Excerpt from A Geological Hand Atlas of the Sixty-Seven Counties of Pennsylvania, Embodying the Results In spite Of the present nearness Of the surface level Of the State to the level of the sea such was not always the case. Our mountains were once ten times higher than they are now and their gradual erosion to their present height by the frosts and rains of past ages, beginning long before the advent of the races Of living beings which now inhabit the planet, makes the most interesting chapter in our geological history. 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.