delle Accademie d’Italia, 5 Vols., Bologna, L. Cappelli, 1926–1930 41. MAZLIAK, Laurent: Borel, Probability and La Revue du Mois, JEHPS, Vol. 3, 1; 2007 42. MAZLIAK, Laurent and SHAFER, Glenn: Why did the Germans arrest and release Emile Borel in 1941? 43. MAZYA Vladimir and SHAPOSHNIKOVA, Tamara: Jacques Hadamard, a Universal Mathematician, Oxford University Press, 1998 44. NASTASI, Pietro eTAZZIOLI, Rossana (ed.): Aspetti scientifici e umani nella corrispondenza di Tullio Levi-Civita (1873–1941), Quaderni Pristem n. 12, 2000, Palermo 45. PANCALDI, G., Vito Volterra: Cosmopolitan ideals and nationality in the italian scientific community between Belle Epoque and the First World War, Minerva, 31, 1993, pp. 21–37 46. PAOLONI, Giovanni: Vito Volterra e il suo tempo (1860–1940), Catalogo della Mostra storico-documentaria, Roma, 1990 47. PICARD, Emile: Œuvres, Editions du CNRS, 1978 48. RECHTER, David: The Jews of Vienna and the First World War, Littman Library of Jewish Civilization, London, 2001
Mathematicians at war
191
49. ROMANO, Sergio: Libera Chiesa. Libero Stato?, Milano, Tea, 2005 50. ROUSSEL, Yves: L’histoire d’une politique des inventions 1887–1918, Cahiers pour l’histoire du CNRS 1939–1989, Cahier 1989-3 51. RUSCONI, Gian Enrico: L’azzardo del 1915, Coll. Intersezioni, Il Mulino, 2005 52. Conseil International de Recherches 1919, Vol. I. Constitutive Assembly held at Brussels, 18–28 July 1919. Report and Proceedings edited by Sir Arthur Schuster, General Secretary, London, Harrison, 1920 53. SIMILI, Raffaella (ed): Scienza, tecnologia e istituzioni in Europa. Vito Volterra e l’origine del CNR, Laterza, 1993 54. SOLZHENITSYN, Aleksandr I: Deux si`ecles ensemble. Fayard, 2003 55. SZAJKOWSKI, Zosa: Jews, Wars and Communism. Vol. I: The Attitude of American Jews to World War I, the Russian Revolutions of 1917, and Communism (1914–1945). Ktav Publishing House, 1972 56. VILLAT, Henri: Comptes-Rendus du Cong`es International des Math´ematiciens, Publi´es par H. Villat, Toulouse, 1921 57. VOLTERRA, Vito: Opere matematiche: memorie e note. Accademia dei Lincei, 1954–1962 58. World War I, Encyclopaedia Britannica, 2008
Index
A Abetti, 103 Alcan, 122 Alessio, 150 Amalgi`a Volterra, 78, 79 Angelitti, 150 Appell, 35, 143, 145 Appell, Pierre, 118
De la Vall´ee Poussin, 142 De Marchi, 53, 74 Debr´e, 57, 94 Deschasnel, 141 Dini, 159 Duchesne, 73, 82 Dunoyer, 36, 38, 49, 55, 56, 61, 69 Durkheim, 168
B Basch, 168 Beltrami, 75, 101 Benoist, 69, 84 Bianchi, 145 Boccard, 150 Boccardi, 150 Bo¨ıto, 75, 100 Boselli, 53, 74, 100, 101 Boutroux, 37, 41, 43, 129, 132 Brachet, 136 Breton, 119, 122, 124, 127 Briand, 73 Buisson, 122, 124
F Fano, 89 Fergola, 152 Ferrari, 76 Ferrero, 47, 76 Filloux, 117
C Camera, 150 Cassinis, 151 Castelnuovo, 89, 91 Celoria, 151 Ciani, 53 Cimbali, 43 D D’Ovidio, 53, 74 Da Schio, 151 Danjon, 104, 107, 108, 111–113, 116 Darboux, 112, 115 de Broglie, 98 De Filippi, 167
G Gallo, 109 Gascouin, 90 Gateaux, 37, 41, 43, 46–48, 58, 158 Gauthier Villars, 122 Gevrey, 85 Giordano, 96, 97, 121, 122, 125 Girard, 129 Greenish, 136 H Hagen, 149, 150 Honnorat, 144 I Imbart de la Tour, 61, 70, 73, 81, 82, 86, 101, 102 K Kelvin, 140 Kœnigs, 139, 140
193
194 L Langevin, 108, 138 Lebeau, 65 Leclerc, 64 Lecointe, 146 Leoncavallo, 75, 100 L´evi, 81 L´evi, Isra¨el, 168 L´evy, Paul, 37 L´evy, Paul, 85 Lorenzoni, 152 Luchaire, 65, 84, 144 Luzzatti, 76, 100 M Maffi, 76, 150 Marcolongo, 53 Marconi, 76, 100 Maspero, 92 Maurain, 123, 125, 143 Meda, 73, 76 Milhaud, 108 Millosevich, 74, 100, 101 Moneta, 48 Monteverde, 75, 100 Morello, 41 N Netter, 168 Nyrop, 136
Index Reina, 91 Reinach, 168 Ricci, 75 Ricc`o, 149, 152 Richet, 42, 57 Righi, 75, 100 Robin, 128 Rotschild, 168 Ruffini, 74, 100 S Salandra, 83, 132 Sartre, 142, 144 Schiaparelli, 152 Schuster, 134, 147, 149 S´ee, 168 Sella, 91 Smith, 65 Somigliana, 53, 74 Sonnino, 83, 105, 106 Soula, 46, 58, 64 Stringher, 75 T Tamassia, 53, 74 Tondeur-Scheffler, 92 Tonelli, 72, 75 Toniolo, 75, 100 Toussaint, 143 Tringali, 152
P Paci, 150 Painlev´e, 68, 70, 95, 96, 105–107, 109–111, 127, 143 Percin, 49 P´er`es, 37, 41, 43, 57, 59, 128, 142 P´etain, 124 Pigorini, 100, 101 Pirogini, 74 Poincar´e, Raymond, 104 Pollock, 136
V Van den Heuvel, 55, 73 Veronese, 53 Viaro, 151 Villari, 100 Villey, 36
R Rajna, 149, 152
Z Zappa, 151
W Wahl, 168 Wilson, 133 Wolf, 168
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