Micrographia: or some physiological descriptions of minute bodies made by magnifying glasses. With observations and inquiries thereupon / By R. Hooke.

Robert Hooke

Date:: 1665

Credit: Micrographia: or some physiological descriptions of minute bodies made by magnifying glasses. With observations and inquiries thereupon / By R. Hooke. Source: Wellcome Collection.

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$thofe of the «Sf/4 are fmallyound, hard, tranjparent, and to their bignels proportaonably ftijf, To as each filament preserves its proper Figure, and consequently its vivid refleftion intire, though twifted into a thread, if not too hard 5 thofe of FJax are flat, limber,flofter, and lefl tranjbarent, and in twifting into a thread they joyn,and lie fo clofe together,as to lofe their Own, and deftroy each others particular reflections. There feems there* fore three Particulars very requifite to make the fo dreftFlax appear Silk alfo when fpun into threads. Firft, that the fubftance ofitfhould be made more clear and tranjparent, Flax retaining in it a kind of opacating firownfor yellow 5 and the parts of the whiteft kind I have yet obferv a with the Microfcope appearing white, like flaw’d Horn or Glafs, rather then clear, like clear Horn or Glafs. Next that, the filaments fhould each of them be rounded, if that could be done,which yetis not fo very neceft fary, if the firft be perform’d, and this third, which is, that each of the fmall filaments be Jlifnedfor though they be fquare, or flat, provided they be tranjparent and ftiff, much the fame appearances mud neceflarily follow. Now, though I have not yet made trial, yet I doubt not, but that both thefe proprktiesmay be alfo induc’d Upon the Flax,and perhaps too by one and the fame Expedient, which fome trials may quickly inform any ingenious attempter of, who from the ufe and profit of fuch an Invention, may find fufficient argument to be prompted to fuch Inquiries. As for the tenacity of the fubftance of Flax, out of which the thread is made, it feetns much inferiour to that of Silk, the one being a vegetable, the Other an animal fubftance. And whether it proceed from the better con- coCdon, or the more homogeneous conftitution of animal fubftances above thofe of vegetables, I do not here determine 5 yet fince I ge¬ nerally.find, thu vegetable fubftances do not equalize the tenacity of ani¬ mal, nor thefe the tenacity of fome purified mineral - fubftances 5 I am very apt; to thinks that the tenacity of bodies docs not proceed from the ham0Hs,<ix hoobedp&n\cks, as the Epicureans, and fome modern Philo fo- phers have imagin’d 5 but from the more ex a (ft eongruity of the consti¬ tuent parts, which are contiguous to each other, and fo bulky, as not to be feafily feparated, or (batter’d, by any (mall pulls or eoncuflion of heati jynd [ ■ ‘fo crifi ’]r.' oi -radio t : rbod ■ bnid Ifa s. ■ e 3 : ' si 01 bt*:a I* His is the appearance of a piece of very fine Taffety-riband in the i ibigger magnifying Glais, which you fee exhibits it like a very con¬ venient (ubftance to make Bed-matts,or Door-matts of,or to forve for Bee¬ hives, Corn-fcuttles,Chairs, or Corn-tubs,it being not unlike that kind of work, Wherewith in many parts in England, they make fuch Utenfils of Straw,a little wreathed,and hound together with thongs of Brambles. For in this Contexture, each little filament, fiber, or dew of the Silk-worm, feem’d about the bignefs of an ordinary Straw, as appears by the little ir- • regular$