1870.] Irregularities of Atmospheric pressure in Bengal, Sfc. 131 



until the end of September that the contraction of this depression 

 allowed the N. W. Provinces to receive their usual rainfall, as it 

 would appear, by leaving the winds from the Bay to follow their 

 normal course across Hazaribaugh and Chota-Nagpoor towards 

 the Upper Provinces. 



In June the heaviest rainfall occurred at Julpigori (41-29 ins.) 

 and Eungpore (36-7 ins). At the stations of Dinagepore, Pubna, 

 Malda, Buxa, (Bhotan Doars,) and Groulpara more than 20 

 inches were registered, while at Darjiling at which the average 

 rainfall for this month is 27*50* ins., 19.85 inches only fell. At 

 Calcutta the rainfall for the month amounted to 18*84 inches ; but 

 of this, 1 1 inches fell in one day, during the Cyclone of the 9th 

 June, the centre of which passed very near Calcutta. Berhampore 

 received 21*74 inches of which 5*7 fell during the passage of the 

 Cyclone and Eampore Beauleah, which was also near its track, 

 18*05 inches, in all of which 6 inches fell on the day of the storm. 

 It would appear then that the heaviest fall was to North East of 

 the depression, the maximum being at 150 miles from the seat of 

 greatest depression much as in August of the previous year. In 

 the present case, however, the place of maximum rainfall was pro- 

 bably determined by the proximity of the hills. 



That the winds in May and June were greatly influenced by the 

 local barometric depression, and instead of blowing up the Ganges 

 valley, drew in towards the depression with a tendency to circulate 

 round it, is shewn by the following table, which exhibits also the 

 increase of Easterly components in September when the rains 

 reached the Upper Provinces. 



It may be noticed, however, that as in the previous year, the in- 

 fluence of the local depression was sufficient only to modify and 

 weaken, not to counteract that of the probably more extensive area 

 of low pressure, which many circumstances lead me to believe must 

 exist in Central India, as a normal phenomenon of the S. W. 

 monsoon. 



May. June. July. Aug. Sept. 



Cuttack, .... 79S 6°E 58S 3°E 58S 49°W 55S 19°W 30S 17°E 

 False Point, . . 63S 15°W 53S 25°E 72S 67°W 63S 56°W 41S 39°W 

 * Mean of 7 years. 



