SUPPLEMENT TO THE HONGKONG GOVT GAZETTE OF 5TH MAR., 1887. 225
TABLE XVIII.
Average Readings of Solar Radiation Thermometers and Excess over Maximum Thermometers as well as Excess of Minimum over Terrestrial Radiation Thermometers, Mean Weight of Aqueous Vapour in Troy Grains
in each cubic foot of air and Diurnal Range of Temperature at the Observatory and at the Peak,
and average height in feet at which the Temperature of the air was 1o lower during 1886.
Solar Radiation Thermometer.
Solar Radiation. Excess over Maximum.
Terrestrial Radia- tion.
Weight of Aque- ous Vapour.
Diurnal Range.
Month.
Height of 1° Decrease.
Observa- tory.
Peak.
Observa- tory.
Peak.
Observa-
tory.
Peak.
Observa-
tory.
Peak.
Observa- tory.
Peak.
1886.
January, ... 112.0
107.6
49.9
52.0
+3.3 +3.4
3.74
3.92
6.6
5.3
299
February,
98.3
97.2
41.9
46.0
+0.9
+1.9
3.53
3.51
5.6
7.0
294
March,
117.2
113.7
51.5
30.6
+0.9 +1.7
5.41
5.41
6.6
8.1
656
April,
121.8
114.9
49.5
46.7
+1.3 +1.6
6.80
6.52
5.4
5.6
406
May,
137.8 127.2
58.2
54.4
+1.9 +2.1
7.85
7.39
6.7
5.2
294
June,..
138.6* 130.0
55.3
53.8
+2.8
+1.2
8.96
8.29
6.4
5.8
258
July,.
138.1
131.6
53.9
54.8
+2.7
+1.1
9.19
8.60
6.8
4.5
267
'August,
145.4
136.2
59.9
58.4
+1.6
+1.8
9.26
8.72
7.6
4.9
280
September,
143.9 140.0
59.6
62.7
+4.1
+3.9
7.30
7.18
8.1
6.8
280
October,
November,
December,
138.5
131.6
58.3
56.9
+3.0 +2.7
7.19
6.95
6.3
7.2
280
132.5 124.5
59.5
57.9
+4.4
+2.6
4.60
4.53
7.6
9.3
234
117.1 114.1
52.9
56.7
+5.5
+0.2
3.16
3.18
8.5
12.1
222
Mean,
128.4
122.4
54.2
54.2
+2.7
+2.0
6.42
6.18
6.8
6.8
314
Hongkong Observatory, 7th February, 1887..
W. DOBERCK,
Government Astronomer.