Excerpt from The Annual of Scientific Discovery: Or, Year-Book of Facts in Science and Art, for 1871, Exhibiting the Most Important Discoveries and Improvements in Mechanics, Useful Arts, Natural Philosophy, Chemistry, Astronomy, Geology, Biology, Botany, Mineralogy, Meteorology, Geography, Antiquites We can point with pride to some substantial engineering work of the past year: notably, the building, launching, and placing the great caisson at the Brooklyn terminus of the East River bridge. An extract from the report of Col. Roebling will be found in the present volume. It is stated that the great central shaft of the Hoosac Tunnel has reached the grade of the tunnel feet below the natural surface. The Broadway Underground Railway is well underway; the construction progressing while the thoroughfare above is crowded With its endless procession of vehicles. 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.