LightA. and C. Black, 1884 - 276 páginas |
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Términos y frases comunes
absorption amount angle of incidence appear axis body bright bright bands centre circle colours crystal curvature cylinder dark depends diameter direction disk distance divergence double refraction ellipse equal explained fact flame Fraunhofer lines Geometrical Optics give given glass greater heat Hence homogeneous light Huygens Iceland spar illuminated incident ray law of refraction length lens lines luminous point medium mirror motion nearly Newton Nicol object observed optics ordinary ray parallel rays particles passing path perpendicular phenomena placed plane of polarisation plane of reflection plate polarised light portion position prism produced propagated radiation radius rainbow rays falling reflected ray refractive index refrangible result right angles rotation screen seen shows source of light spectra spectrum speed of light spherical spherical angle stars sunlight suppose surface temperature thickness tion undulatory theory uranium glass velocity vertical vibrations wave wave-front wave-length
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Página 105 - ... confused, which seems in part owing to want of power in the eye to converge red light. The line B, between red and green, in a certain position of the prism, is perfectly distinct; so also are D and E, the two limits of violet. But C, the limit of green and blue, is not so clearly marked as the rest ; and there are also, on each side of this limit, other distinct dark lines, / and g, either of which, in an imperfect experiment, might be mistaken for the boundary of these colours.
Página 79 - And in order thereto, having darkened my chamber, and made a small hole in my window-shuts, to let in a convenient quantity of the sun's light, I placed my prism at its entrance, that it might be thereby refracted to the opposite wall. It was at first a very pleasing divertisement, to view the vivid and intense colours produced thereby ; but after a while applying myself to consider them more circumspectly, I became surprised to see them in an oblong form, which, according to the received laws of...
Página 78 - I shall without further ceremony acquaint you, that in the beginning of the year 1666 (at which time I applied myself to the grinding of Optic glasses of other figures than Spherical) I procured me a triangular glass-prisme, to try therewith the celebrated Phaenomena of Colours.
Página 82 - The gradual removal of these suspicions at length led me to the experimentum crucis, which was this : I took two boards, and placed one of them close behind the prism at the window, so that the light might pass through a small hole, made in it for the purpose, and fall on the other board, which I placed at about twelve feet distance, having first made a small hole in it also, for some of that incident light to pass through. Then, I placed another prism behind the second board.
Página 183 - I shall endeavour to explain this law by a comparison : — Suppose a number of equal -waves of water to move upon the surface of a stagnant lake, with a certain constant velocity, and to enter a narrow channel leading out of the lake ; suppose, then, another similar cause to have...
Página 79 - Comparing the length of this coloured spectrum with its breadth, I found it about five times greater; a disproportion so extravagant, that it excited me to a more than ordinary curiosity of examining from whence it might proceed.
Página 83 - Prisme in my hand, and turned it to and fro slowly about its Axis, so much as to make the several parts of the Image, cast on the second board, successively pass through the hole in it, that I might observe to what places on the wall the second Prisme would refract them.
Página 16 - Do not all fixed bodies, when heated beyond a certain degree, emit light and shine, and is not this emission performed by the vibrating motions of their parts?
Página 104 - E, the two limits of violet. But C, the limit of green and blue, is not so clearly marked as the rest, and there are also on each side of this limit other distinct dark lines — f and g — either of which, in an imperfect experiment, might be mistaken for the boundary of these colours.
Página 83 - ... through the hole in it, that I might observe to what places on the wall the second prism would refract them. And I saw, by the variation of those places, that the light tending to that end of the image, towards which the refraction of the first prism was made, did in the second prism suffer a refraction considerably greater than the light tending to the other end. And so the true cause of the length of that image was detected to be no other than that light consists of rays differently refrangible,...