150 Col. Francis Hall's Meteor olo<:ical Observations 



trary, the Cordillera recedes to some distance from the coast, 

 as is the case with parts of the Venezuelan chain, the inter- 

 mediate country is parched by a drought often of several 

 years. Maracaybo, and a considerable part of the province 

 of Coro, are instances, where sandy plains, scantily shaded by 

 Mimosas and thick plants, afford shelter and subsistence only 

 to flocks of goats and asses. The coast of Rio Hacha is 

 equally dry and sterile till it approaches the foot of the isolated 

 ridge of Santa Marta ; while the Goagira territory, interposed 

 between Rio Hacha and Maracaybo, is regularly inundated 

 every year, and consequently, though destitute of streams, 

 maintains considerable herds of cattle and horses, a circum- 

 stance to be ascribed to the vicinity of the Ocana branch of 

 the Andes, which extends, with its clouds and thick forests, 

 almost to the confines of this province. The whole Peruvian 

 coast from Payta to Lima is an additional instance of the 

 same fact, where the recession of the Andes from the coast is 

 marked by sandy deserts, which the industry of the Incas had 

 rendered productive by artificial irrigation. In the valleys, 

 and on the table lands of the mountains themselves, the cul- 

 minating summits produce great variations in the distribution 

 of moisture. The city of Caraccas, situated at the foot of the 

 Silla, has the benefit of a regular, though mild rainy season; 

 while within a league there are spots which suffer several years 

 of drought. Popayan, placed at the head of the sultry valley 

 of the Cauca, and surrounded by lofty paramos^ has nine 

 months of continued rains and tempests, attributable to the 

 clouds which are driven in opposite directions from the moun- 

 tains, till they encounter the hot ascending air of the valley. 

 In that part of the ancient kingdom of Quito now called the 

 Department of the Equator, the mass of Chimborazo inter- 

 rupts the passage of the clouds from south to north, so that 

 while the western slopes are deluged with rain, the elevated 

 plains of Riobamba to the east recall to the imagination of the 

 traveller the deserts of Arabia Petraea. Following the same 

 mountain-chain towards the city of Quito, we observe the 

 storms arrested between Cotopaxi and Pichincha over the 

 valley of Chillo, while two leagues further to the north the 

 climate of the village of Pomasqui is so dry as to have given 

 it tnfe name of Little Piura. 



The manner in which rain is formed and precipitated at 

 various elevations seems to illustrate and confirm the theory 

 of Leslie. In the regions oi paramos, i. e. from 12,000 feet 

 upwards, the encountering aerial currents, unless in the case 

 of some strong agitation of the mass of the surrounding atmo- 

 sphere, are of a low and nearly equal temperature. The 

 rains, inconsequence, assume the form of thick drizzling mists, 



