Excerpt from Proceedings of the American Academy of Arts and Sciences, Vol. 1 Table I. Light reflected when i: or incident light normal to surface. The light therefore increases with n, being zero when n 1, and 100 per cent, or all reflected when r r: 00. This law also holds for other angles of incidence, and serves to explain many familiar phenomena. The brilliancy of the diamond is mainly due to its high index, causing it to reflect about 20 per cent of the light falling normally on it, while glass returns but 4 per cent. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.