339 
» 
« " 
1830;] 
and the Communication of Heat. 
For the series in which the surrounding mass is at 60°, we shall have 
» = 3,222 (at— 1) 
Excess of temp, 
or values of t. 
Observed 
values of V. 
Calculated 
values of V. 
200° 
11°, 64 
1 . °,61 
180 
9 ,55 
9 ,52 
160 
7 ,68 
7 ,71 
140 
6 ,14 
6 ,16 
120 
4 ,84 
4 ,82 
100 
3 ,68 
3 ,69 
80 
2 ,73 
2 ,71 
60 
1 ,88 
1 ,87 
Finally, when the surrounding 1 matter is at 80°, we have 
v 3,754 (a 1 — 1) 
Excess of temp, 
or values of t. 
Observed 
values of V. 
Calculated 
values of V. 
200° 
13°, 45 
’ 13°, 52 
180 
11 ,05 
11 ,09 
160 
8 ,95 
8 ,98 
140 
7 ,19 
7 ,18 
120 
5 ,64 
5 ,61 
100 
4 ,29 
4 ,30 
80 
3 ,18 
3 ,16 
60 
2 ,17 
2,18 
The remarkable agreement of these results of observation and calculation will 
not allow of our doubting the truth of the law to whicli we have been led. Without 
stopping to trace all the consequences which may be deduced from it, let us proceed 
to examine the series made with the silvered bulb. When these series were calcu- 
lated, we did not fail to perceive, in comparing them with the analogous series of 
the naked thermometer, that the rates of cooling of this latter, for the same temper- 
ature of the surrounding matter, and for the same excess of temperature, were pro- 
portional to the corresponding rates of cooling of the thermometer with silvered bulb; 
the formula, then, will equally apply to this sort of surface, preserving for a the same 
value, and merely diminishing in. 
Our first observation on the cooling of the silvered thermometer was made when 
t was equal to 20°. We found that in this case m = 0,3.) 7, and consequently m « 
= 0,416, whence , , , 
’ V = 0,416 (at — 1) 
Excess of temp, 
or values of t. 
Observed 
values of V. 
Calculated 
values of V. 
3' 
Ml 
2 
,61 
2 
,18 
1 
,81 
1 
,50 
1 
,23 
1 
,00 
0 
,80 
0 
,62 
0 
,48 
0 
,35 
0 
,24 
0 
,15 
0 
,07 
