182 H. F. Blanford— On the Climate of Bengal. [Nov. 



Calcutta the highest rainfall on record is that of 1871, when it amounted 

 to 9331 inches; the lowest during the last forty-five years is that in 1837, 

 when the registered fall was as low as 4361 inches. In subsequent years the 

 lowest falls were those of 1S38 (53 - ? inches), 1853 (52"08 inches) and 

 1860 (5261 inches) ; up to the present year 1873, which now, (in November.) 

 exceeds that of 1837 by about one inch only. The Cherra Punji register 

 of 1861 records a fall of 805" inches, of which 3l>6" inches fell in the 

 month of July alone ; hut it is not clear that this register is deserving 

 of complete reliance. Twelve inches of rain in one day is however, far from 

 unusual at Cherra Punji. On the 13th June, 1861, an equal quantity fell in 

 Calcutta within 21 hours, and on the 11th May 1835 the same quantity fill 

 within three hours. 



By far the greater part of the rainfall of Bengal falls between the months 

 of June and October. Showers occur also in the hot weather months, and 

 in the months of February and March hail-storms are not infrequent. In 

 the Eastern districts, rain occurs occasionally in the cold weather months, 

 but is less common in the Delta and the country further Westward, except- 

 ing in the N. W. Provinces and the Panjab. In the Eastern districts and 

 in Asam, rain is more abundant in all the earlier months of the year, and 

 in April it sets in heavily, and reaches its maximum about June or July. 

 Further to the West, the rains usually set in in June, and July and August 

 are the months of the heaviest fall. 



Except at the hill stations and in the immediate neighbourhood of the 

 hills, the average proportion of cloud-covered sky varies between one-third 

 and one-half of the whole. At Darjiling, on an average, the proportion of 

 clouded sky to sunny sky is as 2 to 1. In Lower Bengal generally it is 

 about 1 to 2 ; being however, rather higher on the coast. December and 

 January are on the whole the brightest months of the year ; but November, 

 February and March are almost equally serene. June, July and August are 

 the months of greatest obscurity. In these former months, the proportion 

 of cloud is on an average from 10 to 15 per cent., in the latter months from 

 65 to 85 per cent. 



These observations refer to visible dense cloud, but the depth of the 

 sky tint indicating the pressure or absence of diffused cloud in the upper 

 regions of the atmosphere would appear to follow a different law. No sys- 

 tematic observation has been made on the colour of the sky, but as the results 

 of my own casual observations I gather that the sky tint is, on an average, 

 much paler in the cold weather, than during fine intervals of the rains, 

 indicating a greater quantity of condensed moisture at great altitudes. 



The wind system of Bengal is so often referred to as a familiar illustra- 

 tion of the monsoons, that it might seem almost superfluous to re-describe 

 a subject treated of in every text book on Meteorology. But it appears 



