xii NOTE BY THE EDITOR. 



more firmly and closely those bonds of kindly 

 thought and feeling which are growing continually 

 more numerous and stronger as the nations are 

 brought to see that humanity is larger and more 

 important than political divisions, and that the 

 labors of educated men and of the guiding minds 

 in the great industries are constantly doing more 

 to promote a true brotherhood of mankind inan 

 ever have, or ever can, the greatest statesmen. 



When the wonderful intellectual accomplish-- 

 menis of men like the elder Sadi Carnot become 

 known and appreciated by the world, much more 

 will have been accomplished in tliis direction. It 

 is perhaps from this point of view that the impor- 

 tance of such work will be most fully recognized. 

 When the little treatise which is here for the first 

 time published in English becomes familiar to 

 those for whom it is intended, it will be, to many 

 at least, a matter of surprise no less than pleasure 

 to discover that France has produced a writer on 

 this now familiar subject whose inspiration antici- 

 pated many of the principles that those founders 

 of the modern science, Eankine and Clausius, 

 worked out through the tedious and difficult 

 methods of the higher mathematics, and which 

 were hailed by their contemporaries as marvellous 

 discoveries. 



