Micrographia restaurata: or, the copper-plates of Dr. Hooke's wonderful discoveries by the microscope, reprinted and fully explained. Whereby the most valuable particulars in that celebrated author's Micrographia are brought together in a narrow compass; and intermixed occasionally, with many entertaining and instructive discoveries and observations in natural history ... / [Robert Hooke].

  • Hooke, Robert, 1635-1703.
Date:
1745
Catalogue details

Licence: Public Domain Mark

Credit: Micrographia restaurata: or, the copper-plates of Dr. Hooke's wonderful discoveries by the microscope, reprinted and fully explained. Whereby the most valuable particulars in that celebrated author's Micrographia are brought together in a narrow compass; and intermixed occasionally, with many entertaining and instructive discoveries and observations in natural history ... / [Robert Hooke]. Source: Wellcome Collection.

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    1 The Edge of a Razor. o Irregularity of the Type, the rough dawbing of the Printing-Ink thereon, and the Vari¬ ation made by the different Lights and Shadows. Nor is a Point made with a Pen, or by a Copper-Plate, at all lefs ill-fhapen and ugly ; nor can the fined Writing in the World ffand the Teft of this Indrument, but will appear before it like the bungling Scrawls of a School-Boy, made with Charcoal on a whited Wall. Jf p b | i / i * M I ^' ■ • A I* % - ~ - v. - v- • .. . • * •' .. PLATE I. FIG. 3. The Edge of a Razor. a^Razor^6 °* ^ ^ Figure reprefents the Edge (about half a Quarter of an Inch long) of a very J| . fharp Razor well fet upon a good Hone, and fo placed between the Objed-Glafs and the Light, that there appeared a Reflection from the very Edge, which is fhewn by the white Line a, by c, d, e, f When we fpeak of any thing as extremely keen, we ufually compare it to the Edge of a Razor j but we find, when examined thus, how far from Sharpnefs even a Razor's Edge appears: That it feems a rough Surface, of an unequal Breadth from fide to fide, but fcarce any where narrower than the Back of a pretty thick Knife: That it is neither fmooth, even, nor regular; for it is fomewhat fharper than elfewhere at d, indented about A bioadei and thicker about c} unequal and rugged about e, and mod: even between b9 and r', f though very far in any Place from being really draight. The Side immediately below the Edge, and what the naked Eye accounts a Part of it, <£> ^3 had nothing of that Polidi one would imagine Bodies fo finooth as a Hone and Oil fhould give it; but was full of innumerable Scratches eroding one another, with Lines here and there, more rugged and deep than the red, fuch as g, /j, y, k, o, occafioned pro¬ bably by fome fmall Dud falling on the Hone; or fome more flinty Part of the Hone itfelf. The other Part of the Razor L L, which had been polidied on a Grind-done anneared like a plowed Field, full of Ridges and Furrows. 5 ^ The irregular dark Spot m,, n, feemed to be a little Speck of Rud; corrofive Juices ge¬ nerally working in fuch a manner. J ° This Examination proves, how rough and unfeemly (had we microfcopic Eyes) thofe Things would appear, which now the Dulnefs of our Sight makes us think extremely neat and curious: And, indeed, it feems impoffible by Art to give a perfect Smoothnefs to any hard and brittle Body ; for Putty, or any other foft Powder, employed to polifh fuch Body, mud neceffarily confid of little hard rough Particles, each whereof cut ting its Way, mudconfequently leave fome kind of Furrow behind it. In fliort this Edge of a Razor, had it been really as the Microfcope thews it, would fcarce have ferved to rhnn Wood, indead of fhaving a Man’s Beard. Ch0P Jh.e .black Par] of this Figure is only defigned to make the red more vifible 1. he Scale is intended to meafure the Figure by. # An