FORCE. 381 



In 1845 he published his memoir on * Organic 

 Motion,' and applied the mechanical theory of heat 

 in the most fearless and precise manner to vital 

 processes. He also embraced the other natural agents 

 in his chain of conservation. In 1853 Mr. Water- 

 ston proposed, independently, the meteoric theory 

 of the sun's heat, and in 1854 Professor William 

 Thomson applied his admirable mathematical powers 

 to the development of the theory ; but six years pre- 

 viously the subject had been handled in a masterly 

 manner by Mayer, and all that I have said about it has 

 been derived from him. When we consider the cir- 

 cumstances of Mayer's life, and the period at which he 

 wrote, we cannot fail to be struck with astonishment at 

 what he has accomplished. Here was a man of genius 

 working in silence, animated solely by a love of his 

 subject, and arriving at the most important results in 

 advance of those whose lives were entirely devoted to 

 Natural Philosophy. It was the accident of bleeding a 

 feverish patient at Java in 1840 that led Mayer to 

 speculate on these subjects. He noticed that the venous 

 blood in the tropics was of a brighter red than in colder 

 latitudes, and his reasoning on this fact led him into 

 the laboratory of natural forces, where he has worked 

 with such signal ability and success. Well, you will 

 desire to know what has become of this man. His 

 mind, it is alleged, gave way ; it is said he became in- 

 sane, and he was certainly sent to a lunatic asylum. In a 

 biographical dictionary of his country it is stated that 

 he died there, but this is incorrect. He recovered; 

 and, I believe, is at this moment a cultivator of 

 vineyards in Heilbronn. 



