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"Thus, when erher waves that constitute light are transmitted through glass, they are hindered by the molecules of the glass, and impart some of their motion to those molecules' i.e., a part of the light is absorbed. When a beam of light, as represented by ABC moves forward in the air, the wave-front, MN, continues parallel to itself and moves forward in a straight line. As the wave front advances, A strikes the glass first, and is retarted, the retardation of B and C later change the direction of the rays." -Avery 1895

Explanation of Refraction

"Thus, when erher waves that constitute light are transmitted through glass, they are hindered by the…