bottome of the Glass, there would soon appear four very pleasant and
distinct Colours; Namely, a Bright, but Dilute Colour at the picked bottome
of the Glass; a Purple, a little higher; a deep and glorious Crimson,
(which Crimson seem'd to terminate the operation of the Salt upward) in the
confines betwixt the Purple and the Yellow; and an Excellent Yellow, the
same that before enobled the whole Liquor, reaching from thence to the top
of the Glass. And if I pleas'd to pour very gently a little Spirit of Sal
Armoniack, upon the upper part of this Yellow, there would also be a Purple
or a Crimson, or both, generated there, so that the unalter'd part of the
Yellow Liquor appear'd intercepted betwixt the two Neighbouring Colours.

My scope in this 3d. Experiment (_Pyrophilus_) is manifold, as first to
invite you to be wary in judging of the Colour of Liquors in such Glasses
as are therein recommended to you, and consequently as much, if not more,
when you imploy other Glasses. Secondly, That you may not think it strange,
that I often content my self to rub upon a piece of White paper, the Juice
of Bodies I would examine, since not onely I could not easily procure a
sufficient Quantity of the juices of divers of them; but in several Cases
the Tryals of the quantities of such Juices in Glasses would make us more
lyable to mistakes, than the way that in those cases I have made use of.
Thirdly, I hope you will by these and divers other particulars deliver'd in
this Treatise, be easily induc'd to think that I may have set down many
Phænomena very faithfully, and just as they appear'd to me, and yet by
reason of some unheeded circumstance in the conditions of the matter, and
in the degree of Light, or the manner of trying the Experiment, you may
find some things to vary from the Relations I make of them. Lastly, I
design'd to give you an opportunity to free your self from the amazement
which possesses most Men, at the Tricks of those Mountebancks that are
commonly call'd Water-drinkers. For though not only the vulgar, but ev'n
many persons that are far above that Rank, have so much admir'd to see, a