131 
TABLE 1. 
Radiation Thermometers. — Mean Monthly Maximum 
in the Sun. 
January. 
In 
Vacuo. 
In 
Carbonic 
Acid 
Gas. 
In 
Hydrogen 
Gas. 
Con- 
densed 
Air. 
Black 
Bulb 
Freely 
Exposed. 
Maxi- 
mum 
in 
Shade. 
o 
o 
o 
o 
o 
o 
18G2 
1863 
48-0 
46 3 
46-4 
47 8 
41-6 
43-2 
1864 
45T 
45-0 
44-7 
45-4 
43-4 
41-9 
1865 
44-3 
44-1 
44-1 
44-2 
43-6 
41-3 
Means 
45-8 
45-1 
45-1 
45-8 
43-8 
42-1 
February. 
In 
Vacuo. 
In 
Carbonic 
Acid 
Gas. 
in 
Hydrogen 
Gas. 
Con- 
densed 
Air. 
Black 
Bulb 
Freely 
Exposed. 
Maxi- 
mum 
in 
Shade. 
O 
° 
o 
o 
o 
o 
1862 
54-8 
53-2 
53-0 
54-2 
49-7 
46-3 
1863 
654) 
61-9 
62-4 
62-1 
55-2 
50-0 
1864 
50-5 
49-3 
48-9 
53-6 
45-5 
42-0 
1865 
50-7 
51-3 
51 T 
50-8 
46-8 
42-3 
Means 
55-2 
53-9 
53-8 
55-2 
49 -3 
45T 
March. 
in 
Vacuo. 
iu 
Carbonic 
Acid 
Gas. 
In 
Hydrogen 
Gas. 
Con- 
densed 
Air. 
Black 
Bulb 
Freely 
Exposed. 
Maxi- 
mum 
in 
Shade. 
o 
o 
o 
o 
o 
o 
1862 
64-4 
61-3 
60-3 
60-7 
56-8 
48-9 
1863 
75-7 
73-6 
72-1 
72-1 
62-8 
52-6 
1864 
70-6 
69-6 
68-3 
69-1 
59-8 
48-9 
1865 
65-3 
64-9 
65-9 
63-1 
57-0 
44T 
Means 
690 
67-3 
66-6 
66-2 
59T 
48-6 
April. 
In 
Vacuo. 
In 
Carbonic 
Acid 
Gas. 
In 
Hydrogen- 
Gas. 
Con- 
densed 
Air. 
Black 
Bulb 
Freely 
Exposed. 
Maxi- 
mum 
in 
Shade. 
o 
o 
o 
o 
o 
o 
1862 
81-6 
76-1 
73-6 
75-3 
70-8 
57-5 
1863 
86-0 
83-3 
81-2 
81-8 
69-9 
56-2 
1864 
85-8 
83-4 
81-9 
82-8 
76-0 
60-0 
1865 
92 6 
91-3 
89-4 
89-3 
81-5 
63-5 
Means 
86-5 
83-5 
81-5 
82-3 
74-6 
59-3 
