1895.] The Latent Heat of Evaporation of Water. 



Table VI. 



221 



Comparison between Regnault's Experimental Results (R tf ) over the 

 range 63 to 88, with the value given by formulae (R), (W), 

 and (G 2 ). 



We thus see that formula (G) gives a closer approximation to 

 Regnault's experimental results over the above range than either of 

 the other formulae. 



Again, the results of my earlier experiments, referred to above, 

 lend support to formula (G). 



One difficulty, however, presents itself. If there is any truth in 

 the ordinarily accepted ratio of the "mean thermal unit from 100 

 to " to the " thermal unit at 15 C.," then, so far from my own, 

 Dieterici's, and Regnault's results being in agreement, they in reality 

 differ considerably, for our values are expressed in different units. 

 True, Regnault adopted the " thermal unit at 15," but, as his experi- 



