PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. 
161 
and to leave it undecided when, and in how many cases, other such exceptions might 
occur. 
Although the great distance of the temperatures used in my experiments from the 
melting-point of sesquichloride of carbon made it improbable, it was yet possible that 
the specific heat of this body varies considerably at the temperatures which I used, and 
is only constant and normal at still lower temperatures. In the preceding experiments I 
had heated sesquichloride of carbon to 49°-52° ; it was improbable that this body, at so 
great a distance from its melting-point (160°), should absorb latent heat in softening 
in appreciable quantity, yet the circumstance that this substance is brittle in the 
cold, but distinctly tougher at 50°, led me to determine the specific heat at lower tem- 
peratures than in the previous case. I made the two following series of experiments, a 
with sesquichloride crystallized from alcoholic, and b from ethereal solution : in both 
series the crystals dried at 100° were porcelain white in appearance. 
a.— Experiments with Water. Glass 1. Temperature of the Air 17 0, 8. 
T. 
T'. 
t'. 
t. 
M. 
m. 
/• 
y- 
X . 
sp. H, 
O 
o 
o 
Q 
grms. 
grms. 
grms. 
grm. 
36-8 
19-7 
19-35 
17-42 
26-98 
2-11 
2-085 
1-000 
0-651 
0-146 
37-6 
19-8 
19-52 
17 52 
26-94 
55 
„ 
55 
„ 
0-138 
37-2 
19-7 
19-44 
17-51 
26-94 
55 
55 
55 
55 
0-111 
37 T 
19*8 
19-45 
17-53 
26-98 
55 
2-075 
55 
0-127 
b.— 
Experiments with Water. Glass 3. 
Temperature of 
the Air 
17°-8. 
T. 
T'. 
t\ 
t. 
M. 
m. 
/• 
y- 
X . 
sp. H. 
o 
o 
0 
0 
grms. 
grms. 
grms. 
grm. 
37*2 
19-8 
19-45 
17-42 
26-98 
3-64 
2-11 
1-000 
0-453 
0-161 
37-2 
19*7 
19-43 
17-42 
26-99 
55 
55 
„ 
„ 
0-148 
37-3 
19-7 
19-44 
17-42 
26-965 
55 
55 
0-146 
37-3 
19-7 
19-44 
17-43 
26-965 
55 
2-10 
55 
55 
0-145 
h these series 
can only be considered 
as giving approximate : 
results. 
In both the 
magnitude T — T' is very small, not as much as 18°; in the series a the quantity of 
solid was moreover small, and its thermal action but a small fraction of the entire 
amount observed. The mean of the four experiments of the series b would give the 
specific heat between 20° and 37° at 0T5, and the first experiment of the series a agrees 
well with this. The specific heat here found between 20° and 37° comes very near that 
calculated from the composition, and is so much less than that found between 20° and 
50°, that it is probable this substance may towards 50° absorb heat in softening, the 
amount of which may make the numbers for the specific heat too great. 
To decide upon this point, T made two additional series of experiments in which, since 
the vessel containing sesquichloride of carbon and water could only be slightly heated 
* After drying the stopper. 
z 2 
