424 PHYSICAL GEOGRAPHY OF THE SEA, AND ITS METEOROLOGY. 



search for them in the unequal distribution of land and water over 

 the two heniispheres. In one the wind is interrupted in its circuits 

 by the continental masses, with their wooded plains, their snowy 

 mantles in winter, their sandy deserts in summer, and their moun- 

 tain ranges always. In the other there is but httle land and less 

 snow. On the polar side of 40° S. especially, if we except the 

 smaU remnant of this continent that protrudes beyond that parallel 

 in the dhection of Cape Horn, there is scarcely an island. AU is 

 sea. There the air is never dry ; it is always in contact with a 

 vapour-giving surface; consequently, the winds there are loaded 

 with moistm-e, which, with every change of temperature, is either 

 increased by farther evaporation or diminished by temporary conden- 

 sation. The loropelling i^ower of the winds in the southern hemi- 

 sjphere resides chiefly in the laient heat of the vapour which they 

 such up from the engirdling sea 07i the polar side of Capricorn. 



824. The Storm and Eain Charts show that within the trade- 

 stom aiS^S^ ™^^ regions of both hemispheres the calm and rain 

 Charts. curvcs are symmetrical; that in the extra-tropical 

 regions the symmetry is between the cahn and fog curves; and 

 also, especially in the southern hemisphere, between the gale and 

 rain cmwes. Lieutenant Van Gough, of the Dutch Navy, in an 

 interesting paper on the connection between storms near the Cape 

 of Grood Hope and the temperature of the sea,* presents a storm 

 and rain chart for that region. It is founded on 17,810 observa- 

 tions, made by 500 ships, upon wind and weather, between 14° 

 and 32° E., and 33° and 37° S. By that chart the gale and rain 

 curves are so symmetrical that the phenomena of rains and gales 

 in the extra-tropical seas present themselves suggestively as cause 

 and effect. The general storm and rain charts of the Atlantic 

 Ocean, prepared at the National Observatory, Washmgton, hold 

 out the same idea. Let us examine, expand, and explain this fact. 



825. We ascribe the trade-winds to the equatorial calm-belt. 

 The "brave west But to what sliall WO ascribo the counter-ti'ades, par- 

 ^"efecu^rTin^he ticularly of the southern hemisphere, which blow 

 antarctic regions. wi\h as much regularity towards the pole as the 

 north-east trades of the Atlantic do towards the equator ? Shall wo 

 say that those winds are dra^n towards the south pole by heat^ 

 which causes them to exj^and and ascend in the antarctic regions ? 

 It sounds somewhat paradoxical to say that heat causes the winds 



* De Stormen nabij de Kaap de Goede Hope in verband beschouwd met de 

 Temperatuur der Zee. 



