OF THE 



UNIVERSITY 



APPENDIX B. 



CARNOT'S FOOT-NOTES. 



NOTE A. The objection may perhaps be raised 

 here, that perpetual motion, demonstrated to be 

 impossible by mechanical action alone, may pos- 

 sibly not be so if the power either of heat or elec- 

 tricity be exerted; but is it possible to conceive 

 the phenomena of heat and electricity as due to 

 anything else than some kind of motion of the 

 body, and as such should they not be subjected to 

 the general laws of mechanics ? Do we not know 

 besides, a posteriori, that all the attempts made to 

 produce perpetual motion by any means whatever 

 have been fruitless ? that we have never succeeded 

 in producing a motion veritably perpetual, that 

 is, a motion which will continue forever without 

 alteration in the bodies set to work to accomplish 

 it ? The electromotor apparatus (the pile of Volta) 

 has sometimes been regarded as capable of pro- 

 ducing perpetual motion ; attempts 'have been 

 made to realize this idea by constructing dry piles 

 said to be unchangeable ; but however it has been 

 done, the apparatus has always exhibited sensible 



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