Excerpt from Electrical Equipments for Movable Bridges Nearly all railroad bridges are built without interrup tion of traffic, and even put into commission with only a few hours' delay. Each individual bridge embodies many new and un tried conditions, which must be met successfully with few chances for preliminary experiments. Such a schedule requires a type of engineering, which is seldom required in other branches of work where repeated duplication overcomes faults as they appear in earlier attempts. 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.