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LXVII. Notices respecting New Books. 



I. Report on the Administration of the Meteorological Department of 

 the Government of India in 1877-78. Government Central 

 Press. 



II. Report on the Meteorology of India in 1877. By John Eliot, 

 M.A., Officiating Meteorological Reporter to the Government of 

 India. Third year. Calcutta, Office of the Superintendent of 

 Government Printing, 1879. 



III. Report on the Madras Cyclone of May 1877. By John Eliot, 

 M.A., Meterological Reporter to the Government of Bengal. Cal- 

 cutta, Office of the Superintendent of Government Printing, 

 1879. 



T^EOM the three works specified above we learn that the com- 

 -*- prehensive system of meteorological observation set on foot 

 about four years ago by the Government of India is in a satis- 

 factory state. The system embraces one hundred and eleven ob- 

 servatories scattered over an area of 28° 9' of latitude and 46° 51' of 

 longitude, ranging in vertical height to the extent of 11,532 feet, viz. 

 from 6 feet above mean sea-level at Saugor Island, in latitude 21° 

 39', longitude 88° 5', to 11,538 feet also above mean sea-level at 

 Leh,in latitude 34° 10', longitude 77° 42'. 



It is not improbable that the careful meteorological researches in 

 India may throw some light on the question of sun-spot frequency 

 and rainfall. Mr. Eliot in introducing his report has the following per- 

 tinent remarks : — " There can be no doubt that any periodicity in 

 the great cause of terrestrial atmospheric changes — solar radiation — 

 will tend to impress a corresponding periodicity upon the elements 

 of terrestrial meteorological observation. But so far as can be 

 judged from the observation of the magnitude of the sun-spots, the 

 cyclical variation of the magnitude of the sun's face free from spots 

 is very small compared with the surface itself ; and consequently, 

 according to mathematical principles, the effect on the elements of 

 meteorological observations for the whole earth ought also to be 

 small and proportional to the amount of variation of solar radiation. 

 That this is probably the case is indicated by a statement given in 

 Mr, Blanford's report of last year, that Mr. Meldrum's last and 

 most careful researches show that the total cyclical variation of the 

 rainfall does not exceed 15 per cent, upon the whole. This estimate 

 of the amount of the variation would very probably be considerably 

 reduced if it were possible to take into account the rainfall over 

 the oceanic as well as the land area ; for theory suggests that 

 excess in the one would probably be accompanied by deficiency in 

 the other. The known cyclical variation of the number of sun- 

 spots, and therefore of the amount of solar radiation, can therefore 

 at the best only account directly for a small and residual portion 

 of the actual irregularities of rainfall &c. observed in a large area 

 like India. It is however probable that at one part of the sun- 

 spot period one effect of the variation of solar radiation may be 



