Excerpt from An Experimental Treatise on Optics: Comprehending the Leading Principles of the Science, and an Explanation of the More Important and Curious Optical Instruments and Optical Phenomena; Being the Third Part of a Course of Natural Philosophy He first examined, as also Dr Brewster did, the effects of certain coloured glasses in almost obliterating certain coloured spaces in the spectrum, whilst others were transmitted in all their brilliancy. This fact was noticed by Dr Young. Mr Herschel, in applying to the examination of it the uncommon powers of his analytical skill, has resolved the phenomena into their most general expression, and thus traced the causes of many interesting consequences which otherwise would not have been deduced. 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.