n8 POPULAR SCIENCE MONTHLY. 



well known and acknowledged to need recounting here. We wish 

 merely to call to mind one upon whose theoretical deductions all the 

 advances in the science of thermodynamics since his day have been 

 based: Sadi Carnot, a young French military engineer. 



Appreciation of genius is a mark of the civilization and culture 

 of a people, and the world can ill afford to neglect the memory not only 

 of the men who by practical application have helped to make that 

 civilization possible, but also of those who by theoretical deduction 

 have pointed out the way of progress. The world must needs remem- 

 ber those by whose brain power, as Mr. Fernald says, we have been 



Nicholas Leonard Sadi Carnot (179G-1832), Father of the Science of Thermodynamics. 



enabled to cross the gulf of fire to the paradise of invention and 

 achievement that lies beyond, of which none can see the farther bound. 

 Every schoolboy knows of James Watt, of the Stephensons and their 

 'Eocket,' but who, save the special student, has ever heard of Sadi 

 Carnot ? 



Watt made his great improvements in the steam engine (really 

 almost invented it) during the last quarter of the eighteenth century. 

 But for the next fifty years, including those covered by the life of 

 Carnot, the development was seemingly the result of chance. The 



