The Fourth Part.

according to their own Rules to be look’d upon as very Compounded Bodies; but that among those very Salts that seem Elementary, because produc’d upon the Anatomy of the Bodies that yield them, there is not only a visible Disparity, but, to speak in the common Language, a manifest Antipathy or Contrariety: As is evident in the Ebullition and hissing that is wont to ensue, when the Acid Spirit of Vitrioll, for Instance, is pour’d upon pot ashes, or Salt of Tartar. And I shall beg leave of this Gentleman, sayes Carneades, casting his Eyes on me, to let me observe to You out of some of his papers, particularly those wherein he treats of some Preparations of Urine, that not only one and the same body may have two Salts of a contrary Nature, as he exemplifies in the Spirit and Alkali of Nitre; but that from the same body there may without addition be obtain’d three differing and Visible Salts. For He Relates, that he observ’d in Urine, not only a Volatile and Crystalline Salt, and a fixt Salt, but likewise a kind of Sal Armoniack, or such a Salt as would sublime in the form of a salt, and therefore was not fixt, and yet was far from being so fugitive as the Volatile salt; from which it seem’d also otherwise to differ. I have indeed suspected that this may be a Sal Armoniack properly enough so call’d, as Compounded of the Volatile salt of Urine, and the fixt of the same Liquor, which, as I noted, is not unlike sea-salt; but that it self argues a manifest Difference betwixt the salts, since such a Volatile salt is not wont to Unite thus with an ordinary Alcali, but to fly away from it in the Heat. And on this occasion I remember that, to give some of my Friends an Ocular proof of the difference betwixt the fixt and Volatile salt (of the same Concrete) Wood, I devis’d the following Experiment. I took common Venetian sublimate, and dissolv’d as much of it as I well could in fair Water: then I took Wood Ashes, and pouring on them Warme Water, Dissolv’d their salt; and filtrating the Water, as soon as I found the Lixivium sufficiently sharp upon the tongue, I reserv’d it for use: Then on part of the former solution of sublimate dropping a little of this Dissolv’d Fixt salt of Wood, the Liquors presently turn’d of an Orange Colour; but upon the other part of the clear solution of sublimate putting