114 SEVENTH DETERMINATION OF EQUIVALENT. 



theory of gases as well as the quantitative dynamical 

 theory of heat 



At the British Association in 1848, Joule communicated 

 the result of further experiments made for the equivalent, 

 with a slight alteration in the apparatus calculated to give 

 greater exactness to the results. The result arrived at 

 being 771, "which is," he says, "believed to be within one 

 two hundredth part of the truth." This it is found to be. 



Joule published nothing further in 1848 or 1849, but 

 during this interval he was occupied in making his final 

 investigation, with his now perfected apparatus, on the 

 mechanical equivalent of heat. 



In the meantime,, events were occuring in other places, 

 which, as being directly connected with the recognition of 

 the truth and importance of Joule's work, require notice in 

 this memoir. 



