2 7 o THE POPULAR SCIENCE MONTHLY 



all the coaches you have met in the course of the day, but you hear 

 them, you do not see the figures. This is one of the most remarkable 

 peculiarities of your brain, and I venture to note it because I have 

 the unanimous testimony for it of those who know you most intimately. 



At the lycee of Nancy, you were superior to your comrades in every 

 branch, and you seemed so well endowed for literary studies that one of 

 your teachers, who is one of our best historians, would have been glad 

 to attract you to our speciality; but when, in the fourth grade, you 

 opened a text on geometry, the work was done. Your astonished 

 teacher rushed to your mother and said to her : " Madam, your son will 

 be a mathematician." And she was not particularly frightened. Math- 

 ematics, as soon as you made her acquaintance, seized you and held 

 you. She is a tenacious mistress, with this peculiarity, that she fires all 

 her lovers with the same impulse: the mathematician is a peripatetic. 

 Pedestrian exercise seems necessary to him in order to stimulate 

 thought, and, as he walks, certain mechanical gestures with which he 

 occupies his fingers seem the indispensable auxiliaries of an intellectual 

 labor that leaves him indifferent to the exterior world and even uncon- 

 scious of it. One day, when promenading, you suddenly discovered 

 that you were carrying in your hand a wicker cage. You were prodig- 

 iously surprised. When, where, how had your hand plucked this cage, 

 which was new and fortunately empty? You had no idea, and re- 

 tracing your steps, you walked until you found on the sidewalk the 

 stock of a basket-maker whom you had innocently despoiled. Such 

 phenomena are very common with you ; they will become, if they are not 

 already so, as celebrated as those attributed to Lagrange, to Kant, to 

 Ampere. You might be in worse company. 



You were, nevertheless, at times, a child who liked pleasure and 

 games, but you invented your own amusements. You played at rail- 

 road or diligence with a map or a guide in reach, and thus you learned 

 geography. You put history into dramas and comedies; at sixteen 

 years you had written a five-act tragedy in verse, and you would not 

 have been a son of Lorraine if the heroine had not been Joan of Arc. 

 Even charades had a charm for you. Are they not problems? 



The war interrupted these games. You were sixteen years old ; your 

 age and your health prevented your mingling with the combatants, but 

 you tried to make yourself useful; every day you accompanied your 

 father to the hospital and served as his secretary; you were so eager to 

 learn the news that, in order to read them in the only papers that were 

 accessible to you, you learned German. The war must have matured 

 you; it certainly left its trace upon you; but it did not change your 

 life. To the men of the generation preceding yours, it brought a defi- 

 nite conversion with introspection. You have read Sully-Prudhomme's 

 verses entitled " Eepentance." In them he confesses the error into 

 which the generosity of his heart had drawn him and in which the fal- 



