residing within them might be dissolv'd and mix'd with the ambient juices of that place, and thereby those fibres and tender parts adjoyning become affected, and as it were corroded by it; whence, while that action lasts, the pains created are pretty sharp and pungent, though small, which is the essential property of an itching one.
That the pain also caused by the stinging of a Flea, a Gnat, a Flie, a Wasp, and the like, proceeds much from the very same cause, I elsewhere in their proper places endeavour to manifest. The stinging also of shred Hors-hair, which in meriment is often strew'd between the sheets of a Bed, seems to proceed from the same cause.
This Beard of a wild Oat, is a body of a very curious structure, though to the naked Eye it appears very slight, and inconsiderable, it being only a small black or brown Beard or Bristle, which grows out of the side of the inner Husk that covers the Grain of a wild Oat; the whole length of it, when put in Water, so that it may extend it self to its full length, is not above an Inch and a half, and for the most part somewhat shorter, but when the Grain is ripe, and very dry, which is usualy in the Moneths of July, and August, this Beard is bent somewhat below the middle, namely, about 25 from the bottom of it, almost to a right Angle, and the under part of it is wreath'd lik a With; the substance of it is very brittle when dry, and it will very easily be broken from the husk on which it grows.
If you take one of these Grains, and wet the Beard in Water, you will presently see the small bended top to turn and move round, as if it were sensible; and by degrees, if it be continued wet enough, the joint or knee will streighten it self; and if it be suffer'd to dry again, it will by degrees move round another way, and at length bend again into its former posture.
If it be view'd with an ordinary single Microscope, it will appear like a small wreath'd Sprig, with two clefts; and if wet as before, and then[errata 1] with this Microscope, it will appear to unwreath it self, and by degrees, to streighten its knee, and the two clefts will become streight, and almost on opposite sides of the small cylindrical body.
If it be continued to be look'd on a little longer with a Microscope, it will within a little while begin to wreath it self again, and soon after return to its former posture, bending it self again neer the middle, into a kind of knee or angle.
Several of those bodies I examin'd with larger Microscopes, and there found them much of the make of those two long wreath'd cylinders delineated in the second Figure of the 15. Scheme, which two cylinders re-
Errata
