222 GRINDING MILLS. 



CHAP. xiii. Of their Engines to grinde the mettall, and of 

 their triall of Silver. 



LIB. iv. To conclude this subject of silver and of rnettalls, there 

 remaines yet two things to speake of, the one is of their 

 engins and milles, the other of their essay or triall : I have 

 said before how they grinde their mettal, for the receiving 

 of the quicksilver, which is done with diverse instruments 

 and engins, some with horses like vnto hand-milles, others 

 like water-milles ; of which two sortes there are great num 

 bers. But for that the water they doe vse commonly is but 

 of raine, whereof they have not sufficient but three months 

 in the yeare, December, January, and February : for this 

 reason they have made Lakes and standing Pooles, which 

 containe in circuite about a thousand and six hundred 

 roddes, and in deapth three estados ; there are seven with 

 their sluces : so as when they have neede of any water they 

 raise vp a sluce, from whence runnes a little stroame of 

 water, the which they stoppe vppon holy-dayes. And when 

 the Lakes and Pooles doe fill, and that the yeare abounds 

 with mine, their grinding dooth then continue fixe or 

 seaven moneths ; so as even for silvers sake men desire 

 a good yeere of raiue in Potosi, as they doe in other places 

 for bread. There are some other engins in Tarapaya, which 

 is a valley three or foure leagues distant from Potosi, 

 whereas there runnes a river as in other parts. The differ 

 ence of these eugins is, that some goe with sixe pestels, 

 some with twelve, and others with fourteene. They grinde 

 and beate the mettal in morters, labouring day and night ; 

 and from thence they carry it to be sifted vpon the bankes 

 of the brooke of Potosi. There are forty eight water-mills, 

 of eight, ten, and twelve pestells, and foure on the other 

 side, which they call Tanacu-fiuiiu ; in the Cittie of Tara- 

 paya, there are two and twenty engins all vpoii the water ; 



