nd the Decoction of Roses, and the Solution of Copperis employ'd
about them, are endow'd each of them with its own Colour, there may be a
more noble Experiment of the sudden production of Blackness made by the
way mention'd in the Second Section of the Second Part of our Essays, for
though upon the Confusion of the two Liquors there mention'd, there do
immediately emerge a very Black mixture, yet both the Infusion of
_Orpiment_ and the Solution of _Minium_ were before their being joyn'd
together, Limpid and Colourless.

_EXPERIMENT III._

If pieces of White Harts-horn be with a competent degree of Fire distill'd
in a Glass-retort, they will, after the avolation of the Flegm, Spirit,
Volatile Salt, and the looser and lighter parts of the Oleagenous
substance, remain behind of a Cole-black colour. And even Ivory it self
being skilfully Burnt (how I am wont to do it, I have elsewhere set down)
affords Painters one of the best and deepest Blacks they have, and yet in
the Instance of distill'd Harts-horn, the operation being made in
Glass-vessels carefully clos'd, it appears there is no Extraneous Black
substance that Insinuates it self into White Harts-horn, and thereby makes
it turn Black; but that the Whiteness is destroy'd, and the Blackness
generated, only by a Change of Texture, made in the burnt Body, by the
Recess of some parts and the Transposition of others. And though I remember
not that in many Distillations of Harts-horn I ever sound the _Cap. Mort_.
to pass from Black to a true Whiteness, whilst it continu'd in Clos'd
vessels, yet having taken out the Cole-black fragments, and Calcin'd them
in Open vessels, I could in few hours quite destroy that Blackness, &
without sensibly changing their Bulk or Figure, reduce them to great
Whiteness. So much do these two Colours depend upon the Disposition of the
little parts, that the Bodies wherein they are to be met with do consist
of. And we find, that if Whitewine Tartar, or even the white Crystalls of
such Tartar be burnt without being truly Calcin'd, the _Cap. Mortuum_ (as
the Chymists call the more Fixt part) will be Black. But if you further
continue the Calcination till you have perfectly Incinerated the Tartar, &
kept it long enough in a Strong fire, the remaining _Calx_ will be White.
And so we see that not only other Vegetable substances, but even White
woods, as the Hazel, will yield a Black Charcoal, and afterwards Whitish
ashes; And so Animal substances natu