A choice collection of rare secrets and experiments in philosophy as also rare and unheard-of medicines, menstruums and alkahests : with the true secret of volatilizing the fixt salt of tartar / collected and experimented by the honourable and truly learned Sir Kenelm Digby, Kt., Chancellour to Her Majesty the Queen-Mother ; hitherto kept secret since his decease, but now published for the good and benefit of the publick by George Hartman.

About Vitrum Antimonii, and the Tincture of it.

MOnsieur Borel told me, that he had observed this in making the Tincture of {antimony} (by distilled Vinegar upon the Glass of {antimony}) that when he went to dulcifie the Salt that remaineth in the Tincture after the distilled Vinegar is evaporated away (as Bas. Val. teacheth) he could never perceive that the {water} evaporating carried away the remaining Salt of the Vinegar, but still when the {water} was gone, and left the Powder dry, it was as salt as ever before, and was of a brown gray colour. But this he observed, that af∣ter four or five times dissolving in {water} and evaporating, the Tincture Precipitated down very red, and the Salt of the distilled Vinegar remained dissolved in the {water}, so that he then poured off the {water}, and dryed the Powder, which then was exceeding red, and perfectly dulcified: But after thus severing of the Salt from it, S. V. would not touch upon it, and extract it any further: Perad∣venture a Tartarized S. V. will do it.

He also told me, that in making the Vi∣trum Antimonii for this Work, the Mystery to have it certain and constant, consisteth in this; That after you have Calcined your {antimony}

by long and gentle evaporation and stirring, so that it smoak no more; and when you have put it in the Crucible to melt into Glass, you must put to it a little piece of a Coal to burn with the {antimony}, and set the Sul∣phur of it on fire, which will make a little Regulus fall down to the bottom, and the Glass will be pure clear and red, whereas if no Coal fall or be put in, it will be black and muddy: And that which maketh this Work of Vitrifying the {antimony} prove uncertain, is, that sometimes some Coals fall into the Crucible (as one gives great heat) without the Artists taking notice, and then the Work proveth well, but if no wooden Coals fall in, the Glass proveth not as it should.

Monsieur le Fevre told me, that when he makes the Tincture of Vitrum Antimoniii, be observes, as Monsieur Borel saith, that if the extract of it made by distilled Vine∣gar be perfectly dulcified from all saltness, the S. V. will not touch upon it; and if it be put upon it in dry Powder, containing the Salt of the distilled Vinegar with the Tincture of the {antimony}, it will draw with the Tincture some nocuous Spirits from the Salt; therefore the doth thus: Evaporate fair {water} from it two or three times, the last time leave it very moist; then put S. V. upon it, and it will presently impregnate it self with the Tincture.