606 FRA G HUNTS OF SCIENCE. 



By turning the handle of a magneto-electric machine a 

 coil of wire may be caused to rotate between the poles of a 

 magnet. As long as the two ends of the coil are uncon- 

 nected we have simply to overcome the ordinary inertia and 

 friction of the machine in turning the handle. But the 

 moment the two ends of the coil are united by a thin 

 platinum wire a sudden addition of labor is thrown upon 

 the turning arm. When the necessary labor is expended, 

 its equivalent immediately appears. The platinum wire 

 glows. You can readily maintain it at a white heat, or 

 even fuse it. This is a very remarkable result. From the 

 muscles of the arm, with a temperature of 100 degrees, we 

 extract the temperature of molten platinum, which is 

 nearly four thousand degrees. The miracle here is the 

 reverse of that of the burning bush mentioned in Exodus. 

 There the bush burned, but was not consumed: here the 

 body is consumed, but does not burn. The similarity of 

 the action with that of the voltaic battery when it heats 

 an external wire is too obvious to need pointing out. 

 When the machine is used to decompose water, the heat of 

 the muscle, like that of the battery, is consumed in molec- 

 ular work, being fully restored when the gases recombine. 

 As before, also, the transmuted heat of the muscles may 

 be bottled up, carried to the polar regions, and there 

 restored to its pristine form. 



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 voltaic battery is the animal body a creator 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 creative power. 

 Compared with the notions previously entertained regard- 

 ing the play of " vital force" this is a great result. The 

 problem of vital dynamics has been described by a com- 

 petent authority as "the grandest of all." I subscribe to 

 this opinion, and honor correspondingly the man who first 

 successfully grappled with the problem. He \vas 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 connection with 

 our illustrious countryman Dr. Joule. Other eminent 



