X. — Note on the employment of Electrical 

 Currents, for ascertaining the Specif c Heat 

 of Bodies. By J. P. Joule, Esq. 



(Read July 13th, 1847.) 



Having recently had occasion to ascertain the 

 specific heat of sperm oil, I employed for the 

 purpose the new method described in the Seventh 

 Volume, New Series, of the Memoirs of this 

 Society. Two platinum wires, each four inches 

 long and rooth of an inch in diameter, were 

 immersed, one in a known quantity of water, 

 and the other in the sperm oil. A powerful 

 current of electricity from six large constant 

 cells, was then transmitted through the wires for 

 half an hour, and the increase of the temperature 

 of the water and oil noted. The specific heat of 

 the sperm oil arrived at was 0.3757, a result 

 so much lower than that of Dalton, that I was 

 led to examine whether I had fallen into any 



