CONDUCTIVITIES OF IRON AND COPPER. 
581 
I. 
Table showing the Data for Determination of Bore of Tube. 
Temperatcire. 
Weight of mercury. 
Length of thread. 
[Corrected by cali¬ 
bration curve.] 
Volume of 1 centim. 
of bore. 
°C. 
grms. 
centims. 
13 
0-9092 
99-80 
-000672 
13 
0-8700 
9.5-15 
•000674 
"000673 (mean) 
Table giving Data for Specific Heat Determinations. 
Mass of iron. 
Temperature of 
iron (^). 
Deflection of 
mei’cury thread. 
Heat required to raise 
unit mass of iron 
from 0° C. to t° C. 
Und 
grms. 
° C. 
centims. 
2-1025 
41 
16-0 
4-5172 
2-1025 
55 
21-7 
61264 
2-1025 
98 
.39-3 
11-0950 
2-10-25 
102 
40-6 
11-4360 
1-3440 
150 
39-7 
17-5340 
1-3440 
170 
44 -/ 
19-7420 
Assuming 
]i( — Lit -h 
and reducing by method of least squares, we have 
and, therefore. 
or 
lit — -1095^ + •000040D-^ 
dhtidt = Si = a 2bt — T095 + -OOOOSq 
-1095 (1 + -00073^) 
where St denotes tlie true specific heat at f C. 
Determination of Density of Iron, and. the Value of (sd) the Thermal Capacity oj 
Unit Volume. 
The density of the iron was found bo be 7’556 at 0° C. For present purposes this 
may be taken as 7’56, and the density at f C. will be given ty 
7-56 (1 - -0000380. 
