And such a Tryal hath
not ill succeeded, when insteed of the Colourless Oyl of Turpentine I took
a Yellow Mixture made of a good Proportion of Crude Turpentine dissolv'd in
that Liquor; and (if I mis-remember not) it also Succeeded better than one
would expect, when I employ'd an Oyl brought by Filings of Copper infused
in it, to a deep Green. And this (by the way) may be the Reason, why often
times when the Oyls of some Spices and of Anniseeds &c. are Distilled in a
Limbec with Water, the Water (as I have several times observ'd) comes over
Whitish, and will perhaps continue so for a good while, because if the Fire
be made too Strong, the subtile Chymical Oyl is thereby much Agitated and
Broken, and Blended with the Water in such Numerous and Minute Globules, as
cannot easily in a short time Emerge to the Top of the Water, and whilst
they Remain in it, make it, for the Reason newly intimated, look Whitish;
and perhaps upon the same Ground a cause may be rendred, why Hot water is
observ'd to be usually more Opacous and Whitish, than the same Water Cold,
the Agitation turning the more Spirituous or otherwise Conveniently
Dispos'd Particles of the Water into Vapours, thereby Producing in the Body
of the Liquor a Multitude of Small Bubbles, which interrupt the Free
passage, that the Beams of Light would else have Every way, and from the
Innermost parts of the Water Reflect many of them Outwards.
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