106 
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. 
superfusion had been avoided P) ; 0-1803 for sulphur which had been melted two months ; 
0*1764 for what had been melted two years (and which had then given 0-2026) ; 0-1796 
for sulphur of natural occurrence. The difference between the latter result and my 
own doubtless depends, partially at least, on the fact that Regnault’s determination was 
made between 14° and 99° (the latter of which temperatures is very near the melting- 
point of rhombic sulphur) ; mine was made between 17° and 45° *. 
Tellurium : crystalline pieces f . 
Experiments with Naphtha A. 
Glass 3. Temperature of the Air 18 
°*6-19°v 
T. 
T'. t'. t. 
M. m. 
/• y- 
■ X. 
sp. H. 
o 
o o o 
grms. grms. 
grm. 
grm. 
51-8 
20-4 20-07 17-96 
26-93 10-80 
1-93 0-431 
0-453 
0-0486 
51-3 
20-3 20-02 17-93 
26-98 
35 33 
33 
0-0495 
51-5 
20-7 20-36 18-33 
26-93 
33 33 
„ 
0-0454 
51-0 
20-7 20-43 18-43 
26-955 „ 
1-91$ 
33 
0-0466 
Mean 
0-0475 
34. Boron . — I have made some experiments with this substance, which have some 
interest for the question whether this body has essentially different specific heats in its 
different modifications ; but the results are not very trustworthy, owing to the spongy 
nature of the amorphous boron and the doubtful purity of the crystallized variety. 
The amorphous Boron § which I investigated was pressed in small bars, and had stood 
several days in vacuo over sulphuric acid. 
Experiments with Naphtha A. Glass 1. Temperature of the Air 17 o "0-17 o- 2. 
T. 
o 
T'. 
o 
o 
t. 
o 
M. 
grms. 
m. 
grm. 
/• 
grms. 
y- 
X . 
grm. 
sp. H. 
49-0 
18-7 
18-73 
16-36 
26-955 
1-52 
2-515 
0-431 
0-651 
0-246 
48-1 
18-6 
18-55 
16-23 
26-965 
99 
99 
99 
99 
0-254 
48-0 
18-6 
18-64 
16-33 
26-95 
99 
99 
99 
99 
0-252 
47-9 
18-7 
18-72 
16-42 
26-95 
99 
2*49 J 
99 
Mean 
99 
0-262 
0-254 
Even if the results of the individual experiments agree tolerably with each other they 
are not very trustworthy ; for the quantity of boron (only 1^ grm.) is very small, and 
the amount of heat due to the boron is a very small part of the total (comp. § 19). 
Yet I do not consider the result of the above series of experiments (that between 18° 
and 48° the specific heat of amorphous boron is about 0-254) as being very far from 
* There is nothing known certainly as to whether the different modifications of sulphur have essentially 
different specific heats. Marchand and Scheerer’s experiments on brown and yellow sulphur made by the 
method of cooling, compare in Journal fiir Prakt. Chemie, vol. xxiv. p. 153. 
f “ Obtained from Yienna, and obviously distilled.” — Wohler. 
+ After drying the stopper. 
§ “ Prepared from boracic acid by sodium, and treated with hydrochloric acid.” — Wohler. 
