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altitude angle of incidence angle of refraction aperture apparent brightness apparent distance apparent magnitude arch axis breadth cafe cause caustick circle of aberrations colours concave consequently contrary convex convex lens Corol corona curve cylinders decrease degrees density diameter diverge emergent rays equal eye-glass fame farther figure fixt focal distance focus of incident focuses fun's glass globules Hence hole horizon incidence and refraction incident rays inclined increase infinite inverted lens light medium microscope moon naked eye object-glass obliquely observed optick parhelia parhelion pass pencil of rays perpendicular picture placed plane point of incidence prism produced proportion Proposition rain-bow rays fall rectangle reflected reflecting telescope refracted rays refrangible retina seen semidiameter shews side sine of incidence sphere spherical surface subtended supposing tangent telescope triangles vertical white circle
Page 43 - He knew not the shape of any thing, nor any one thing from another, however different in shape, or magnitude, but upon being told what things were, whose form he before knew from feeling, he would carefully observe, that he might know them again; but having too many objects to learn at once, he forgot many of them : and (as he said) at first he learned to know, and again forgot a thousand things in a day.
Page 43 - One particular only (though it may appear trifling) I will relate. Having often forgot which was the cat, and which the dog, he was ashamed to ask ; but catching the cat (which he knew by feeling) he was observed to look at her steadfastly, and then setting her down, said, so puss ! I shall know you another time.
Page 74 - I speak of Light and Rays as coloured or endued with Colours, I would be understood to speak not philosophically and properly, but grossly, and accordingly to such Conceptions as vulgar People in seeing all these experiments would be apt to frame. For the Rays to speak properly are not coloured.
Page 43 - ... a glass of broken jelly, where a great variety of surfaces so differently refract the light, that the several distinct pencils of rays cannot be collected by the eye into their proper foci ; wherefore, the shape of an object in...
Page xiv - France and Ireland Defender of the Faith &c. To all to whom thefe Prefents fhall come Greeting.
Page 89 - Body by the vibrating Motion of the Parts of the Body, and gets beyond the reach of Attraction, being driven away with exceeding great Velocity.
Page 43 - ... (by which the rays cannot be brought into a focus upon the retina) they can discern in no other manner, than a sound eye can through a glass of broken jelly...
Page 44 - Before he was couched, he expected little advantage from seeing, worth undergoing an operation for, except reading and writing; for he said, he thought he could have no more pleasure in walking abroad than he had in the garden, which he could do safely and readily.
Page 44 - ... it; but his gratitude to his operator he could not conceal, never seeing him for some time without tears of joy in his eyes, and other marks of affection ; and if he did not happen to come at any time when he was expected, he would be so grieved, that he could not forbear crying at his disappointment.