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\vhen I followed with my eye, thcfe ftreaks, or lymphatic vefiels, to 

 the part where they joined the cryltalline humour, they became ib 

 flender, that tiiey vanifhed from my fight. 



With regard to the before mentioned fcales or coats, which compofe 

 the cryftalline humour, I found them to be fo exceedingly thin, that, 

 meafuring them by my eye, I mufl fay, there were more than two 

 thoufand of them, lying one on another. For, when I had ftrippcd 

 the cryftalline humour of the membrane in wliich it was inclofed, I 

 found, that its axis or diameter where it was thickeft, (for it is not a 

 perfe61 globe, but fomewhat flattened ) was equal to two third parts 

 of an inch ; therefore, from the center to the circumference, is one 

 third of an inch ; and, as I have found by repeated experiments, that 

 fix hundred hairs of a man's head, are in breadth equal to an inch, 

 two hundred of them conftitute the third of an inch. Nov.', I have 

 feen, that where ten of the before mentioned fcales or coats lay 

 dole, one on another, they were not, altogether, equal to the diame- 

 ter of an hair ; therefore, if thcfe ten be mulciplied bj- two hun.dred, 

 it follows, as I have before mentioned, that the cryftalline humour 

 is, in its fubftance or thicknefs, con)pofed of more than two thoufand 

 fcales or coats : and laftly I faw, that each of thefe coats or fcales' 

 was formed of filaments or threads, placed in regular order, fide by 

 fide, each coat being of the thicknefs ef one fuch filament. 



In order to explain to the reader, the nature of this formation of the 

 cryftalline humour, that is, how it is compofed of fibres or filaments, 

 I have, in the following figures, reprefented thofe filaments by lines 

 drawn in a circle, as accurately as I was able; firft premifing, that in 

 Plate YIU. fig. 1. A B C reprefents the ct-yftalline humour, in an ox's 

 eye, of its natural fize ; B, is the place in that part of the tunica 

 cornea, or horny coat of the eye, through which the rays of light 

 pals. In the following figures, the natural dimenfions are increaied, 

 in order that the filaments of vv'hich the fcales or coats are compofed, 

 may be exhibited more diftinclly. 



'F f 2 



