THE WINDS OF THE SOUTHERN HEMISPHERE. 



439 



the North Atlantic. But as it is, the contrast is very striking. 

 In some aspects, the meteorological agents of the two hemi- 

 spheres, especially those forces which control the winds and the 

 Aveather, differ very much. The difference is so wide as to sug- 

 gest greater regularity and rapidity of circulation on one side of 

 the equator than on the other. 



822. Calms in ilie two liemispheres. — Average Number of Calms to the 1000 Oh- 

 ser rations heticeen the Parallels o/ 30^ and 55°, in the Noiih and South Atlantic, 

 and between the Parallels 0/30^ and 60° in the North and South Pacific Oceans, 

 a^ shown by the Pilot Charts. 



Each one of these observations embraces a period of eight hours ; 

 the grand total, if arranged consecutively, with the observations 

 drawn out each to occupy its period separately, would be equal 

 to 373 years. They exhibit several curious and suggestive facts 

 concerning the difference of the atmospherical stability in the 

 two hemispheres. 



823. The propelling power of the idnds. — If we would discover 

 the seat of those forces which produce this difierence in the 

 dynamical status of the two great aerial oceans that envelop our 

 planet, we !^hould search for them in the unequal distribution of 

 land and water over the two hemispheres. In one the w^ind is 

 interrupted in its circuits by the continental masses, yviih their 

 wooded plains, their snowy mantles in winter, their sandy 

 deserts in summer, and their mountain ranges always. In the 



