[Footnote 10: Unpublished notes by Abbé Chesnais.]

His tendency, after taking his bachelor's degree, was towards science;
he was ambitious to enter the École polytechnique, and joined the
special mathematics class. Even when very young he had shown particular
aptitude for mechanics, and a gift for invention which we have seen
exercised in his practical jokes as a student. When he was only four or
five years old he constructed a bed out of paper, which he raised by
means of cords and pulleys.

"He passed whole hours," says his Stanislas classmate, Lieutenant
Constantin, "in trying to solve a mathematical problem, or studying some
question which had interested him, without knowing what went on around
him; but as soon as he had solved his problem, or learned something new,
he was satisfied and returned to the present. He was particularly
interested in everything connected with the sciences. His greatest
pleasure was to make experiments in physics or chemistry: he tried
everything which his imagination suggested. Once he happened to produce
a detonating mixture which made a formidable explosion, but nothing was
broken except a few windows."

His choice of reading revealed the same tendency. He was not fond of
reading, and only liked books of adventure which were food for his
warlike sentiments and his ideas of honor and honesty. He preferred the
works of Major Driant, and re-read them even during his mathematical
year. Returning from a walk one Thursday evening, he knocked on the
prefect's door to ask for a book. He wanted _La Guerre fatale_, _La
Guerre de Demain_, _L'Aviateur du Pacifique_, etc. "But you have already
read them." "That does not matter." Did he really re-read them? His