those of the Silk are small, round, hard, transparent, and to their bigness proportionably stiff, so as each filament preserves its proper Figure, and consequently its vivid reflection intire, though twisted into a thread, if not too hard; those of Flax are flat, limber, softer, and less transparent, and in twisting into a thread they joyn, and lie so close together, as to lose their own, and destroy each others particular reflections. There seems therefore three Particulars very requisite to make the so drest Flax appear Silk also when spun into threads. First, that the substance of it should be made more clear and transparent, Flax retaining in it a kind of opacating brown, or yellow; and the parts of the whitest kind I have yet observ'd with the Microscope appearing white, like flaw'd Horn or Glass, rather then clear, like clear Horn or Glass. Next that, the filaments should each of them be rounded, if that could be done, which yet is not so very necessary, if the first be perform'd, and this third, which is, that each of the small filaments be stifned; for though they be square, or flat, provided they be transparent and stiff, much the same appearances must necessarily follow. Now, though I have not yet made trial, yet I doubt not, but that both these proprieties may be also induc'd upon the Flax, and perhaps too by one and the same Expedient, which some trials may quickly inform any ingenious attempter of, who from the use and profit of such an Invention, may find sufficient argument to be prompted to such Inquiries. As for the tenacity of the substance of Flax, out of which the thread is made, it seems much inferiour to that of Silk, the one being a vegetable, the other an animal substance. And whether it proceed from the better concoction, or the more homogeneous constitution of animal substances above those of vegetables, I do not here determine; yet since I generally find, that vegetable substances do not equalize the tenacity of animal, nor these the tenacity of some purified mineral substances; I am very apt to think, that the tenacity of bodies does not proceed from the hamous, or hooked particles, as the Epicureans and some modern Philosophers have imagin'd; but from the more exact congruity of the constituent parts, which are contiguous to each other, and so bulky, as not to be easily separated, or shatter'd, by any small pulls or concussion of heat.
Observ. IV.Of fine waled Silk, or Taffety.
Fig. I.bigger magnifying Glass, which you see exhibits it like a very convenient substance to make Bed-matts, or Door-matts of, or to serve for Beehives, Corn-scuttles, Chairs, or Corn-tubs, it being not unlike that kind of work, wherewith in many parts in England, they make such Utensils of Straw, a little wreathed, and bound together with thongs of Brambles. For in this Contexture, each little filament, fiber, or clew of the Silk-worm, seem’d about the bigness of an ordinary Straw, as appears by the little ir-
