446 THYSICAL GEOGRAPHY OF THE SEA, AND ITS METEOROLOGY. 



it to beast, bird, and plant, this waste water is collected into 

 antarctic icebergs, and borne away by the currents to more 

 genial climes, where the latent heat of fluidity which they dis- 

 pensed to the air in the frigid zone is restored, and w^here they 

 are again resolved into water, which, approaching the torrid zone 

 in cooling streams, again joins in the work and helps to cool the 

 air of the trade-winds, to mitigate climate, and moderate the 

 gale. For, if the water of ^southern seas were warmer, evapora- 

 tion would be greater ; then the S.E. trade-winds would deliver 

 vapour more abundantly to the equatorial calm belts ; this would 

 make precipitation there more copious, and the additional quan- 

 tity of heat set free would give additional velocity to the in- 

 rushing trade- winds. Thus it is, as has already' been stated, 

 that, parallel for parallel, between 40° or 50° north and south, 

 trans-equatorial seas are cooler than cis- equatorial ; thus it is that 

 icebergs are employed to push forward the winds in the polar 

 regions, to hold them back in the equatorial ; and thus it is that, 

 in contemplating the machinery of the air, we perceive how ice- 

 bergs are " coupled on," and made to perform the work of 

 regulator, with adjustments the most beautiful, and compensa- 

 tions the most exquisite, in the grand machinery of the atmo- 

 sphere. 



832. The antarctic calm place a region of constant precipitation. — 

 With this illustration concerning the dynamical force which the 

 winds derive, from the vapour taken up in one climate and ti-ans- 

 ported to another, we may proceed to sketch those physical 

 features which, being found in the antarctic circle, Avould be 

 most favourable to heavy and constant precipitation, and, conse- 

 quently, to the development of a system of aerial circulation 

 peculiarly active, vigorous, and regular for the aqueous hemi- 

 sphere, as the southern in contrast with the northern one may 

 be called. These vapour-bearing winds which brought the rains 

 to Patagonia are — 1 wish to keep this fact in the reader's mind 



the counter- trades (§ 257) of the southern hemisphere. As 



such they have to perform their round in the grand system of 

 aerial circulation, and as, in every system of aerial circulation 

 there must be some point or place at which motion ceases to be 

 direct and commences to be retrograde, so there must be a place 

 somewhere on the surface of our planet where these winds cease 

 to go forward, stop, and commence their return to the north; 

 and that place is, in all probahilitij, loithin the antarctic regions. Its 



