A reply to Mr. Robin's remarks on the Essay upon distinct and indistinct vision published at the end of Dr. Smith's Complete system of optiks / by James Jurin.
- James Jurin
- Date:
- 1739
Licence: Public Domain Mark
Credit: A reply to Mr. Robin's remarks on the Essay upon distinct and indistinct vision published at the end of Dr. Smith's Complete system of optiks / by James Jurin. Source: Wellcome Collection.
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![E r $ oi ai \s - c cl h e At- t,s ] i. e. if A and E be die middle points of the two fits of tranfmiffion and reflexion, the ray, in ap- J\ preaching the point E, lhall at be more difpofed to reflexion than at s, at y more than at S', at 0 more than at y, and at a more than at 0. Alfo, when the ray has pall the point E, and is receding from it, it lhall at a be more difpofed to reflexi¬ on than at b, and b more than at c, at c more than at d, and fo on. Proposition IV. While a ray becomes more and more difpofed to reflexion, it becomes lefs and lefs difpofed to tranfmiffion: and while it becomes lefs and lefs dif¬ pofed to reflexion, it becomes more and more difpofed to tranfmiffion. For inftance, a ray palling from A to E, is more difpofed to reflexion and lefs to tranfmiffion at S' than at e, at y than at d', at 0 than at y, at a than at /?, and at E than at a. And having pafs’d the point E it is lefs difpofed to reflexion and more to tranfmiffion at a, than at E, at b than at <3, at c than at E4- b, and fo on, till it arrives at A, where it is the moft of all difpofed to tranfmiffion and the leafl: to reflexi¬ on. Proposition V. When a ray is moft ftrongly difpofed to re¬ flexion, it may be refle&ed back from the fur- face](https://iiif.wellcomecollection.org/image/b30780287_0026.jp2/full/800%2C/0/default.jpg)
