70 J. Eliot— T7ie SoiUh-West Monsoon Storms [No. 2, 



of this advancing strong moisture current, where the resistance to its 

 advance was greatest, and where therefore ascensional motion was neces- 

 sarily occurring to a large extent, rainfall of a more or less concentrated 

 character was going on. The current was being deflected to the west 

 by the coast and the Burmese and Arracan hills, and was moving more 

 rapidly in its eastern than in its western portion. Hence probably also 

 arose a strong tendency to an eddying motion in front and towards the west. 

 The various actions going on were thus such as might set up vorticose 

 motion. That such a result was taking place was indicated by the wind 

 observations of all the vessels near the Head of the Bay. The Himalaya, 

 in Lat. 17° 32' N. and Long. 84° 75' E., had moderate westerly winds. The 

 India, British Princess, Star of Albion, Scottish Chieftain, Saint Mag- 

 nus, Boma, and Prince Amadeo, which were all between Lat. 19° 20' N. 

 and 20° 19' 'N. and between Long. 86° 20' E. and 87° 18' East, experienced 

 light unsteady north-easterly winds. The weather was fine and sky clear 

 during the greater part of the day, but became more clouded during the 

 evening. There was a heavy swell from the south during the day. This 

 was evidently due to the strong winds and high sea prevalent in the 

 centre and south-east of the Bay. The only log which gives any in- 

 dication of the subsequent weather is that of the Prince Amadeo, in 

 which the Captain notes that, although light variable airs were blowing, 

 the appearance of the sky was unsettled in all directions. Probably the 

 light green sky to the east noted by the Captain of the British Princess 

 was another sign of the large amount of moisture brought up by the 

 southerly winds in the East of the Bay. 



The various observations of the 26th hence indicate that cyclonic 

 motion on a considerable scale commenced on the afternoon of the 25th 

 over a portion of the Head of the Bay. The atmospheric whirl was fed and 

 maintained by a very strong south-westerly air current moving north- 

 wards up the Bay near the Burmah and Arracan coast. It was appa- 

 rently formed in the front of this air-current, and was causing winds 

 to draw round over the north-west of the Bay. The indraught from 

 that quarter was, however, feeble and unimportant, except as an indicator 

 of bad weather to the south-east. 



27th June. — The decrease of pressure which commenced on the 26th 

 had now extended over the whole country. The change was still greatest 

 in the north. On the northern frontier of the Punjab, in Eastern and Lower 

 Bengal, and at Akyab the decrease exceeded one-tenth of an inch. It was 

 smallest in parts of Bombay and Madras, where it only amounted to two 

 or three-hundreths of an inch. A considerable depression lay over the 

 Punjab. This, however, is a frequent feature of the hot weather months 

 of June and July in that province. A smaller depression was, however, 



I 



