Liquor, till there remain’d a dry Calx
at the bottome, though this Precipitate were a Snow
White Body, yet upon pouring on it a large quantity
of fair Water, we did almost in a moment perceive it
to pass from a Milky Colour to one of the loveliest
Light Yellows that ever we had beheld. Nor is
the Turbith Mineral, that Chymists extol for its power
to Salivate, and for other vertues, of a Colour much
inferiour to this, though it be often made with a
differing proportion of the Ingredients, a more troublesome
way. For Beguinus,[22] who calls it Mercurius
praecipitatus optimus, takes to one part of Quick-Silver,
but two of Liquor, and that is Rectifi’d Oyl
of Sulphur, which is (in England at least) far
more scarce and dear than Oyl of Vitriol; he also
requires a previous Digestion, two or three Cohobations,
and frequent Ablutions with hot Distill’d Water,
with other prescriptions, which though they may conduce
to the Goodness of the Medicine, which is that he
aims at, are troublesome, and, our Tryals have inform’d
you unneccessary to the obtaining the Lemmon Colour
which he regards not. But though we have very
rarely seen either in Painters Shops, or elsewhere
a finer Yellow than that which we have divers times
this way produc’d (which is the more considerable,
because durable and pleasant Yellows are very hard
to be met with, as may appear by the great use which
Painters are for its Colours sake fain to make of that
pernicious and heavy Mineral, Orpiment) yet I fear
our Yellow is too costly, to be like to be imploy’d
by Painters, unless about Choice pieces of Work, nor
do I know how well it will agree with every Pigment,
especially, wich Oyl’d Colours. And whether
this Experiment, though it have seem’d somewhat
strange to most we have shown it to, be really of
another Nature than those wherein Saline Liquors are
imploy’d, may, as we formerly also hinted, be
so plausibly doubted, that whether the Water pour’d
on the Calx, do barely by imbibing some of
its Saline parts alter its Colour by altering its Texture,
or whether by dissolving the Concoagulated Salts,
it does become a Saline Menstruum, and, as
such, work upon the Mercury, I freely leave to you
(Pyrophilus) to consider. And that I may
give you some Assistance in your Enquiry, I will not
only tell you, that I have several times with fair
Water wash’d from this Calx, good store
of strongly tasted Corpuscles, which by the abstraction
of the Menstruum, I could reduce into Salt;
but I will also subjoyn an Experiment, which I devis’d,
to shew among other things, how much a real and permanent
Colour may be as it were drawn forth by a Liquor that
has neither Colour, nor so much as Saline or other
Active parts, provided it can but bring the parts
of the Body it imbibes to convene into clusters dispos’d
after the manner requisite to the exhibiting of the
emergent Colour. The Experiment was this.
[22] Beguinus, Tyr. Chy. Lib. 2º. Cap. 13º.


