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Excerpt from Vertical Cross Sections of the Ionosphere Across the Geomagnetic Equator The National Aeronautics and Space Administration has supported at the National Bureau of Standards, a substantial program concerned with the determination of height profiles of electron density using ionospheric vertical soundings, with a special View toward the pro vision of ionospheric data essential to various scientific and practical aspects of space programs. As a pilot study, the nbs has undertaken an intensive analysis of ionograms from the chain of stations located along the 750w meridian from Washington, D. C. To Concepcion. 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.