William Herschel, born in 1738, at the outbreak of the Seven Years' War, when he was eighteen, was a performer in the regimental band, and after a battle passed a night in a ditch and escaped in disguise, to England, where he eked out a precarious livelihood by teaching music. He supported himself until middle age as an organist. In much of his later work he was greatly aided by his sister Caroline. When he discovered a sixth planet he became famous, and devoted himself exclusively to astronomy, training his only son to follow in his footsteps, and dying in 1822.
Agassiz[19] at twelve had developed a mania for collecting. He memorized Latin names, of which he accumulated "great volumes of MSS.", and "modestly expressed the hope that in time he might be able to give the name of every known animal." At fourteen he revolted at mercantile life, for which he was designed, and issued a manifesto planning to spend four years at a Cermem university, then in Paris, when he could begin to write. Rooks were scarce, and a little later he copied, with the aid of his brother, several large volumes, and had fifty live birds in his room at one time.
At twelve Huxley[20] became an omnivorous reader, and two or three years later devoured Hamilton's Logic and became deeply interested in metaphysics. At fourteen he saw and participated in his first post-mortem examination, was left in a strange state of apathy by it, and dates his life-long dyspepsia to this experience. His training was irregular; he taught himself German with a book in one hand while he made hay with the other; speculated about the basis of matter, soul, and their relations, on radicalism and conservatism; and reproached himself that he did not work and get on enough. At seventeen he attempted a comprehensive classification of human knowledge, and having finished his survey, resolved to master the topics one after another, striking them out from his table with ink as soon us they were done. "May the list soon get black, although at present I shall hardly be able, I am afraid, to spot the paper." Beneath the top skimmings of these years he afterward conceived seething depths working beneath the froth, but could give hardly any account of it. He undertook the practise of pharmacy, etc.