438 FRAGMENTS OF SCIENCE. 



low the theory into its most abstruse and impressive 

 applications. With their places reversed, however, 

 Joule might have become Mayer, and Mayer might 

 have become Joule. 



It does not lie within the scope of these brief arti- 

 cles to enter upon the developments of the Dynamical 

 Theory accomplished since Joule and Mayer executed 

 their memorable labours. 



