And I remember that very lately I did, for Tryal
sake, on a Tincture of _Benjamin_ drawn with Spirit of Wine, and brought to
be as Red as Blood, pour some fair Water, which presently mingling with the
Liquor, immediately turn'd the whole Mixture White. But if such Seeming
Milks be suffer'd to stand unstirr'd for a convenient while, they are wont
to let fall to the bottome a Resinous Substance, which the Spirit of Wine
Diluted and Weakned by the Water pour'd into it was unable to support any
longer. And something of Kin to this change of Colour in Vegetables is
that, which Chymists are wont to observe upon the pouring of Acid Spirits
upon the Red Solution of _Sulphur_, dissolv'd in an Infusion of Pot-ashes,
or in some other sharp _Lixivium_, the Praecipitated _Sulphur_ before it
subsides, immediately turning the Red Liquor into a White one. And other
Examples might be added of this way of producing Whiteness in Bodyes by
Praecipitating them out of the Liquors wherein they have been Dissolv'd; but
I think it may be more usefull to admonish you, _Pyrophilus_, that this
observation admits of Restrictions, and is not so Universal, as by this
time perhaps you have begun to think it; For though most Praecipitated
Bodyes are White, yet I know some that are not; For Gold Dissolv'd in _Aqua
Regis_, whether you Praecipitate it with Oyl of _Tartar_, or with Spirit of
_Sal Armoniack_, will not afford a White but a Yellow _Calx_.
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