322 THE CHEMISTRY OF CREATIOX. 



superadded to, those of heat and cold. Mr. 

 Eowell, whose views on the formation of rain, 

 and aqueous meteors generally, were mentioned 

 on a previous page, has also put forth some 

 curious speculations touching the origin of 

 irregular winds generally. He conceives that 

 as water in its vaporous condition occupies, 

 when suspended in the air, much more space 

 than when it falls as a rain-drop, it must in the 

 act of its falling cause a vacuum in the air 

 which must be filled up by a rush of air from 

 the surrounding districts. He supports his 

 views by various calculations" as to the average 

 vacuum per square mile caused by some heavy 

 storms of rain. He also mentions that in the 

 autumn of 1846, while France and other parts 

 of the Continent were deluged with rain, storms 

 of wind swept over England from the north- 

 west and west. 



It has also been thought that electricity, in 

 its various modifications, was in some manner 

 connected with the irregular movements of the 

 air. And it has been remarked as particularly 

 observable, that in the regions where the mag- 

 netic influence* of the earth is at the lowest 



* Although the phenomena of magnetism differ in several 

 curious particulars from those of the principle we commonly 

 call electricity, such as that developed by friction, both are 

 believed to be only the manifestations of one and the same 



