0 
the radiant heating effects from terrestrial sources, 195 
(14.) Flame of an Argand lamp without its chimney. 
Distance 3 inches. 
Glass screen 1.5 inch from bulbs. 
• 
a 
a> 
s 
• 
u 
Temperature of 
screen before expe- 
riment. 
Rise of Thermometers in 
I min. (centigrade.) 
Temperature of 
screen after ex- 
periment. 
CL, 
X 
W 
A. White. 
B. Black. 
1 
17 
1.25 
2.25 
< 
23. 
2 
1.25 
2.25 
3 
1-75 
2.25 
4 
1.25 
2.75 
5 
1. 
2.25 
Mean 
1.3 
2.35 
Effect of the screen alone 
heated above 25°. 
.25 
.25 
The former result diminished \ 
from this effect. j ' ^ 
2.10 
Lamp. No screen. 
1 
2.25 
3. 
2 
2.5 
3.25 
3 
2.25 
3. 
4 
2.25 
3.25 
5 
2.5 
3.5 
Mean 
2.35 
3.2 
Difference of the exposed 
and screened results. 
[ 1.3 
1.1 
