592 
ME. H. F. BLANFOED ON THE WINDS OF NOETHEEN INDIA. 
It will be observed that in the case of the damp climate of the Sikkim Himalaya 
the temperature-difference curve is considerably less irregular than in the dry climate 
of the North-western Provinces, and that the absolute minimum difference at Darjee- 
ling and the secondary minimum at Chuckrata coincide with the high humidity of the 
rains. Further, that the rise of temperature over the plains in the early months of the 
year is felt at Darjeeling two months earlier than at Chuckrata ; and the rise of tem- 
perature at the former between March and June, which much exceeds that at the lower 
station of Goalpara (reducing their difference), and which I suppose to be due to the 
condensation of moisture as cloud and rain in those months, is but faintly indicated, 
and at a later season at Chuckrata, where the rainfall is small at that period of the year. 
(See the Rainfall Table at the end*.) One very important datum is yet wanting for 
the north-western hill-stations, viz. the proportion of cloud-obscuration ; and the radia- 
tion observations are imperfect. At Roorkee the sky is more free from cloud in October 
than in any other month of the year, and the same is probably the case at Chuckrata. 
If so, the great difference of temperature in this month may be due to the increased 
radiation at the upper station. It is to be hoped that in the course of a few years data 
will be collected that will admit of a more satisfactory investigation of the subject f. 
* The rainfall Tables for Nynee Tal and Simla may be taken as illustrations of the rainfall of the North-west 
Himalaya in lieu of that of Chuckrata, of which I have the record for only two years. 
f The registers of the temperature of nocturnal radiation at the hill- stations of the North-western Provinces 
are at present imperfect, and there appears to he a peculiar difficulty in obtaining observations at such stations 
that shall he comparable with those on plains’ stations, owing to the convection of the cooled air on sloping 
ground. It may be therefore, and probably is the case, that the recorded temperatures of radiation at night 
are much above those that would be given by an instrument placed in a hollow. I find in Dr. Thomson’s 
Eeports one year’s observations at Nynee Tal, 10 months’ at Eaneekhet near Nynee Tal, and 7 months’ at 
Chuckrata. The following Table gives in one column the means of all these (without distinction of station), in 
another those of the same years at Eoorkee, and in a third the difference of the two. The remaining columns 
show the mean maximum temperatures of solar radiation for the same years treated in like manner, and their 
differences. 
Grass Nocturnal Radiation. 
Solar Radiation. 
Hill- 
stations. 
Roorkee. 
Difference, 
R.-H. 
Hill- 
stations. 
Roorkee. 
Difference, 
R.-H. 
January 
27-3 
40 
12-7 
85-2 
110 
24-8 
February 
28-6 
41-5 
12-9 
90-3 
114-5 
24-2 
March 
38-5 
51-5 
13 
113 
128 
15 
April 
43-6 
60 
16-4 
119-3 
129 
9-7 
May 
50-3 
67 
16-7 
121-7 
143-5 
21-8 
June 
53 
74-5 
21-5 
121-3 
139-5 
18-2 
July 
52-5 
76 
13-5 
114-7 
133 
18-3 
August 
54 
75 
21 
115-3 
127 
11-7 
September 
51 
72 
21 
123-4 
127-9 
4-5 
October 
38-8 
56-8 
16 
123-3 
127-8 
4-5 
November 
34-5 
43-1 
18-6 
114-5 
121-1 
6-6 
December 
28-9 
38 
9-1 
97-5 
109-7 
21-2 
From this rough comparison it would seem that the excess of nocturnal radiation at the hill-stations in 
October is not so great as in the rainy months ; and so far the fall of temperature in that and the preceding 
