fern VIII. SOUTH AMERICA. 99 



in all Valles, though at different depths in different 

 places. 



This plenty of fubterraneous ftreams is doubtlefa 

 of great advantage to the fertility of the country^ 

 particularly with regard to the larger plants, whofe 

 roots ftrike deepeft-, and this feems a bountiful in- 

 dulgence of the wife author of nature j who to pro- 

 vide againil the iierility which would certainly affeft 

 thefe countries from a want of water^ has fent a 

 fupply from the mountains, either in open rivers or 

 fubterraneous canals. 



The lands in the jurifdidion of Ghancay, like 

 the other parts of the eoafls of Peru, are manured 

 with the dung of certain fea birds, which abound 

 here in a very extraordinary manner. Thefe they 

 call Guanoes, and the dung Guano, the Indian name 

 for excrement in general. Thefe birds, after fpend- 

 ing the whole day in catching their food in the fea, 

 repair at night to reii on the iflands near the coail, 

 and their number being fo great as entirely to cover 

 the groundj they leave a proportionable quantity of 

 exc ement or dung. This is dried by the heat of the 

 fun into a cruft, and is daily encreafmg, fo that 

 notwiiihftanding great quantities are taken away, ic 

 is never exhaufted. Some v/iil have this Guano to 

 be only earth endowed with the quality of raifing a 

 ferment in the foil with which it is mixed. This 

 opinion is founded on the prodigious quantities 

 carried off from thofe iilands, and on the experi- 

 ment made by digging or boring, by which the 

 appearance at a certain depth, was the fame as 

 at the fuperficies ; whence it is concluded, that the 

 earth is naturally endowed with the heating quality ^ 

 of dung or Guano. This would feem lefs improba-J 

 ble, did not both its appearance and fmcll prove it to 

 be the excrement in queilion. I was in thefe iflands 

 when feveral barks came to load with it-, when the 

 infupportable fmell left me no room to doubt of the 



H 2 nature 



