^86 ulloa's voyage to south America, 



known in the country of Valles, there are wetting fogs called garuas, which continue 

 the greateft part of the winter ; but are never feen in fummer. 4. When the garuas 

 fall, it is obferved that the clouds, mift, or vapours, which rife from the earth, re- 

 main almofl contiguous to its furface ; and the fame fog which is converted into a 

 garua, begins by a moift air, till the humidity gradually increafmg to its greateft con- 

 denlation, the fmall drops which fall are eafily diftinguifliable. This is fo natural, that 

 it is known in all other countries fubjed to any degree of cold, and, confequently, not 

 to be wondered at in this. 



I give the name of cloud, mift, or vapours, to that which produces the garua or 

 fmall rain ; for though there may be fome accidental diftindions between thefe three 

 kinds, they are not fuch as caufe any material difference : the fog being only the 

 vapour condenfed more than when it firft rofe ; and the cloud only a fog elevated to 

 a greater height, and ftill more condenfed than the former : fo that in reality they 

 may all be confidered as one and the fame thing, differing only in degrees of denfity, 

 and therefore it is of little importance whatever name it is called by. 



5. The rays of the fun during the fummer, caufe a prodigious heat all over Valles, 

 and the more fo as they are received upon a fandy foil, whence they are ftrongly rever- 

 berated, the winds being at the fame time very weak. Hence it appears, that the 

 fecond hypothefis above related, is not founded on truth ; for if the force or agitation 

 of the fouth winds be the caufe which hinders the vapours from rifmg to the height 

 neceffary for forming rain, this caufe generally ceafmg in the fummer, the rain might 

 be expeded to defcend ; whereas quite the reverfe happens, the garuas being then 

 much lefs common. 6. Particular times have been known when the nature of the 

 country departing as it were from its ufual courfe, formal fhowers have fallen, as we 

 have already mentioned (chap, i.) in defcribing the towns of Chocope, Truxillo, Tum- 

 bez, and other places ; but with this fmgularity, that the winds continued at fouth, 

 and blew much ftronger during the time of the rain, than is ufual either in winter or 

 fummer. 



Thefe fix preliminary principles are fo common to this climate, that they may be 

 applied to all the places mentioned in this chapter ; and are the only guides that muft 

 be followed in determining the true caufe why it does not rain in Peru as in Europe, or, 

 more properly, as is common in the torrid zone. 



It will readily be granted, that the wind blows more ftrongly in fome regions of the 

 atmofphere than in others, experience itfelf having fuffiiciently proved this to be fa£l ; 

 as on high mountains, along whofe fummits a ftrong wind is felt, when at the foot 

 hardly any can be perceived ; at leaft, we found this to be the cafe in all the mountains 

 of the Cordilleras, one of the greateft inconveniences to us being the ftrength of the 

 wind. And, indeed, this is every where fo common, that any perfon may be convin- 

 ced of it by only afcending a high tower, then he will foon perceive the difference be- 

 tween the ftrength of the wind at the top and at the bottom. I am not ignorant that 

 fome have endeavoured to prove, that on the lantl this proceeds from the inequalities 

 of its furface, which hinder the winds from blowing in the plains or low countries with 

 that force which is felt on eminences ; but the fame thing happening at fea, as experi- 

 ence has abundantly proved, it appears beyond difpute, that the furface is not the place 

 where the wind exerts its greateft force. This being granted, it may be confidently 

 afferted, that the fouth winds blow with the greateft force in a portion of the atmof- 

 phere at fome diftance from the earth ; but not generally higher than that in which the 

 rain is formed ; or where the aqueous particles unite fo as to form drops of any fenfi- 

 ble gravity or magnitude. In this country, therefore, the clouds or vapours elevated 



3 above 



