Mining Ordinances of Spain. 147 



mill. The mill is turned by a mule, and it is proper that it should 

 not always go round in the same direction, but that the motion 

 should be sometimes reversed : the object being-, that the Uses of 

 silver may fall to the bottom, and that the quicksilver contained 

 therein may not be lost by escaping with the slime or earthy residue, 

 which contains a proportion of silver, and also of quicksilver in a 

 minute state of division. To prevent this loss, it is therefore neces- 

 sary that the mixture should be kept briskly stirred in every part. 

 The slime being separated, the quicksilver remains at the bottom of 

 the vat, combined with the silver, in which state it is called amalgam. 

 The amalgam is taken out and placed in a linen bag, which being 

 suspended from the beams, the uncombined quicksilver runs out. 

 The part which remains in close combination is made up into small 

 cakes, which are formed into one large cake or pina (pine apple), 

 the size being adapted to the capacity of the brass cap or bell. 

 The latter consists of two pieces, the first of which is in the form of 

 a large basin, with a groove round the rim and a hole in the bottom. 

 On the inner part of the rim are three rests, on which is placed a 

 grating, made of iron bars, and upon that is set the pina or cake, 

 which is covered over with the cap. The cap is bell-shaped, and 

 fits into the groove of the vessel, which must be surrounded with 

 earth, and have a pan of water beneath it. The cap or bell remains 

 above, and is covered entirely with ignited charcoal, the heat from 

 which, raising the quicksilver in vapour, it finds its way into the 

 vessel, and passing through the hole in the bottom, is received in 

 the pan of water, and brought back into the state of fluid quicksilver. 

 Where caps of brass, copper, or iron, cannot be procured, they 

 must be made of the finest clay, adapted to resist the fire. 



* The proportion of silver returned, depends on the quality of the 

 ore ; sometimes the produce of silver is equal to an eighth part of 

 the quicksilver mixed in with the monton, sometimes a sixth part, 

 and sometimes a fifth part. The quicksilver separated in a liquid 

 state, still contains minute particles of silver, and it is set apart to 

 be used in working other montons, until consumed. This is the 

 only part really consumed ;* for the rest is either lost by being 

 converted into lis in the montons, or escapes with the slime, from 

 the agitation of the mill, being divided into the most minute and 

 imperceptible particles. A quintal of quicksilver is not wholly 

 consumed until after it has been employed seventeen times.' 



"When the ore is tolerably rich, and a more speedy return of 

 the silver is desired, another process is sometimes resorted to> 

 which is called the beneficio por cazo, or reduction by the cazo. 



* In Mexico, the difference between the quantity of quicksilver employed in 

 the process of reduction and the quantity recovered, is arbitrarily divided into 

 quicksilver consumed and quicksilver lost; a quantity equal or proportionate in 

 wi-ijrhtto the silver obtained, being said to be cowswrwct/, and the remainder of the 

 dciicient quicksilver to be /wiV, Trans, 



It* 



