A Compleat System of Opticks in Four Books, Viz. A Popular, a Mathematical, a Mechanical, and a Philosophical Treatise. To which are Added Remarks Upon the Whole. By Robert Smith, Volumen1author, and sold there, 1738 - 171 páginas |
Dentro del libro
Resultados 1-5 de 44
Página iii
... apertures and eye - glasses of reflecting and refracting Telescopes , the theory of a reflecting Microfcope , having a concave spherical Speculum and a convex eye - glass , as propofed by Sir Ifaac Newton , is fully confidered , and ...
... apertures and eye - glasses of reflecting and refracting Telescopes , the theory of a reflecting Microfcope , having a concave spherical Speculum and a convex eye - glass , as propofed by Sir Ifaac Newton , is fully confidered , and ...
Página xii
... aperture and eye - glass of another telescope , thro ' which an object fhall appear as bright and distinct as in the given one , and magnified as much as shall be required . 140 CHAP . 8. Contains general Properties of Focus's and ...
... aperture and eye - glass of another telescope , thro ' which an object fhall appear as bright and distinct as in the given one , and magnified as much as shall be required . 140 CHAP . 8. Contains general Properties of Focus's and ...
Página 20
... aperture the diftinctness of the picture may be fenfibly improved . Because the rays which fall upon the margin of fuch a glafs are not refracted exactly to the fame points as thofe which fall nearer the middle of it : which will be ...
... aperture the diftinctness of the picture may be fenfibly improved . Because the rays which fall upon the margin of fuch a glafs are not refracted exactly to the fame points as thofe which fall nearer the middle of it : which will be ...
Página 25
... aperture . And fince the unequal de- grees of refrangibility of rays of different colours ( to be explained in the 6th chapter ) makes far greater aberrations from the focus , than those that are made by the fphericalnefs of the figure ...
... aperture . And fince the unequal de- grees of refrangibility of rays of different colours ( to be explained in the 6th chapter ) makes far greater aberrations from the focus , than those that are made by the fphericalnefs of the figure ...
Página 29
... aperture . For instance , when the eye approaches object from as near again to the object , the picture upon the retina becomes dou- ble in length and double in breadth , and confequently quadruple in fur- face ; for the furface would ...
... aperture . For instance , when the eye approaches object from as near again to the object , the picture upon the retina becomes dou- ble in length and double in breadth , and confequently quadruple in fur- face ; for the furface would ...
Términos y frases comunes
aberration alfo alſo altitude angle of incidence aperture apparent diftance apparent magnitude appear arch axis bafe becauſe breadth brightneſs cafe caufe cauftick cauſe circle cofine colours concave confequently convex Corol corona curve cylinders decreaſe defcribed denfity diameter diftinct diminiſhed emergent rays equal eye-glafs fame feen femidiameter fhall fhape fhews fide fince fingle firſt fituation fmall focal diſtance focus focuſes fome fquare ftraight fubtends fucceffive fuch fun's fuppofing furface given glaffes glafs glaſs globules Hence horizon incident rays increaſe interfection inverted laft laſt lefs lens light meaſured microſcope muſt obferved object obliquely optick paffing parallel parhelia parhelion pencil perpendicular placed plane pofition prifm produced propofition ratio reafon reflected refracted rays refrangible reprefented retina ſeen ſmall ſphere ſpherical tangent teleſcope thefe theſe thofe thoſe triangles vertical whofe
Pasajes populares
Página 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.
Página 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.
Página 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.
Página 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...
Página xiv - France and Ireland Defender of the Faith &c. To all to whom thefe Prefents fhall come Greeting.
Página 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.
Página 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...
Página 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.
Página 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.
Página 44 - A year after first seeing, being carried upon Epsom Downs, and observing a large prospect, he was exceedingly delighted with it, and called it a new kind of seeing.