582 
DE. J. P. JOULE AKD PEOPESSOE W. THOMSON OX 
Oxygen Gas. 
This elastic fluid was procured by cautiously heating chlorate of potash mixed with a 
small quantity of peroxide of manganese. In its way to the meter it passed through a 
tube containing caustic potash, in order to deprive it of any carbonic acid it might con- 
tain. The same drying-apparatus was employed as in the case of atmospheric air. 
Table II. 
Nitrogen Gets. 
In preparing this gas the meter was first filled with air, and then a long shallow tin 
vessel was floated under it, containing sticks of phosphorus so disposed as to burn in 
succession. Some hours were allowed to elapse after the combustion had terminated, 
in order to allow of the deposition of the phosphoric acid formed. 
Table III. 
Wo. of exporiment. 
Cubical inches 
of elastic iluid trans- 
mitted per minute. 
Composition of tho 
elastic fluid. 
Pressure over that of 
tho atmosphere, 
in inches of mercury. 
Temperature of the 
bath. 
Thermal effect. 
Correction on 
account of conduc- 
tion of heat. 
Corrected thermal 
effect. 
‘ Thermal effect 
reduced to the 
pressure of 100 
inches of mercury. 
Ditto, 
calculated for 
pure nitrogen. 
Time occupied 
by experiment, 
in minutes. 
Number of observa- 
tions comprised in 
each mean. 
Extreme range 
of the temperature 
of the bath. 
Extreme range 
of the temperature 
of tho elastic fluid. 
Extreme range 
of tho pressure. 
1 
2050 
1 
r 7-9 01 
L92-1 N 
>■ 
163-38 
7-204 
-i-448 
-0-133 
-f-581 
-0°967 
-l°-034 
7 
8 
0-008 
0-25 
6-2 
2 
2500 
J 
r 2-2 01 
97-8 N 
>■ 
162-65 
91-415 
-0-857 
-0-064 
-0-921 
-0-567 
-0-576 
13 
10 
0-036 
0-48 
4-5 
3 
2500 
-! 
r 12-5 0 
[_ 87-5 W j 
164-61 
91-965 
-0-869 
-0-065 
-0-934 
-0-567 
-0-691 
12 
9 
0-337 
0-378 
30 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
Carbonic Acid. 
This gas was formed by adding sulphuric acid to a solution of carbonate of soda. It 
was dried in the same manner as all the other gases. 
