of them (especially the Beard of a wilde
_Oat_, and of _Mosk-grass_ seed) seeming to have two kind of substances,
one that is very porous, loose, and spongie, into which the watry steams of
the Air may be very easily forced, which will be thereby swell'd and
extended in its dimensions, just as we may observe all kind of Vegetable
substance upon steeping in water to swell and grow bigger and longer. And a
second that is more hard and close, into which the water can very little,
or not at all penetrate, this therefore retaining always very neer the same
dimensions, and the other stretching and shrinking, according as there is
more or less moisture or water in its pores, by reason of the make and
shape of the parts, the whole body must necessarily unwreath and wreath it
self.

And upon this Principle, it is very easie to make several sorts of
contrivances that should thus wreath and unwreath themselves, either by
heat and cold, or by driness and moisture, or by any greater or less force,
from whatever cause it proceed, whether from gravity or weight, or from
wind which is motion of the Air, or from some springing body, or the like.

This, had I time, I should enlarge much more upon; for it seems to me to be
the very first footstep of _Sensation_, and Animate motion, the most plain,
simple, and obvious contrivance that Nature has made use of to produce a
motion; next to that of Rarefaction and Condensation by heat and cold. And
were this Principle very well examin'd, I am very apt to think, it would
afford us a very great help to find out the _Mechanism_ of the Muscles,
which indeed, as farr as I have hitherto been able to examine, seems to me
not so very perplex as one might imagine, especially upon the examination
which I made of the Muscles of _Crabs_, _Lobsters_, and several sorts of
large Shell-fish, and comparing my Observations on them, with the
circumstances I observ'd in the muscles of terrestrial Animals.

Now, as in this Instance of the Beard of a wilde _Oat_, we see there is
nothing else requisite to make it wreath and unwreath it self, and to
streighten and bend its knee, then onely a little breath of moist or dry
Air, or a small _atome_ almost of water or liquor, and a little heat to
make it again evaporate, for, by holding this Beard, plac'd and fix'd as I
before directed, neer a Fire, and dipping the tip of a small shred of Paper
in well rectify'd spirit of Wine, and then touching the wreath'd
_Cylindrical_