100 SOUTH AMEEICA— THE ANDES EEGIONS. 



altogether, and sooner or later the balance cannot fail to be established betv^een 

 the inflow and the quantity carried off by evaporation, if indeed it is not already 

 established, as some suppose. At present the basin has an estimated area of 220 

 square miles, a mean depth of 100 feet (extreme, 300), and a rainfall of 73 inches, 

 which is rather more than that of Lake Geneva. 



III. 



Climate of Venezuela. 



Venezuela lies entirely within the equatorial zone, so that all the low-lying or 

 moderately elevated tracts are traversed by the thermal equator of 77° to 84° 

 Fahr., which is normal for the New World. But as in Mexico and other 

 tropical lands crossed by lofty ranges, the climate presents a succession of hot, 

 temperate, and cold zones, and in the Sierra Nevada de Merida the mean tempera- 

 ture is only four or five degrees above freezing-point at the altitude of 14,600 

 feet, which marks the limit of vegetation. Usually 1,800 to 2,000 feet, answering 

 to the isothermal of 77° Fahr., are taken as coinciding with the parting-line 

 between the hot and temperate lands, the coco and cacao plants ceasing to grow 

 above this elevation. The cold zone may be said to begin at about 7,200 feet, 

 where the mean temperature is 59° Fahr., too low for the banana, sugar-cane, 

 and manioc, which are here replaced by wheat, barley, and potatoes. 



But independently of the local temperatures, the great bulk of the inhabitants 

 are concentrated almost exclusively in the longitudinal valleys of the Andean 

 coast ranges, all the rest of the land being very thinly peopled. In fact, there 

 are scarely any whites or civilised Indians at all in that half of the republic which 

 lies south of Bolivar within the great bend of the Orinoco. By far the hottest 

 region are the llanos between the river and the foot of the mountains, where the 

 heat is not even tempered by the sea breezes. 



The most favoured districts are the plateaux and terraces rising above the hot 

 zone, and here are situated the towns of Caracas, Valencia, Barquisimeto, and 

 Merida, each with its own climatic peculiarities. Caracas, lying in a sort of 

 trough opening east and west between two parallel ranges, is exposed only to the 

 dry, hot morning breeze from the east, and to the vapour-charged afternoon breeze 

 from the west. The rains, which usually fall towards four or five o'clock in the 

 evening, are nearly always accompanied by electric discharges, although the 

 heaviest rains and fiercest thunderstorms are chiefly confined to the wooded moun- 

 tains of the north.* 



Lying altogether within the north torrid zone, Venezuela is comprised within 

 the domain of the north-east and east trade winds. But the normal currents are 

 endlessly modified by the marine inlets, the inequalities of the surface and other 

 local conditions. The " breeze," as the trade wind is called on the seaboard, 

 blows harder in the day than at night, when it is even replaced on the coast by a 

 land breeze due to the cooling of the ground after sunset. 



* Climatic conditions of Caracas :— Mean temperature, 72° Fahr. ; coldest month (January), 68° 

 Fahr.; hottest month (May), 93" Fahr.; mean atmospheric pressure, 27 inches; mean of rainy days, 

 74 ; mean annual rainfall, 30 inches. 



