MAHLER'S CALORIMETER. 

 The data obtained are as follows: 



Difference of temperature 25.14 22.04 = 3.100 



Correction for minutes (9, 8), (8, 7), (7, 6). . 0.015 X 3 = 0.045 



44 44 | minute (5, 6) =0.005 



" i " (5, 5*) =0.001 



Corrected temperature difference 

 Then, 



Total heat developed 3.15 3.15 X 2.681 = 



From this subtract 



Heat due to naphthalin 0.034 X 9692 = 0.3295 



44 44 4I iron wire 0.025 X 1.6 =0.04 



HNO 3 0.08 X 0.23 =0.0184 



3.151 



8.4451 



0.3879 



Heat developed by the combustion of the coke 8.0572 



or 8057.2 per kilogram, or 14503 B. T. U. 



When the combustible tested contains hydrogen, it must 

 be remembered that, while the gas in the bomb is dry at the 

 beginning, it is saturated at the close of the experiment. In 

 reality, the latent heat of vaporization of the small quantity 

 of water necessary to be added is inconsiderable. The mean 

 of several tests was 5 in 8500 calories observed, or only 

 T J__. Still, when we test gases, which cause less marked 

 difference in temperature than solids or liquids, we must allow 

 for this heat of vaporization to be exact. 



It may be asked if any allowance will be made for the 

 heat of the electric current at the moment of kindling. The 



