MR, H. F. BLANFORD ON THE WINDS OF NORTHERN INDIA. 
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2000 feet lower, and the Naga hills still less elevated, with the exception of the 
Burrail range, on the south-east and south, which rises to about 5000 feet. Between 
the western extremity of this range and the Khasi hills is left a comparatively free 
passage, at a lower level, for the monsoon winds blowing to or from the upper part of 
Assam. On the north the Bhotan Himalaya runs parallel with the valley up to the 
gorge by which the great Dihong river breaks through the mountains, and affords an 
open passage to the monsoons to penetrate to the region north of the Himalaya. 
Seebsaugor lies to the south and a little to the west of this break in the mountain- 
chain, full in the course of the alternating currents, but sheltered somewhat by its 
depressed position on the alluvial plain between the two hill-ranges. Goalpara, on the 
other hand, is situated at the lower end of the valley, due north of the Garo hills, and 
completely shielded on the north by the Bhotan Himalaya. 
The Tables for both these stations are drawn up from the observations of three years 
(recorded four times daily). The Seebsaugor observations are evidently somewhat rough ; 
but there seems no reason to doubt their general trustworthiness, except in so far as they 
may be vitiated by the usual omission of calms. Both Tables show a preponderance of 
easterly winds, as decided as is that of westerly winds in the peninsula of India. At 
Goalpara this excess of easterly winds holds good in every month of the year, and the 
only change in the mean direction of the wind is an oscillation through about 7 points 
of the compass, from east by north in March to south-south-east in July, and back again 
during the remainder of the year. North-east winds are most frequent in the winter 
months, and attain their maximum in March. West winds are also at their maximum 
in the same months, in which respect Goalpara resembles Berhampore. In May east 
winds attain their annual maximum, amounting to 59 per cent, of the observations ; but 
in the following months, during the prevalence of the south-west monsoon, winds from 
south, south-west, and west are frequent. In respect of mean velocity, there are two 
epochs of maximum and two of minimum annually. The former occur in April and 
September, the latter in July and December; of these, the April maximum is the abso- 
lute maximum of the year, and the December minimum is generally below that of July. 
At Seebsaugor, winds from the north and north-east amount together to 54 per cent, 
on the average of the year, while those from south and south-west do not exceed 29 per 
cent. The air-current from the direction of the great Dihong valley (possibly derived 
from Tibet) preponderates considerably over that from the sea. Nevertheless the 
climate of Seebsaugor, though cool, is not so dry as this fact might lead us to antici- 
pate ; the rainfall is not much less than at Goalpara, and occurs at all seasons of the 
year : this fact leads me to doubt whether in reality any considerable body of air is 
drawn from the trans-TIimalayan region. The winter monsoon from north and north- 
east sets in in October and blows with great steadiness through November and Decem- 
ber. In January westerly winds begin to be felt, and gradually increase during the 
following months, chiefly from south-west, until in June they predominate over those 
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