130 PROCEEDINGS OF THE AMERICAN ACADEMY 



The close agreement of these with the estimated amount is, of 

 course, only accidental, for they depend upon an estimation of only 

 0°.08 and 0°.12 respectively. But they at least show that the 

 water is delivered into the calorimeter without much change of 

 temperature. 



A few experiments were made as follows between ordinary tempera- 

 tures and 100°, seeing that this has already been determined by Reg- 

 nault. 



Two thermometers were placed in the calorimeter, the temperature 

 of which was about 5° below that of the atmosphere. The vessel B 

 was then filled, and the water let into the calorimeter, by which the 

 temperature was nearly brought to that of the atmosphere ; the opera- 

 tion was then immediately repeated, by which the temperature rose 

 about 5° above the atmosphere. The temperature of the boiling 

 water was given by a thermometer whose 100° was taken several 

 times. 



As only the rise of temperature is needed, the zero points of the 

 thermometers in the calorimeter are unnecessary, except to know that 

 they are within 0°.02 of correct. 



June 18. 



Temperature of boiling water, 99°. 9. 



Calor. before 2G84.7 ; temperat. 259.2 by 6166, and 248.3 by 6165. 

 " after 2993.2; " 381.0 « " 363.4 " 



259.3 = 18°.5G8, or 18°.555 when corrected for stem. 



218.3 = 18°.564, or 18°.551 " " 

 381.0 = 28°.054, or 28°.065 



363.4 = 28°.055, or 28°,066 " " 



Specific heat 2 8° — 10 0° _ 

 "Specific" heat 18° — 28°" : ~ ' ' 



Other experiments gave 1.0015 and 1.0060, the mean of all of 

 which is 1.0033. Regnault's formula gives 1.005; but going directly 

 to his experiments, we get about 1.004, the other quantity being for 

 110°. 



The agreement is very satisfactory, though one would expect my 

 small apparatus to lose more of the heat of the boiling water than 

 Regnault's. Indeed, for high temperatures my apparatus is much 

 inferior to Regnault's, and so I have not attempted any further 

 experiments at high temperatures. 



