72 A Century of Science 



the initiative. It is doubtful if men of eminent 

 ability are ever made so by schooling. The school 

 offers opportunities, but in such men the tendency 

 to the initiative is so strong that if opportunities 

 are not offered they will somehow contrive to 

 create them. When Edward Youmans was about 

 thirteen years old he persuaded his father to buy 

 him a copy of Comstock's Natural Philosophy. 

 This book he studied at home by himself, and re- 

 peated many of the experiments with apparatus of 

 his own contriving. When he made a centrifugal 

 water wheel, and explained to the men and boys 

 of the neighbourhood the principle of its revolution 

 in a direction opposite to that of the stream which 

 moved it, we may regard it as his earliest attempt 

 at giving scientific lectures. It was natural that 

 one who had become interested in physics should 

 wish to study chemistry. The teacher (who was 

 not " Uncle Good " ) had never so much as laid 

 eyes on a textbook of chemistry ; but Edward 

 was not to be daunted by such trifles. A copy of 

 Comstock's manual was procured, another pupil 

 was found willing to join in the study, and this 

 class of two proceeded to learn -what they could 

 from reading the book, while the teacher asked 

 them the printed questions, those questions the 

 mere existence of which in textbooks is apt to 



