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the influence is such as one magnet exerts upon another, or whether 

 the terrestrial magnetism is affected mediately, owing to a variation 

 in the intensity of the solar radiation, are points on which various 

 opinions are held." 



" The coincidences between solar and meteorological phenomena 

 are less certainly -determined ; but such as they are, they are of the 

 same character, viz. simple empirical coincidences, the physical 

 reason of which is still obscure ; and this obscurity cannot be re- 

 moved until we have answered beyond all cavil the fundamental 

 question, " Does the intensity of solar radiation vary pari passu 

 with the visible changes of his surface, and if so, what is the law 

 of that variation ?" The only attempts that have been made to 

 answer this question, by direct observation, are two — viz., a dis- 

 cussion by Mr. Baxendell of the recorded temperatures of sun-ther- 

 mometers at the Radcliffe observatory at Oxford, and at Eccles near 

 Manchester; and a discussion of the recorded radiation-tempe- 

 ratures at ten stations in different parts of India. In both cases 

 the conclusion was the same, and distinctly indicated. The sun 

 emits the more heat the greater the visible agitation of the photo- 

 sphere as indicated by the greater number of spots, of red flames 

 and faculse. But the sun-thermometer is justly regarded as an 

 instrument inadequate to decide a question so important as that 

 of the variations of the sun's heat." [In consequence of this inade- 

 quacy] " some persons have drawn the conclusion that the varia- 

 tion of the solar heat is the opposite of that indicated by the sun- 

 thermometer. Others, again, have arrived at a similar inference, 

 reasoning from the ascertained fact that sun-spots emit less heat 

 than the general solar surface ; and forgetting apparently that sun- 

 spots and faculse increase and decrease together. The question, 

 therefore, still remains for final decision ; and there is no more 

 important inquiry in the whole range of the science." 



In the introductory remarks to Mr. Hill's paper on the Variation 

 of Bainfall in Northern India, we have the following passage : — 

 "Early in 1877 Dr. W. W. Hunter published a pamphlet entitled 

 ' The Cycle of Drought and Famine in Southern India,' in which it 

 was shown that there is a remarkable tendency to a deficiency in 

 the rainfall of the city of Madras, at times when the surface of the 

 sun is free from spots — a phenomenon that had previously been 

 pointed out, though perhaps upon somewhat insufficient evidence, 

 by Mr. J. Norman Lockyer. Dr. Hunter also stated, upon the 

 authority of Sir W. Robinson of the Madras Council, that severe 

 famines and scarcities in various parts of the Southern Presidency 

 also tend to recur at intervals of about eleven years, this being the 

 approximate length of the cycle of the solar maculation." 



It having appeared from discussions by Mr. Blanford, Mr. Hill, 

 and Mr. E. D. Archibald, that although the registers examined 

 were not sufficient to establish a relation between sun-spot area 

 and rainfall, yet they seemed to lend some support to the theory that, 

 underlying very great irregular and non-periodic variations, there 

 is a fluctuation of the total annual rainfall coinciding approximately 

 with that of sun-spot frequency. Mr. Hill, in order to test the 

 soundness of this conclusion, and also of inquiring into the truth 



