An introduction to the science & practice of photography (1891)
Jones, H. Chapman (Henry Chapman), 1854- · London : Iliffe & Son · leaf 89
REFRACTION OF LIGHT — LENSES. 83 the boundaries of the surfaces until they meet. It should be noted, however, that if an object is viewed directly through a dense medium with non-parallel sides, the apparent displacement of the object is towards the thinner part of the interposed substance, because… … Fig. 10. shown, and the apparent displacement of an object viewed directly is indicated by the broken lines. If two prisms are placed base to base, light passing through them is concentrated, while if they are placed apex to apex the light is caused to diverge (figure n). If Fig. 11. these two…
Photography
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