firmatively_, but in some Cases _Negatively_. As since Spirit of Wine,
and as far as I have try'd, those Chymical Oyles which Artists call
Essential, did not (when I us'd them as I had us'd the several Families of
Salts upon that Syrrup) turn Syrrup of Violets Red or Green, nor the
Solution of Sublimate White or Yellow, I inferr'd it may thence be probably
argued, that either they are destitute of Salt, or have such as belongs not
to either of the three Grand families already often mention'd. When I went
to examine the Spirit of Oak or of such like Concretes forced over through
a Retort, I found by this means amongst others, that (as I elsewhere show)
these Chymists are much mistaken in it, that account it a simple Liquor,
and one of their Hypostatical Principles: for not to mention what flegm it
may have, I found that with a few drops of one of this sort of Spirits
mix'd with a good proportion of Syrrup of Violets, I could change the
Colour and make it Purplish, by the affinity of which Colour to Redness, I
conjectur'd that this Spirit had some Acid Corpuscles in it, and
accordingly I found that as it would destroy the Blewness of a Tincture of
_Lignum Nephriticum_, so being put upon Corals it would Corrode them, as
common Spirit of Vinegar, and other Acid Liquors are wont to do. And
farther to examine whether there were not a great part of the Liquor that
was not of an Acid nature, having separated the Sour or Vinegar-like part
from the rest, which (if I mistake not) is far the more Copious, we
concluded as we had conjectured, the other or remaining part, though it had
a strong taste as well as smell, to be of a nature differing from that of
either of the three sorts of Salts above mention'd, since it did as little
as Spirit of Wine, and Chymical Oyls, alter the Colour either of Syrrup of
Violets or Solution of Sublimate, whence we also inferr'd that the change
that had been made of that Syrrup into a Purple Colour, was effected by the
Vinegar, that was one of the two Ingredients of the Liquor, which was wont
to pass for a Simple or Uncompounded Spirit. And, upon this account, 'twas
of the Spirit of Oak (and the like Concretes) freed from it's Vinegar that
I elsewhere told you, that I had not then observ'd it, (and I have repeated
the Tryal but very lately) to destroy the Caeruleous Tincture of _Lignum
Nephriticum_. But this onely, _en passant_; for the Chief thing I had to
add was this, That by the same way may be examin