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On the Periodicity of Rainfall. 



[Apr. 16, 



Notwithstanding the exceptional localities of the stations, the above 

 results are generally in keeping with the Meldrum theory : the Dehra 

 observations for 1860 and prior years are unfortunately wanting ; but it 

 will be seen in Table I. that heavy falls occurred in the two years suc- 

 ceeding the epochal year 1860. 



5. It may, however, be questioned whether stations inland are ineligible 

 to test the theory under notice. No doubt far more rain falls on certain 

 parts of the globe than on others, and Mussoorie and Dehra are included 

 in the former : but a large rainfall is in fact a recommendation, presenting 

 as it does a large measure of the periodicity in question ; so that stations 

 under this condition appear highly eligible unless the rainfall is subject 

 to abnormal fluctuations, apart from the supposed influence of sun-spot 

 area; indeed, were it practicable to measure the total rainfall on the 

 whole globe, the total results would present the most effective argument 

 for periodicity. Projecting the facts of Table I., with the help of ordinates 

 and abscissae we obtain the appended diagram, where I am unable to 



introduce, in lieu of the year, numerical values of sun-spot areas from 

 want of complete results, such as those obtained by Messrs. De La Bue, 



