of the Bay of Bengal 223 



centrated over a portion of the Bay, accompanied by a strong 

 in-draught most marked from the Indian Ocean at the 

 entrance of the Bay. Mr. Eliot regards this heavy rainfall 

 as an immediate antecedent of a cyclone. For some years, 

 we believe, an opinion has existed that cyclones are connected 

 with rainfall. If our memory serves us correctly, we re- 

 member that some time in the early part of the decade 

 1850-60, a work on storms was published in which the 

 author laid some stress on the fact that cyclones mostly 

 originate in regions characterized by active precipitation of 

 aqueous vapour. A later writer, the Rev. Clement Ley, 

 speaks of extensive precipitation contributing to cyclonic 

 generation as follows : — " Extensive precipitation occurring 

 in a region of atmosphere previously approaching a con- 

 dition of tranquillity is the primary factor of every system of 

 baric depression with its resulting atmospheric circulation, 

 retrograde in the northern and direct in the southern hemi- 

 sphere." Mr. Meldrum's Mauritius Meteorological Results 

 for the year 1875 furnish some evidence which appears to 

 indicate that the connexion between rainfall and cyclones is 

 of a much stronger kind than he had before anticipated. He 

 says : — " The oft-observed fact that the dry weather in Mau- 

 ritius from December to April is accompanied by an absence 

 of hurricanes in the Indian Ocean, has been repeated in 1875. 

 It is remarkable that, while February is generally the wettest 

 month in Mauritius and the stormiest month in the Indian 

 Ocean, it was in 1875 the reverse in both these respects. 

 This seems to point to an intimate connexion between rainfall 

 and cyclones." 



Mr. Eliot, in discussing the principal facts of the Midna- 

 pore cyclone of October 1874, found that the rainfall on that 

 occasion was conterminous with the entire duration of the 

 cyclone. " It is," he says, " in this case, as in others, the 

 one meteorological factor, the introduction of which into the 

 previously existing conditions determined the commencement 

 of the cyclone ; and the intensity and situation of the rainfall 

 ran parallel with the intensity and position of the cyclone. 

 The evidence which the Midnapore cyclone thus affords of 

 the intimate connexion between rainfall and cyclone-generation 

 is very strong, and is almost equally conclusive in favour of 

 the condensation theory of the origin of cyclones." 



Connexion between Sun-spots and Cyclones. 

 Mr. Eliot, in commenting on the passage above quoted from 

 Mr. Meldrum, remarks :— " This statement of Mr. Meldrum's, 

 when it is remembered that he has upheld the parallel-wind 



R2 



