The art of metals in which is declared the manner of their generation and the concomitants of them : in two books / written in Spanish by Albaro Alonso Barba ... curate of St. Bernards parish in the imperial city of Potosi, in the kingdom of Peru in the West-Indies, in the year 1640 ; translated in the year 1669 by the R. H. Edward, Earl of Sandwich.

CHAP. XV. Touching the causes and differences, of that which is called Lis.

QUicksilver dissolved, and divid∣ed into very subtile parts, is commonly called by the Refiners Lis, which shews its self like an eye-brow, in the matter Purunnia when the Oar is Ensayed; and from it the experienced Refiners take their indication of the quality of the Oar and condition of the Caxomes; it is caused by the often passing of it through the Oar (a thing inexcusable in the ordinary way of re∣fining) although it hath no ill quality at all, but if it hath Coperas in it, it will grind the Quicksilver in great extrea∣mity, as hath been said. If Quicksilver be without any foraign impression upon it, and be dissolved into Lis, which is white, 'tis called Lis of Quicksilver; Lis of other materials, is called that which is made by Quicksilver of Tin or Lead, and Lis of Silver is the fine, and

subtile parts of Silver, made by the re∣passing of the Quicksilver through the Oar, but not as yet joyned or incorpo∣rated with it; which when it is, they call by the name of Pella (which signi∣fies a Ball or Pellet) Quicksilver is susceptible of divers colours, which ap∣pears in the Lises according to the dif∣ferent matter which accompanies that Silver Oar into which it is thrown; these colours are reduced into three Genuses as it were, which comprehend under them several other Species.

Those three are

• Cleer.
• Lead Coloured.
• Spotted.

The Quicksilver looks cleer, either when the Oar hath no Silver at all in it, or when the Silver it contains is fine without any Alloy or mixture; in that case the Quicksilver will attract, and cloath it self with the dust of fine Silver, without losing the liveliness of its co∣lor; which when it changeth, they call it Leaden, for its likness unto the co∣lour

of that Mettal, although it always is accompanied with signs that the Oar contains Silver, unless it be that the Lead, for so they call it, proceed from false principles, and those have a mani∣fest cause, although little taken notice of, as well as the other proceedings in Refining, which hitherunto have been governed by chance. It is Copperas alone (the mortal enemy of Quicksil∣ver) which gives it the false colour of Lead, in like manner as it doth to other Mettals the colour of Copper; the o∣ther Lead colour is a certain sign of Sil∣ver, because ordinarily it is made in raw Oar, that is mixed with divers other bad things, the which attracting to it self the Quicksilver; the Quick∣silver lays hold of, and carries away both the Mettal, and also its bad com∣panions, who give it that strange co∣lour; this is the ground of what is trea∣ted of in the twelfth Chapter of this Book, and the reason of that assertion, that the black or obscure Lis, or colour of Quicksilver proceeds from Oar that is mixed with Iron; if the Quicksilver

have a deep Lead colour, then it hath Lead its self in its company, if it be some∣thing more clear, then it hath Tin, and if it look as if it were guilt a little, Cop∣per. Whether the Lis be of Quicksil∣ver, Silver, or of other materials is easie to be discerned, for the Lis of Quicksilver is very fine, white, but wanting quickness, and when it falls together with the water into the Tray, it doth not run up and down, but re∣mains as if it stuck to the bottom, and if you rub it with your finger, it will unite into lumps of Quicksilver. The Lis of Silver shines, and is like Pindust, or finer according to the richness of the Oar, when they let the water out from the Oar, it runs about the bottom of the Tray, and if you rub it with your fin∣ger, it will gather together into Pel∣lets; the Lis of other materials is as it were a middle thing between the other two, and being reduced into a body by rubbing it with ones finger, it unites it self with the touched Quicksilver.