466 PROFESSOR A. SCHUSTER AND MR. W. GANNON ON A 
The calibration of the balance immediately after the experiment showed that 1 divi- 
sion = 0°00212 ampere, so that the mean value of the current flowing through the 
measuring coil in the final period was equal to 0°12987 ampere. From this and the 
data: resistance of coil = 31°32 B.A. units, 1 B.A. unit = ‘9866 x 10° C.G.S. unit, 
J. (assumed) = 4194 X 107, total water = 1540°50 grams. ; we easily obtain that the 
rise per minute due to auxiliary current = 0°°00484. As the observed rise per minute 
was 0°-00227, the cooling per minute in the final period was equal to 0°:00257. 
We require to know the temperature at 12 h. 11m. Since the cooling per minute 
at a mean temperature of the calorimeter of 17°°25 was — 0°:00406, and at a mean 
temperature of 19°76 was + 0°:00257, a slight calculation will show that the cooling 
per minute at 17°27 was equal to — 0°-00401, and at 19°°75 was + 0°'00254. 
We are now able to calculate the temperature rise. 

Temperature at 12 h. 12 m. 5 = LEO 
Rise in temperature during 55 seconds due to 
piallipia AMES SMS os a eon) a love "0044 
Coolinestors minutes sme a) ee ae 0025 
Therefore temperature at 12h, llm.. . . . = 19°7489 
Calibration correction at this pomt. . . . =— 0°0054 
Therefore corrected temperature at 12 be 11m. = OrAag 
ANeanoseauins ais WAIN I 5 gg a 5, ee IY 
Calibration correction at this pont. . . . = — 0°0050 
Therefore corrected temperature at 12 it ima: =p eZ OMe 
Difference of these temperatures. . . = RAoe 
To this difference we must add the following corrections :— 
(a) For the cooling during the time the main cir- 
cuit was closed, 10 x 3 (:00254—00401) = — 0°:00735 
(b) To correct for the wrong interval of the 
Baudin thermometer — 0°00135 xX 2°47 . = — 0°:00333 
(c)Ror thetemercent stem.) 3 3) 5 e c——OmOOlZG 
Ka) n(0) ta(C)is a raenns | ee ae ee =— 0°:0094 
Therefore corrected rise in temperature =  27-4669() 
J = wK/(001118 We) = 4°1807. 
