56 H. F. Blanford — The Winter Bains of Northern India. [March, 



transmission of this wave was the same as that of sound would only lead 

 to an approximate determination of the time of the great explosion at 

 Krakatoa. If that could be determined exactly by the stoppage of some 

 accurate clock in the immediate neighbourhood of the explosion, the ob- 

 servations of the time when the wave passed over different stations 

 might be usefully employed to determine the rate of propagation of an 

 atmospheric wave due to a very great disturbance. This might have a 

 practical as well as a scientific value, as, for example, in the case of the 

 propagation of a barometric fall due to the large atmospheric action over 

 the central area of a cyclone, which would probably evidently be propa- 

 gated in a similar way ; or the sudden downrush of a mass of air, as 

 perhaps occurs occasionally in nor' westers. 



The Rev. E. Lafont, s. j. said that it would be interesting to know 

 whether there were any data about the result of the meeting of the east 

 aud west parts of the waves. It was a matter of chance whether these 

 would interfere or not : if they had met in the same phase, their coalescence 

 might account for the triple recurrence of the barometric disturbance, 

 which had been noticed with some surprise by the President. 



Mr. H. Rivett-Carnac exhibited a Buddhist relic casket, containing 

 gold ornaments and coins, dug out recently at Domangurh near Gorruck- 

 pore and read a paper on the same, which will be published in Part I of 

 the Journal. 



Dr. Hoernle exhibited some original Persian letters addressed by 

 Lord Cornwallis and others to one of the wives of the Emperor of Delhi 

 at the end of last century. 



The following papers were read — 



1. The Theory of the Winter Bains of Northern India. — By H. F. 

 Blanford, F. R. S. Meteorological Reporter to the Government of India. 

 (With Isobar ic Charts). 



(Abstract.) 



At first sight, the occurrence of rain in Northern India at the season 

 when the N. E. or winter monsoon is at its height, seems to present a 

 meteorological paradox. The well-known theory of the winter monsoon 

 is that at that season the barometer stands highest in North Western 

 India where the air is cold and dry, and lowest in the neighbourhood of 

 the equator where it is warm and moist ; and therefore, in accordance 

 with elementary mechanical laws, the wind blows from the former to 

 the latter. But the precipitation of rain requires that the air should 



