Ch. X, SOUTH AMERICA. 459 



fo that at prefent only thofe of Guanfa Velica ^re 

 allowed to be worked ; by which means a flop has 

 been put to thofe frauds difcovered in the payments 

 of the fifrlis, the miners, inftead of applying to the 

 mine-offices within their department, or the principal 

 ftaple, fupplying themfelves with contraband mercury. 

 And the end has been fully anfwered with regard to 

 the revenue ^ frauds being now much more difficult, 

 and conlequently lefs frequent, fince the quickfilver 

 can be had only from one mine, than when feveral 

 were open. But at the fame time it is certain, that 

 this prohibition was the principal caufe of the decay 

 of the filver mines in the province of Quito : and had 

 the cafe been duly examined, many other remedies 

 might have been found to prevent thefe clandeftine 

 practices, befides an abfolute obllru6lion to fo great a 

 part of the riches of that country. 



It is the opinion of fome naturalifts, and the marks 

 of it are indeed very evident, that the ground on which 

 the city of Cuen^a ftands, is entirely an iron mine, 

 its veins iliewing themfelves in the chafms of fome 

 breaches ; and the pieces taken out of the floughs 

 prove it beyond difpute, not only by their colour and 

 weight, but by being attracted by the magnet, when 

 reduced to fmali pieces ; and many intelligent perfons 

 in thefe fpecies of mines affirm, that it not only is an 

 iron-mine, but aifo of extreme richnefs ; though this 

 has not been afcertained by experiment. 



It is alfo equally unqueftionable, that, were it pof- 

 fible to turn the induftry of the inhabitants into this 

 channel, mines of copper, tin, and lead, might alfo bf 

 difcovered, though no fuch thing is at prefent known. 

 But it is natural to fuppofe, that, where there are fo 

 inany mines of the mod precious metals, thofe of 

 copper and lead are not wanting. In the next 

 chapter I fliall give fome account of other mines ; 

 together with the quarries of curious ftone, and fe- 



