5T2 ON A NEW METHOD FOR ASCERTAINING 
properly furnished with stirrers and thermome- 
ters of known capacity. A current from a 
battery of six large Daniell’s cells was then 
passed through the platinum wires for 20 minutes ; 
at the end of which time the increase of the 
temperature of the standard vessel was 3°°575, 
and of the experimental vessel 4°35. Applying 
equation 6, and turning all the weights into 
grains,* I had 
9280 x 3°575 x 106 —28260 x 4°35 x 100 _ 9.93973 
80500% 4°35 x 100 
Another experiment was conducted in the 
same manner; but in this instance the ther- 
mometers and platinum conducting wires were 
made to change places in the vessels, so as to 
detect any small error in the values of the scales 
of the thermometers, or in the resistances of 
the wires. The result of this second experiment 
was 0°0299. The mean of the two results is 
0:0303. The result of Dulong and Petit is 
0:0293 ; that of Regnault 0°0314. 
I made two experiments also on the specific 
heat of wrought iron. The mean result of them 
* The capacities of the vessels, thermometers, &c., were 
found to be equivalent to those of 280 and 260 grs. of water. 
Hence in the equation a=35000 +280, and a'=28000-+260. 
