1879.] 
President's Address. 
59 
During the past year besides the Annual ‘ Reports on the Meteorology 
of India’ for 1876, by Mr. H. F. Blanford, a large quarto work on the 
Meteorology of the Bombay Presidency, accompanied by a portfolio of 
beautifully engraved maps and diagrams, has been published in London 
by Mr. Charles Chambers, F. R. S., Principal of the Bombay Observa¬ 
tory. In this work a summary of the results derived from the obser¬ 
vatory at Bombay since 1841, and especially from 1860, and for the 
last 17 years at Karachi, Disa, Puna and Belgaum, is supplemented by 
observations made at other stations. A second number of Indian Meteoro¬ 
logical Memoirs has also been piublished in Calcutta, containing papers “ on 
storms in Bengal with increased atmospheric pressure” by Mr. Eliot; “ on 
the rainfall of Benares” by Mr. Hill; and “ on the diurnal variation in the 
barometer at Calcutta and Hazaribagh” by Mr. H. F. Blanford. 
The investigation of cyclonic storms has always been one of the first 
duties of the Indian Meteorological Department, and has become doubly 
important now when so large a portion of the rainfall has been shewn to 
depend on the same laws as the destructive gales of the Bay of Bengal. 
Mr. Eliot’s masterly report on the Yizagapatam and Backergunge Cyclones 
of October 1876 was published in 1877, and was a most important addition 
to previous knowledge. The Backergunge Cyclone is probably the most 
destructive of which any accurate information has been recorded, for it 
caused the death of more than 100,000 human beings, but it furnished 
rather more data than usual for an examination of the meteorological 
phenomena which preceded and accompanied it. The result of the exami¬ 
nation of these two cyclones was distinctly in favor of Mr. II. F. Blanford’s 
local depression theory of the causes of cyclones. 
I now learn from Mr. Eliot, who has officiated as Meteorological 
Reporter for the greater part of the past year, that an investigation of 
some of the recent cyclones has not only apparently confirmed the views held 
by Mr. H. F. Blanford and himself as to the origin of cyclonic storms, but 
has also shewn that the paths of the intense cyclones of May and October 
follow the lines (approximately if not exactly) of least relative atmospheric 
motion before the generation of the cyclone. The views referred to as to the 
origin of cyclones will be found described at length at p. 250 of the “ Mete¬ 
orologist’s Vade-Mecum,” already referred to, where it is shewn that the ante¬ 
cedent conditions are calm weather over the sea, with a barometric pressure 
equal or nearly equal around the coasts. Under these circumstances a large 
quantity of vapour is produced by the solar heat, and this vapour being 
unable to escape is again condensed and liberates a great amount of latent 
heat over the place of its production ; the replacement of cooler by warmer 
air induces a local diminution of atmospheric pressure, and this causes a 
