1880.] in Relation to the Sun-spot Cycle. 79 



Table III. — Annual variation of pressure at Calcutta and Boml)ay. 



Years. 



(Jaicutta. 



Bornbaj^ 



Years. 



Calcutta. 



Bombay. 



1847 





— •013 



1858 



— •003 



+ •oos 



'48 





— •004 



'59 



+ ^009 



+ -004 



'49 





— -Oil 



'60 



— •019 



— •005 



'50 





— •001 



'01 



— •023 



— •012 



'51 





— 013 



'62 



— •017 



— •026 



'52 





— -004 



'63 



— •024 



— •017 ' 



'53 



—'•013 



+ -005 



'64 



— •Oil 



+ •OiS 



'54 



— -002 



— •005 



'65 



+ -ois 



+ -002 



'55 



+ -005 



+ -015 



'66 



+ -004 



+ 013 



'56 



— •0J4 



— •003 



'67 



+ -022 



+ 015 



'57 



— •013 



— •001 



'68 



+ ^022 



+ -027 



From these facts, it may be concluded that, in the Indo-Malayan 

 region, the pressure of the atmosphere is subject to a cyclical variation, 

 coinciding in period with that of the sun-spots ; and such that the epoch 

 of maximum pressure corresi^onds to that of minimum sun-spots and that 

 of minimum pressure to that of maximum sun-spots. When, however, we 

 turn to Western Siberia, we find an oscillation, not less, nay, far more 

 pronounced, and precisely of the opposite character ; the maximum of pres- 

 sure there coinciding with the maximum of sun-spots, and vice versa. The 

 station which exhibits this most prominently, is Ekaterinenburg at the 

 eastern foot of the Oural. But it is also very distinctly recognizable at 

 Bogolowsk to the North, at Slatoust to the South-west, at Barnoul at the 

 northern foot of the Altai, and, as Mr. Archibald pointed out some time 

 since in the pngos of 'Nature,' at St. Petersburg. The annual differences 

 at these stations are given in Table IV, and the corresponding curves in 

 the accompanying plate. 



