Tis also a common practice in _France_ to bury thin Plates of Copper in the Marc (as the French call it) or Husks of Grapes, whence the Juice has been squeez'd out in the Wine-press, and by this means the more saline parts of those Husks working by little and little upon the Copper, Coagulate Themselves with it into that Blewish Green Substance we in English call Verdigrease. Of which I therefore take Notice, because having Distill'd it in a Naked Fire, I found as I expected, that by the Association of the Saline with the Metalline parts, the former were so alter'd, that the Distill'd Liquor, even without Rectification, seem'd by smell and Tast, strong almost like _Aqua Fortis_, and very much surpassed the purest and most Rectifi'd Spirit of Vinager that ever I made. And this Spirit I therefore ascribe to the salt of the Husks alter'd by their Co-Mixture with the copper (though the Fire afterwards Divorce and Transmute them) because I found this later in the bottom of the Retort in the Forme of a _Crocus_ or redish powder: And because Copper is of too sluggish a Nature to be forc'd over in close Vessels by no stronger a heat. And that which is also somewhat Remarkable in the Destillation of good Verdigrease, (or at least of that sort that I us'd) is this, that I Never could observe that it yielded me any oyl, (unless a little black slime which was separated in Rectification may pass for Oyle) though both Tartar and Vinager, (especially the former) will by Destillation yield a Moderate proportion of it. If likewise you pour Spirit of Vinager upon Calcin'd Lead, the Acid Salt of the Liquor will by its Commixture with the Metalline parts, though Insipid, acquire in a few hours a more than Saccharine sweetness; and these Saline parts being by a strong Fire Destill'd from the Lead wherewith they were imbody'd, will, as I formerly also noted to a Different purpose, leave the Metal behind them alter'd in some qualities from what it was, and will themselves ascend, partly in the Forme of an unctuous Body or Oyle, partly in that of Phlegme; but for the greatest part in the Forme of a subtile Spirit, indow'd, besides divers new Qualities which I am not now willing to take notice of, with a strong smell very much other than that of Vinager, and a piercing tast quite differing both from the Sowerness of the Spirit of Vinager, and the Sweetness of the Sugar of Lead.