THE MECHANICAL EQUIVALENT OF HEAT. 
491 
Wi = 139776 
Tj,o = 458-87 
Ti,3 = 459-81 
Wa = 259-500 
T2 ,o= 702-91 
To,3 = 703-20 
= 15° C. 
= 25° a 
E = 1-4344* volts. 
Substituting these values in equation (15) and dividing, we obtain 
1 + 15/ _ 243-39 
1 + 25/ ~ 244-04 
•99734. 
As the difference in weight of water here amounts to nearly 120 grins., it is 
probable that the value obtained in this case is the most reliable. 
In the same manner using the values of W and T given in Columns 4 and 5, 
we get 
1 + 15/ _ 121-74 
l'+ 25/“ 122-08 
-99722. 
And again from Columns 5 and 6, 
1 + 15/ _ 121-05 
1 + 25/” 121-96 
-99746. 
Hence mean value of ^ deduced from Series II. = -99734.t 
1 + 25/ 
Hence, adopting 15° C. as the standard temperature, the 
Specific Heat ofWater = 1 — *000266 {0^ — 15).| 
Also by means of equation (15) we get the following values of J, 
Columns 4 and 6 . . . . J = 4-1939 X 10'^ 
„ 4 „ 5 . . . . J = 4-1940 X 10^ 
„ 5 „ 6 . . . . J = 4-1940 X 10^ 
Mean .... 4*1940 X 10/ 
This value of J, as pointed out on p. 481, is entirely inde]jendent of the value 
assigned to the voater equivalent of the calorimeter. 
Performing the operations of equation 16 , we find that the water equivalent at 
* See p. 388, supra. 
t If we mean tlie results from Columns 4 and 5 and 5 and 6, we must of course obtain the same result 
as that given by Columns 4 and 6. We have however given the numbers in the above form as they 
show the nature of the agreement between the different groups. 
+ Over the range 14° to 26° C. 
3 R 2 
