204 
MR. GLAISHER ON THE RADIATION OF HEAT, 
Table CII. — Showing the excess of reading of the thermometer in Air, above those 
placed as stated in the 2nd column, in each of the years 1843 and 1844, and for 
both years together. 
General state 
of the sky 
during the 
night previous 
to reading the 
instruments. 
Situation of the thermometer. 
The mean yearly excess, according to the state of the sky, of the reading of a self- 
registering minimum thermometer placed in air at the height of 4feet, and protected 
from radiation, above that of a similar thermometer placed on different substances. 
1843. 
1844. 
1843 and 1844. 
Number 
of 
nights. 
Sum of 
excesses. 
Mean 
excess. 
Number 
of 
nights. 
Sum of 
excesses. 
Mean 
excess. 
Whole 
number 
of 
nights. 
Whole 
sum of 
excesses. 
Mean 
excess. 
Cloudy. 
On long grass exposed to |4hs of the sky 
29 
95-6 
o 
3-3 
o 
o 
29 
95-6 
o 
3-3 
On long grass fully exposed to the sky 
30 
85-9 
2-9 
99 
360-2 
3-7 
129 
446-1 
3-4 
On short grass fully exposed to the sky 
58 
159*5 
2-8 
98 
281-6 
2-9 
156 
441-1 
2-8 
On garden mould 
29 
40-2 
1-4 
29 
40-2 
1-4 
One inch above grass 
34 
103-0 
3-0 
34 
103-0 
3-0 
Three inches above grass 
31 
111-5 
3-6 
31 
111-5 
3-6 
Six inches above grass 
On white raw wool 
25 
70-6 
2-8 
40 
186-5 
4-7 
65 
257'1 
3-9 
On fine flax 
6 
15-7 
2-6 
92 
363-8 
4-0 
98 
379-5 
3-9 
On coarse flax 
22 
67-6 
3-1 
22 
67-6 
3-1 
On white unwrought cotton wool 
5 
11-2 
2-2 
5 
11-2 
2-2 
On lead 
11 
31-0 
2-8 
11 
31-0 
2-8 
On blackened tin 
15 
33-5 
2-2 
14 
62-7 
4-5 
29 
96-2 
3-3 
On white tin 
16 
38-4 
2-4 
14 
50-7 
3-6 
40 
89-1 
2-2 
In focus of metallic reflector 
86 
281-4 
3-3 
97 
322-9 
3-3 
183 
604-3 
3-3 
Principally 
On long grass exposed to fths of the sky 
25 
101-2 
4-1 
25 
101-2 
4-0 
cloudy. 
On long grass fully exposed to the sky 
13 
76-9 
5-9 
50 
354-7 
7*1 
63 
431-6 
6-8 
On short grass fully exposed 
39 
181-8 
4-6 
50 
303-3 
6-1 
89 
485-1 
5-5 
On garden mould fully exposed 
16 
59-7 
3-7 
16 
59-7 
3-7 
One inch above grass . 
28 
146-0 
5-2 
28 
146-0 
5-2 
Three inches above crass 
29 
149-0 
5-1 
29 
149-0 
5-2 
Six inches above crass 
On white raw wool 
10 
53-9 
5-4 
37 
302-0 
8-2 
47 
355-9 
7-5 
On fine flax 
3 
11-1 
3-7 
46 
352-9 
7-7 
49 
364-0 
7-4 
On coarse flax 
8 
45-4 
5-7 
8 
45-4 
5-7 
On white unwrought cotton wool 
1 
6-5 
6-5 
1 
6*5 
6*5 
On lead 
44-3 
6-3 
7 
44-3 
6-3 
On blackened tin 
7 
36-1 
5-1 
13 
75-8 
5-8 
20 
111-9 
5*6 
On white tin 
6 
24-2 
4-0 
13 
71-7 
5-3 
19 
95-9 
5-0 
In focus of metallic reflector 
49 
258-2 
5-3 
49 
237*4 
4-9 
98 
495-6 
5-1 
Half- 
On long grass exposed to fths of the sky 
22 
88-6 
4-0 
22 
88-6 
4-0 
cloudy. 
On long grass fully exposed 
19 
120-7 
6-4 
58 
438-4 
7*6 
77 
559-1 
7-3 
On short grass 
42 
267-3 
6-4 
57 
353-6 
6-2 
99 
620-9 
6*5 
On garden mould 
10 
39-7 
4-0 
10 
39-7 
3-9 
One inch above grass 
34 
202-5 
5-9 
34 
202*5 
5-9 
Three inches above grass 
28 
168-9 
6-0 
28 
168-9 
6*0 
Six inches above crass 
3 
12-5 
4-2 
3 
12-5 
4-2 
On white raw wool 
9 
56-6 
6-3 
33 
250-7 
7-6 
42 
307-3 
7*3 
On fine flax 
11 
41-2 
3-7 
49 
383-9 
7-8 
60 
425*1 
7-1 
On coarse flax 
4 
25-5 
6-4 
4 
25-5 
6-4 
On white unwrought cotton wool 
4 
17-6 
4-4 
4 
17-6 
4-4 
On lead 
14 
70-7 
5-1 
14 
70-7 
5-1 
On blackened tin 
1 
5-9 
5-9 
11 
64-5 
5-9 
12 
70-4 
5-9 
On white tin 
1 
5-9 
5-9 
11 
53-9 
4-9 
12 
59-8 
5-0 
In focus of metallic reflector 
62 
394-9 
6*4 
60 
336-4 
5-6 
122 
731-3 
6-0 
