This is that way of preparing sharp Waters usefull for the extractions of Copper and Gold. But as for Aqua Fortis requisite for the extracting of Silver, it cannot be prepared by this same Instrument, because it will corrode the Worm or Leaden Pipe, if it should pass through it, which the Spirit of Salt and Aqua Regis do not do.
N. B. When therefore you would make an Aq. Fortis, you must make you another twining Pipe or Worm of some other Metal which will not be preyed on by the Aqua Fortis, or else set some other Stone Vessels to the Nose of the Pipe that goes out of the Furnace.
It is also a thing possible to be done, to make such strong Acetum of Corn and Honey by the addition of some Salts, as that it shall not onely extract Gold and Silver, but also Copper and Lead out of metallick Veins or Earths.
Thus much may at present suffice to be spoken concerning the preparation of sharp Waters needfull for the extraction of Metals out of the Oars. The preparation [or Operation] it self follows.
How Metals are to be extracted out of their Earths or Oars, by the help of this Instrument.
The preparing or fitting of the Minera’s or metallick Earths for extraction, hath been described in the Appendix of the fifth part, and therefore needs not be repeated here.
But as we there showed, that the roasted [or calcined] and powdered Oars were to be put into Glass or Stone Cucurbits, that so they might be moistned with the sharp Waters, and be macerated [setting the Cucurbits] in warm Sand; so the very same thing is to be done here, this onely excepted, that [viz.] the earthen Pots supply the place of Glass and Stone Cucurbits, and the Instrument it self in which the extraction is made, performs the office of Sand: After the extraction, the Water impregnated with the extracted Metals is poured off, and the remaining matter it self is washt by pouring common Water thereupon, after such a manner as hath been prescribed in the Appendix of the fifth part.
By What means the Metals extracted by the dissolving Water out of the Oars are to be separated from that same sharp Water without any Detriment, nay rather with an augmentation of the said Water.
We have taught in the Appendix of the fifth part, that if a Man be not minded to precipitate the Metals out of the Solution by the contraries, viz. by Alkalizate Liquors, then there is no commodiouser and nearer way than that which separates the dissolving Water from the extracted Metal, by Distillation in Glass or earthen Vessels.
If now any one is minded to encrease his dissolving Water in this separation he may be Master of his desire by adding thereto common Salt, and drawing off the Water from it, which said Water will by this means be encreased and rendred stronger. And now there will come no inconvenience to the Metals themselves that are held up in that Water, in that some Salt remains with them, (no,) for in the reducing them, the said Salt gets them an easier and readier Fusion and Flux.