THE
PREFACE.

Having in convenient places of the following Treatise, mention'd the
Motives, that induc'd me to write it, and the Scope I propos'd to my self
in it; I think it superfluous to entertain the Reader now, with what he
will meet with hereafter. And I should judge it needless, to trouble
others, or my self, with any thing of Preface: were it not that I can
scarce doubt, but this Book will fall into the hands of some Readers, who
being unacquainted with the difficulty of attempts of this nature, will
think itn strange that I should publish any thing about Colours, without a
particular Theory of them. But I dare expect that Intelligent and Equitable
Readers will consider on my behalf: That the professed Design of this
Treatise is to deliver things rather _Historical_ than _Dogmatical_, and
consequently if I have added divers new _speculative_ Considerations and
hints, which perhaps may afford no despicable Assistance, towards the
framing of a solid and comprehensive Hypothesis, I have done at least as
much as I promis'd, or as the nature of my undertaking exacted. But another
thing there is, which if it should be objected, I fear I should not be able
so easily to answer it, and that is; That in the following treatise
(especially in the Third part of it) the Experiments might have been better
Marshall'd, and some of them deliver'd in fewer words. For I must confess
that this Essay was written to a private Friend, and that too, by snatches,
at several times, and places, and (after my manner) in loose sheets, of
which I oftentimes had not all by me that I had already written, when I was
writing more, so that it needs be no wonder if all the Experiments be not
rang'd to the best Advantage, and if some connections and consecutions of
them might easily have been mended. Especially since having carelessly laid
by the loose Papers, for several years after they were written, when I came