330 Dove on the Law of Storms. 



as the air flows with redoubled velocity between two mountains. 

 The reason of the course of the storm being in the first instance 

 from S. E. to N. W M may be explained by the circumstance, that 

 according to the theoretical deduction which has been given, this 

 direction is the one most favorable to the origination of a rotatory 

 movement. If, as may happen, the first impulse should be from 

 S. W. to N. E., the northeast trade blowing in the opposite direc- 

 tion would equally check all the points of the advancing line, so 

 that no tendency to rotate would be produced. f 



It is evident that if the above deduction of these phenomena 

 be the true one, a similar whirlwind must be produced whenever, 

 owing to any other mechanical cause, a current flowing towards 

 higher northern latitudes is more southerly on its eastern side 

 than on its western, where the direction is more towards the east. 

 Observations collected by Piddington,* show this to have been 

 the case in the storm in the bay of Bengal on the 3rd, 4th and 

 5th of June, 1838. It was one of those storms which usually 

 accompany the change of the northeast to the southwest mon- 

 soon, which change takes place in the bay of Bengal between 

 the 15th of May and the 15th of June.f Throughout the great- 

 er part of its course, "it was a gale or strong wind blowing with 

 tolerable steadiness from one quarter of the compass," and it was 

 only at a particular part that it was a hurricane or violent wind 

 blowing in a circle or vortex of greater or less diameter.^ It 

 blew as a violent southwest monsoon in the space between the 

 east coast of Ceylon and Masulipatam, and across the bay of Ben- 



* Researches on the Gale and Hurricane in the Bay of Bengal on the 3rd, 4th 

 and 5th of June, 1838, being a first Memoir with reference to the Theory of 

 Storms in India. Journal of the Asiatic Society of Bengal, No. 91, p. 550; Sec- 

 ond Part, No. 52, p. 631. &f6 



\ According to the observations of Brown, it commenced at Anjarakandy on 

 the Malabar coast in 1820-1833, on May 20, 31, 27, June 15, May 21, June 18, 

 May 26, June 5, May 9, 26, June 16, 2, 6 ; at Canton it set in, according to the 

 Canton Register, from the 20th to 28th of April in 1830, from the 7th to 17th of 

 April in 1831, from the 4th to 7th of April in 1832, from the 9th to 14th of April 

 in 1833, from the 3rd of April to 8th of May in 1834, and from the 8th to the 21st 

 of April in 1835. 



X This seems to be also the case with the storms which accompany the change 

 from the southwest to the northeast monsoon. These storms, which the Spaniards 

 in Manilla call " los temporales," are not accompanied by rain, but the air is every 

 where darkened by the salt spray from the sea. On the coast of Coromandel 

 these storms are termed " the breaking out of the monsoon." On the Malabar 

 coast the Portuguese call those which are peculiarly violent, " Elephanta." 



