Maxima and certain Conditions of Temperature, fyc. 419 



More striking than any of these is the concurrent evidence afforded 

 by the diurnal variation of the Calcutta rainfall. Two series of data 

 have been published ; the one based on hourly observations of the occur- 

 rence of rain during twenty-one years,* the other giving the results of 

 seven years' records of a self-registering rain-gauge,f which affords 

 measurements of the quantities that feli in each hour as well as an 

 enumeration of rainy hours. The two series are generally accordant, 

 and exhibit a diurnal fluctuation of a remarkably pronounced 

 character. This differs at different seasons of the year, as might 

 indeed be anticipated, and it is in the rainy season, when the air is 



* ' Asiat. Soc. Bengal Journ.,' vol. 48, 1879, Part II, p. 41. 

 f ' Indian Meteor. Mem.,' vol. 4, p. 43. 



