Book excerpt: Excerpt from The Philosophical Magazine, or Annals of Chemistry, Mathematics, Astronomy, Natural History, and General Science, Vol. 8: July December, 1830 Mr. J. Nixon on the Measurement (by Trigonometry) of the Heights of the principal Hills of Swaledale, Yorkshire (con tinned) 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.