COMMERCE. 



equator, preserve an equal temperature, which prevents them 

 from being condensed into true clouds. This is certainly the 

 cause of the extraordinary phenomenon of the total absence of 

 thunder and tempests ; and on this account it is, that a slight 

 covering of straw, which may absorb the dews and humidity 

 of the night, is considered as a sufficient shelter for the 

 dwellings. 



At the back of the cordillera of the coast, and in the inter- 

 mediate space between it and the more elevated one which is 

 named the royal cordillera, or the cordillera of the Andes, 

 are situated the provinces denominated ha Sierra^ extending 

 from the jurisdidtion of Chachapoyas to the great mineral terri- 

 tory of Potosi. The summits of their lofty mountains, never 

 freed from the immense weight of permanent snow that op- 

 presses them, are the origin and source of the waters which, 

 being precipitated in torrents, have gradually formed the deep 

 and rugged excavations of the earth, denominated, in com- 

 mon with the streams and rivulets that intersedl them, quebra- 

 das, and in which are cultivated all the vegetable produ6tions 

 necessary to the sustenance of man. The declivities of these 

 mountains afford a pasture for sheep ; but the superior part of 

 them consists of rocky surfaces, either totally bare, or covered 

 by a weak moss. 



From this description it may be deduced, that if, accord- 

 ing to the most precise calculations, a square league can com- 

 modiously maintain eight hundred persons, as is asserted by 

 Marshal Vauban, in his proje6l for a royal tithe, there are in 

 Peru trails of tv»'enty, and even thirty leagues in extent, which 

 would not repay the industrious efforts of the husbandman 

 with a single herb that would serve as pasture for the smallest 



animal. 



