Preston, Thomas, Joly, Charles Jasper, 1864-1906, Parsons, John Herbert, Sir, 1868-1957, donor, University College, London. Library Services · London : Macmillan and Co. · leaf 343
rst lens may be plano-convex and may be cemented to the face of the crystal with Canada balsam. The most convenient method, however, is to stop one of the pencils by total reflection inside the crystal. This is the method adopted in Mcol's prism. A long lozenge-shaped rhomb of calcspar is formed by… … Fig. 159. Nicol's Prism. Fig. 1(50. diagonal BD of the end — that is, perpendicular to the principal plane. The cut faces are then polished and cemented together in their original position by a thin film of Canada balsam. The refractive index of the balsam is greater than that of the extraordinary…
![An illustration from The theory of light [electronic resource], 1901, leaf 343](https://img.insideoutlibrary.com/img/1024/ia-b21286462-343-0.webp)
