of hairs that had been Dyed, and
found them to be a kind of horny _Cylinder_, being of much about the
transparency of a pretty cleer piece of Oxe horn; these appear'd quite
throughout ting'd with the colours they exhibited. And 'tis likely, that
those hairs being boyl'd or steep'd in those very hot ting'd liquors in the
Dye-fat, And the substance of the hair being much like that of an Oxes
Horn, the penetrant liquor does so far mollifie and soften the substance,
that it sinks into the very center of it, and so the ting'd parts come to
be mix'd and united with the very body of the hair, and do not (as some
have thought) only stick on upon the outward surface. And this, the boiling
of Horn will make more probable; for we shall find by that action, that the
water will insinuate it self to a pretty depth within the surface of it,
especially if this penetrancy of the water be much helped by the Salts that
are usually mix'd with the Dying liquors. Now, whereas Silk may be dyed or
ting'd into all kind of colours without boiling or dipping into hot
liquors, I ghess the reason to be two-fold: First, because the filaments,
or small cylinders of Silk, are abundantly smaller and finer, and so have a
much less depth to be penetrated then most kind of hairs; and next, because
the substance or matter of Silk, is much more like a Glew then the
substance of Hair is. And that I have reason to suppose: First, because
when it is spun or drawn out of the Worm, it is a perfect glutinous
substance, and very easily sticks and cleaves to any adjacent body, as I
have several times observed, both in Silk-worms and Spiders. Next, because
that I find that water does easily dissolve and mollifie the substance
again, which is evident from their manner of ordering those bottoms or pods
of the Silk-worm before they are able to unwind them. It is no great wonder
therefore, if those Dyes or ting'd liquors do very quickly mollifie and
tinge the surfaces of so small and so glutinous a body. And we need not
wonder that the colours appear so lovely in the one, and so dull in the
other, if we view but the ting'd cylinders of both kinds with a good
_Microscope_; for whereas the substance of Hair, at best, is but a dirty
duskish white somewhat transparent, the filaments of Silk have a most
lovely transparency and cleerness, the difference between those two being
not much less then that between a piece of Horn, and a piece of Crystal;
the one yielding a bright and