THE MOTIVE POWER OF HEAT. 



127 



late the mechanical equivalent and to plan the very experiments since 

 carried out by later workers. To give emphasis to this statement, we 

 have but to consider the following translation of his own words : 



Heat is nothing else than motive power, or rather, motion which has 

 changed its form. It is a movement of the particles of a body. Wherever 

 there is a destruction of motive power, there is at the same time the production 

 of a quantity of heat precisely proportional to the quantity of motive power 

 destroyed. Reciprocally, wherever there is destruction of heat, there is the 

 production of motive power. 



We can lay down the general proposition that motive power is a quantity 





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Facsimile of a Page of Carnot's Note-book Relative to the Transformation of 

 Heat into Motive Power, containing a valuation (the first known to be made) of the so. 

 called " mechanical equivalent of heat." This estimate gives for the mechanical equivalent 

 of heat 370 kilogram-meters, which is nearer the correct value (^20, Rowland) than Mayer's 

 later determination (365). 



