Notices respecting New Boohs. 379 



of the supposed cyclical variation of the annual rainfall, examined 

 all the available rainfall registers for the North-west Provinces and 

 Oudh, as well as many others placed at his disposal by the courtesy 

 of the Meteorological Eeporter to the Government of India, and of 

 the Secretary to the Financial Commissioner of the Punjab, from 

 which Mr. Hill selected the registers of twenty representative sta- 

 tions, several extending over a period of twenty or more consecutive 

 years. The country included by the discussion extended over 

 more than eleven degrees of latitude and twenty-four degrees of 

 longitude. 



In carrying out this discussion Mr. Hill divided his material 

 into two series, viz. summer and winter rainfall. The summer 

 rains afford a result fairly accordant with the assumption that there 

 is an eleven-year cycle of rainfall similar to that obtained by Mr. 

 Blanford ; but he has this remark : — "Neither Mr. Blanford's result 

 nor this can therefore be said to lend unequivocal support to Mr. 

 Meldrum's hypothesis; for the character of the oscillation in the case 

 of the rainfall is very different from that of the sun-spots — the 

 fall from maximum to minimum occurring in three years and the 

 rise from minimum to maximum occupying eight, whereas in the 

 average sun-spot cycle the fall occupies seven years and the rise 

 only four." 



The discussion of the winter rainfall furnishes a considerable 

 degeee of uniformity as regards the epoch of maximum and mini- 

 mum of four cycles of eleven years each, from 1834 to 1877, and is 

 illutrated by a series of curves, of which that of Wolf's sun-spot 

 numbers (inverted) for the same cycles, is compared with that of the 

 winter rains, with the following result : — " The maximum of winter 

 rainfall would therefore appear to be reached on the average rather 

 more than a year before the minimum of sun-spots ; and the mini- 

 mum rainfall appears either to coincide with, or to follow the 

 maximum of sun-spots at about an equal interval. The two phe- 

 nomena cannot, therefore, be directly related to each other as cause 

 and effect, though they may both be the effects of a common cause." 



Since the establishment by General Sir Edward Sabine of a 

 connexion between the variation of sun-spots and that of terres- 

 trial magnetism, to which allusion is made in Mr. Blanford's Report, 

 several other phenomena have been considered to be associated in 

 a somewhat similar manner with variations in the sun's photo- 

 sphere. We have been able to ascertain from various sources the 

 following : — 



Sun-spot prevalence accordant with Authority. 



1. Position of inferior planets Dr. De La Eue. 



2. Terrestrial magnetism Gen. Sabine. 



3. Aurorse. 



4. Barometric variations ...... {^ cumbers. 



f L.Trouvelot. 



5. Eainfall, storms, cyclones, &c. ... \ C. Meldrum. 



[ J. N. Lockyer. 

 2E2 



