Excerpt from Purity and Intensity of Monochromatic Light Sources Many lines are included in the published data of Michelson and Wadsworth which are known to be composite. The author3 has measured the width of lines directly with an echelon provided with a micrometer eyepiece. Corrections for slit width and resolving power were determined experimentally and applied. With the echelon the character of a composite line is at once evident. 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.

Contains results of investigations, researches, etc., pertaining to scientific, technical and manufacturing interests of the country.