that must be made by Incineration, I am the more invited to conclude,
that they may differ from one another, and consequently recede from an
Elementary Simplicity. And, if I could here shew You what Mr. _Boyle_
has Observ'd, touching the Various Chymicall Distinctions of Salts;
You would quickly discern, not only that Chymists do give themselves a
strange Liberty to call Concretes Salts, that are 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 some of the Volatile
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