126 
PKOFESSOB KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. 
Oxide of Chromium , Cr 2 0 3 . Crystalline crusts prepared from oxychloride of chromium. 
Experiments with Naphtha A. Glass 3. Temperature of the Air 19°T. 
T. 
T'. 
t'. 
t. 
M. 
m. 
/• 
y- 
X. 
sp. H. 
52-1 
21-5 
21*23 
18*53 
grms. 
26*955 
grms. 
5*405 
grm. 
2*255 
0*431 
grm. 
0*453 
0*176 
51-5 
2T2 
20*93 
18*22 
26*955 
55 
55 
55 
0*181 
53-1 
21-4 
21*06 
18*25 
26*945 
55 
55 
55 
55 
0*178 
52-1 
21*2 
20*94 
18*23 
26*99 
55 
2*245 * 
55 
„ 
0*175 
Mean . . . 0T77 
Hydrated Sesguioxide of Manganese Mn 2 0 3 -|-H 2 Of. Fragments of good crystals 
of Manganite from Ihlefeld in the Harz, dried at 40° to 50°. 
Experiments with Naphtha A. Glass 3. Temperature of the Air 14°*6-14°*4. 
T. 
T'. 
t\ 
t. 
M. 
m. 
/• y- 
X . 
sp. H. 
c 
0 
o 
grms. 
grms. 
grm. 
grm. 
47*0 
17*1 
16*82 
13*83 
26*985 
8*31 
1*855 0*431 
0*453 
0*174 
45*6 
17*0 
16*69 
13*83 
26*94 
55 
55 55 
55 
0*173 
45*7 
17*0 
16*73 
13*85 
26*92 
” 
1*845* „ 
Mean 
55 
0*174 
0*174 
I made subsequently another series of experiments with a specimen from the same 
locality dried at the ordinary temperature. 
Experiments with Naphtha A. Glass 3. Temperature of the Air 17°*7— 1 7°*4. 
T. 
T'. 
t'. 
t. 
M. 
m. 
/• 
y- 
X. 
sp. H. 
o 
o 
0 
0 
grms. 
grms. 
grm. 
grm. 
52*0 
20*5 
20*15 
17*06 
26*95 
8*04 
1*77 
0*431 
0-453 
0*178 
52*3 
20*3 
2Q-02 
16*86 
26*975 
55 
55 
55 
55 
0*180 
51-9 
20*1 
19*77 
16*65 
26*965 
55 
55 
55 
55 
0*178 
51*6 
20*1 
19*84 
16*80 
26*995 
55 
1*75 
% 
55 
55 
0*174 
Mean 
0*178 
The specific heat of manganite between 19° and 49° is 0T76, the mean of the 
averages of both series of determinations. 
* After drying the stopper. 
t “ Manganite dried at about 80°-90°, and then kept for half a day over sulphuric acid, gave in a ■water- 
determination, in which the water was collected in a chloride of calcium tube, 9-96 per cent, of water.” — Knop. 
The above formula requires 10-23 per cent, of water. 
