demand, how that Dispersion comes to destroy their Blackness, but by making
such a Local Motion of their parts, as destroys their former Texture? which
may be a Matter of such moment in cases like ours, that I remember that I
have in few houres, without addition, from Soot it self, attain'd pretty
store of Crystalline Salt, and good store of Transparent Liquor, and (which
I have on another occasion noted as remarkable) this so Black Substance had
its Colour so alter'd, by the change of Texture it receiv'd from the fire,
wherewith it was distill'd, that it did for a great while afford such
plenty of very white Exhalations, that the Receiver, though large, seem'd
to be almost fill'd with Milk.

Secondly, But were it granted, as it is in some cases not Improbable, that
divers Bodies may receive a Blackness from a Sootie Exhalation, occasion'd
by the Adustion of their Sulphur, which (for the Reasons lately mention'd I
should rather call their Oyly parts;) yet still this account is applicable
but to some Particular Bodies, and will afford us no General Theory of
Blackness. For if, for example, White Harts-horn, being, in Vessels well
luted to each other, expos'd to the fire, be said to turn Black by the
Infection of its own Smoak, I think I may justly demand, what it is that
makes the Smoak or Soot it self Black, since no Such Colour, but its
contrary, appear'd before in the Harts-horn? And with the same Reason, when
we are told, that torrify'd Sulphur makes bodies Black, I desire to be told
also, why Torrefaction makes Sulphur it self Black? nor will there be any
Satisfactory Reason assign'd of these Quaeries, without taking in those
Fertile as well as intelligible Mechanical Principles of the Position and
Texture of the Minute parts of the body in reference to the Light and the
Eye; and these applicable Principles may Serve the turn in many cases,
where the Adustion of Sulphur cannot be pretended; as in the appearing
Blackness of an Open window, lookt upon at a somewhat remote distance from
the house, as also in the Blackness Men think they see in the Holes that
happen to be in White linnen, or Paper of the like Colour; and in the
Increasing Blackness immediatly Produc'd barely by so rubbing Velvet, whose
Piles were Inclin'd before, as to reduce them to a more Erected posture, in
which and in many other cases formerly alleg'd, there appears nothing
requisite to the Production of _the_ Blackness, but the hindering of the
in