Cu. VI. SOUTH AMERICA. 75 



From what has been said, it may be inferred, that 

 in a country or climate, where one and the same 

 wind perpetually prevails, there can be no formal 

 raiii ; and in order to form it, either the wind must 

 entirely cease, or an opposite wind juust arise, which 

 by checking the course of the vapours, brings them 

 into contact with those lately exhaled from the earth, 

 and causes them to condense in proportion as they 

 rise by the attraction of the sun, till being rendered 

 heavier than the air by which they were supported, 

 they descend in drops of water. 



On reconsidering the circumstances of what hap- 

 pened at Chccope, it will appear, that during the 

 whole day, the sky was clear, and that it was not 

 before five in the evening that the rain began, and 

 with it the violence of the wind. It should also be 

 observed that in the time of the brisas ia those cli- 

 mates where they are periodical, they blow strongest 

 between the setting and rising of the sun ; and this 

 happening in September and the following months, 

 forms the summer in Valles, when they enjoy clear 

 days and a lucid atmosphere. This vas the case at 

 Chocopeatthe time of that rain; for though the inha- 

 bitants did not precisely mention the season in which 

 that event happened, yet the several particulars re- 

 lated, especially that the south winds then prevailed 

 with an uncommon force, sufficiently indicate that 

 it was in the siunmer ; as this would not have been 

 at ail remarkable in winter, when they are very va- 

 riable and sometimes stormy. It may therefore be 

 safely concluded that these events happened during 

 the summer; and, byway of corollary, that the bri- 

 sas beiog stronger than usual, and advancing so far on 

 the continent as even to reach the south v.inds, they 

 were overpowered by them, and shifted tlieir point ; 

 but the succeeding south winds rendering it impossible 

 to reiurn in the same place, they left (heir formcf 

 ycgion aiid blew in a current nearer ihe earth. B^ 



whic¿ 



