Six lectures on light [electronic resource] : delivered in the United States in 1872-1873 (1882)
Tyndall, John, 1820-1893, Parsons, John Herbert, Sir, 1868-1957, donor, University College, London. Library Services, University College, London. Library Services · London : Longmans, Green, and Co. · leaf 38
OX LIGHT. LECT. circle at n. When it is incident along m' E there is also refraction at E, the beam striking the point n'. From the ends of the incident beams, let the perpen- diculars m o, m' o' be drawn upon B D, and from the ends of the refracted beams let the perpendiculars p n, p' n' be also… … the same quotient. Snell, in fact, found this quotient to be a constant quantity for each particular sub- stance, though it varied in amount from substance to substance. He called the quotient the index of refraction. In all cases where the light is incident from air upon the surface of a solid or…
Boyle, Robert, 1627-1691 · Young, Thomas, 1773-1829 · Arago, F. (François), 1786-1853 · Light · Wave theory of light · Optical illusions · Gravitation · Vision
Internet Archive · UCL Library Services, University College London (UCL) · Public domain (published before 1931). Free to use for anything.
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