RADIATION OF HEAT BY GASEOUS AND LIQUID MATTER. 
205 
Table III. — Nitrous Oxide. 
Thickness of gas. 
Absorption in 
hundredths of the 
total radiation. 
Thickness of gas. 
Absorption in 
hundredths of the 
total radiation. 
0-01 of 
an inch 
. . . 1-48 
0-4 of 
an inch 
. . . 10-20 
0-02 
55 
. . . 2-33 
0-5 
55 
. . . 11-00 
0-03 
55 
. . . 3-80 
0-6 
5? 
. . . 11-70 
0-04 
55 
. . . 4-00 
0-8 
. . . 12-17 
0-05 
55 
. . . 4-20 
1-0 
55 
. . . 12-80 
0-1 
55 
. . . 6-00 
1-5 
55 
. . . 14-20 
0-2 
» 
. . . 7*77 
2-0 
. . . 15-7 
Table IV. — < 
Olefiant Gas. 
Thickness of gas. 
Absorption in 
hundredths of the 
total radiation. 
Thickness of gas. 
Absorption in 
hundredths of the 
total radiation. 
0-01 of an inch 
. . . 1-80 
0-5 of an inch 
. . . 23-30 
0-02 
55 
. . . 3-08 
10 
„ 
. . . 26-33 
0-05 
55 
. . . 5-37 
2-0 
95 
. . . 32-80 
0-1 
55 
. . . 9-14 
We here find that a layer of olefiant gas only 2 inches in thickness intercepts nearly 
33 per cent, of the radiation from our source. Supposing our globe to be encircled by 
a shell of olefiant gas only 2 inches in thickness, this shell would offer a scarcely 
sensible obstacle to the passage of the solar rays earthward, but it would cut off at least 
33 per cent, of the terrestrial radiation and in great part return it. Under such a canopy, 
trifling as it may appear, the surface of the earth would be kept at a stifling temperature. 
The possible influence of an atmospheric envelope on the temperature of a planet is 
here forcibly illustrated. 
The only vapour which I have examined with the piston apparatus is that of sulphuric 
ether. Glass fragments were placed in a U-tube and wetted with the ether. Through 
this tube dry air was gently forced, whence it passed, vapour-laden, into the space 
between the rock-salt plates S S'. The following Table contains the results. 
Table V. — Air saturated with the Vapour of Sulphuric Ether. 
Absorption in 
Thickness of vapour. hundredths of the 
total radiation. 
005 of an inch . . . 2-07 
0-1 „ ... 4-6 
0-2 „ ... 8-7 
0-4 „ ... 14-3 
Absorption in 
Thickness of vapour. hundredths of the 
total radiation. 
0- 8 of an inch . . . 21-0 
1- 5 „ ... 34*6 
20 „ ... 35-1 
