NOTE TO SECOND EDITION. 



THE present edition of this little work is im- 

 proved by the removal of a few errata observed in 

 the first issue, and by the addition of a recent and 

 excellent portrait of Lord Kelvin, as a frontispiece 

 to his era-making paper, at page 127. This pic- 

 ture, taken within the last year, is thought by the 

 friends of its distinguished subject to be one of the 

 best yet produced. That it is satisfactory to him 

 and his friends is indicated by the fact that the 

 original of this reproduction was presented to the 

 writer by Lady Kelvin, in 1895, immediately after 

 it was taken, and the autograph supplied by her 

 distinguished husband. The Editor takes this 

 occasion to acknowledge cordially the letters of 

 appreciation and commendation received from 

 those who have agreed with M. Haton de la Gou- 

 pilliere that the translation of Carnot and its 

 publication in this manner, with the famous paper 

 of Lord Kelvin, will be considered as worthy of 

 approval by English-speaking readers as well as 

 "appreciated by the whole French nation." 



xiii 



