Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . circumference of the iris. At the back cf ihe cryftalline, lies the vitreous hu-mour KIv, which is tranfpareiit like glafs, and islargca of all in quantity, filling the whole orb of the the eye to fee it from head to toot, as we do by thehand to feel it; and as the is informed bythe motion of the hand in one cafe, fo it is alfo by themotion of the eye in the other. In fig. 9. is
Encyclopaedia; or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of . circumference of the iris. At the back cf ihe cryftalline, lies the vitreous hu-mour KIv, which is tranfpareiit like glafs, and islargca of all in quantity, filling the whole orb of the the eye to fee it from head to toot, as we do by thehand to feel it; and as the is informed bythe motion of the hand in one cafe, fo it is alfo by themotion of the eye in the other. In fig. 9. is exhibited the manner of feeing thefame objea ABC, by both the eyes D and E atonce. Ail 148 When any part of the image cb a falls upon the op- Rcrve L, the correfp nding part of the object be- ^ rcomes invilible. On which acci unt, nature has wife-j ^^^ly pactd the optic nerve of each eye, not in the an[i-.,r(toii-rniddle of the bottom of tlie eye, but the fide the nofc ; fo that whatever part of the image fitlls t^ r*:upon the optic nerve o) one eye, may liot fall upon f,M^ij*the optic nefve of the cthsr. Thus the point a of the |j ,,,_ OPTIC S Plaie r C ClAWA. JiAv^f-\s:,j//„,Wt, s. 149 Proved byexperi-ment. Parti. OPTIC Of vifiun. image c h a falls upon the optic nerve of the eye 1), bccaufe, without this purticulvir encounter of the cp-*~~^^~~^ but not of the eye E; and the point c falls upon the tic nerves, where no vi;ion is made, tiie paper willoptic nerve of the eye E, but not of the eye D; and appear double, as is the cafe when the finger is nettherefore, to both eyes taiien together, the ob- rightly placed. jeiit ABC is vifible. M. obfcrves, that this improvement en The nearer any cbjefl Is to the eye, the larger his experiment, by M. Picard, is ingenious, but dif-is the angle under whicli it is feen, and the magni- ficult to execute, fincc the eves mult be confidcrably. tude under which it appears. Thu
Size: 1432px × 1744px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1700, bookdecade1790, bookidencyclopaedi, bookyear1798
