OF THE EARTH^S ROTATION ON WINDS. 247' 



I have shown, in ^ Winds and Storms ' ^, that the trade- 

 winds are produced by a different cause to that which was 

 supposed to connect them with polar air passing over the 

 surface towards the equator; those winds, however, pass 

 over but a few degrees of latitude, where the rotatory velo- 

 cities of adjoining parts do not alter so much propor- 

 tionally within the same range of latitudes as they do 

 nearer to the poles. It is therefore about the latter parts 

 that we might, most confidently, expect to find the truth of 

 the hypothesis of retardation tested. But near the polar 

 regions few winds are found sufficiently continuous to en- 

 able us to trace the effects of varying rotatory velocities 

 of the surface upon their direction. Yet we are not with- 

 out cases in such parts that are suitable to throw light on 

 this subject. 



We are informed by navigators that from Victoria-land, 

 in (say) 74" of south latitude, a wind is found blowing to- 

 wards Tierra del Fuego, in 50° south. But Tierra del 

 Fuego, in 50° of latitude, being 24° further from the south 

 pole, has a more rapid rotation than Victoria-land in 74° ; 

 and if it were true that air passing from slower to quicker 

 rotating sui^faces was left palpably behind the surface of 

 the part over which it was passing, air flowing from the 

 south over the strip described should constitute an ap- 

 parent easterly wind moving in a direction the opposite 

 to that of Tierra del Fuego. But as it is asserted by 

 navigators to be not a south- e«5^, but a ^ou^h-west wind, 

 bearing ships towards Tierra del Fuego, it must move east- 

 ward faster than the surface over which it is passing, 

 although that surface is rotating with successively in- 

 creasing degrees of velocity. This case, then, affords 

 rather strong evidence of the fallacy of the prevailing 

 theory, that wind passing over a meridian from polar to 

 tropical parts is left behind the rotating surface. 



* Published by Longman and Co., London. 



