( 14 ° ) 
[February, 
ACADEMIES AND SOCIETIES. 
Royal Society, January 15.— The papers read included one 
entitled “Results of and Inquiry into the Periodicity of Rainfall,” 
by G. M. Whipple, B.Sc., F.R.A.S., Superintendent of the Kew 
Observatory. The exceptionally heavy rainfall of the past spring 
and summer diredled a large amount of attention to the records 
of rainfall in this country, and more than one investigator stated 
that he had found a certain periodicity existing in the quantity 
of rain annually collected. Dr. Meldrum, Prof. Balfour Stewart, 
Mr. Hennessey, Prof. Stanley Jevons, Dr. Hunter, and others, 
have also widely published theories based upon the assumption 
that the variation in the yearly amounts of fall depends in some 
manner upon solar phenomena as exhibited by the changes in 
the appearance of the sun’s surface, thereby indicating a cycle 
of approximately ten or eleven years’ duration ; but even amongst 
the supporters of this so-termed “ sun-spot ” theory of rainfall 
there are differences of opinion as to the exacft nature of the 
influence an increase of sun-spots would exert upon the rainfall 
of any locality. Mr. G. J. Symons,* has partially investigated 
these theories, and shown the ten-year period does not obtain 
universally. With a view of dealing with the largest mass of 
material possible, the author took the long series of rainfall ob- 
servations made at Paris from 1689 to 1875, published by M. 
Marie Davy, in the “ Annuaire de l’Observatoire de Montsouris.” 
Starting with an assumption of a period, which he first made 
five years in length, and subsequently extended, he grouped all 
the observations together, first in five-year groups, then in six- 
year, then in seven-year, and so on, year by year, until he reached 
thirteen years. The means of these furnished a set of curves, 
showing the variation from the mean in the amount of annual 
rainfall for each of the years composing the series under consi- 
deration. The author’s results lead him to conclude that all 
predictions as to rainy or dry years, based upon existing mate- 
rials, must in future be considered as utterly valueless. 
Physical Society, January 24. — Mr. Grant read a paper and 
exhibited experiments on “ Induction in Telephonic Circuits.” 
* Nature, vol. vii., p. 143. 
