S66 FRAGMENTS OF SCIENCE 



The matter of the human body is the same as that of 

 the world around us; and here we find the forces of the 

 human body identical with those of inorganic nature. Just 

 as little as the Yoltaic battery is the animal body a cre- 

 ator of force. It is an apparatus exquisite and effectual 

 beyond all others in transforming and distributing the 

 energy with which it is supplied, but it possesses no crea- 

 tive power. Compared with the notions previously enter- 

 tained regarding the play of '* vital force" this is a great 

 result. The problem of vital dynamics has been described 

 by a competent authority as "the grandest of all." I sub- 

 scribe to this opinion, and honor correspondingly the man 

 who first successfully grappled with the problem. He was 

 no pope, in the sense of being infallible, but he was a 

 man of genius whose work will be held in honor as long 

 as science endures. I have already named him in connec- 

 tion with our illustrious countryman. Dr. Joule. Other 

 eminent men took up this subject subsequently and inde- 

 pendently, but all that has been done hitherto enhances 

 instead of diminishing the merits of Dr. Mayer. 



Consider the vigor of his reasoning. "Beyond the 

 power of generating internal heat, the animal organism 

 can generate heat external to itself. A blacksmith by 

 hammering can warm a nail, and a savage by friction can 

 heat wood to its point of ignition. Unless, then, we aban- 

 don the physiological axiom that the animal body cannot 

 create heat out of nothing, we are driven to the conclu- 

 sion that it is the total heat, within and without, that ought 

 to he regarded as the real calorific effect of the oxidation, 

 within the hody.^^ Mayer, however, not only states the 

 principle, but illustrates numerically the transfer of mus- 

 cular heat to external space. A bowler who imparts a 



