III. 



REFLECTIONS ON THE MOTIVE-POWER OF 

 HEAT, AND ON MACHINES FITTED TO 

 DEVELOP THAT POWER.* 



BY S. CARNOT. 



EVERY one knows that heat can produce motion. 

 That it x possesses vast motive-power no one can 

 doubt, in these days when the steam-engine is 

 everywhere so well known. 



To heat also are due the vast movements which 

 take place on the earth. It causes the agitations 

 of the atmosphere, the ascension of clouds, the fall 

 of rain and of meteors, the currents of water which 

 channel the surface of the globe, and of which 



* Sadi Carnot's Reflexions sur la puissance motrice du 

 feu (Paris, Bachelier 1824) was long ago completely ex- 

 hausted. As but a small number of copies were printed, 

 this remarkable work remained long unknown to the 

 earlier writers on Thermodynamics. It was therefore for 

 the benefit of savants unable to study a work out of print, 

 as well as to render honor to the memory of Sadi Carnot, 

 that the new publishers of the Annales Scientifique de 

 VEcole Normale superieure (ii. series, 1. 1, 1872) published a 

 new edition, from which this translation is reproduced. 



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