Excerpt from Atlas of the Engravings to Illustrate and Practically Explain: The Construction of Roofs of Iron, Intended to Further Elucidate This Particular Mode of Building With Iron for Public Edifices The weight of the Western Railway roof, including the boarding, frames, corrugated iron covering, gutters, ventilating irons, but without including the columns, was about 125} lb. Per yard superficial. The strain supposed to be brought upon the trusses was estimated at the rate of about 91; lb. Per yard superficial, in addition to the weight of the roof itself. As the Western Railway had been opened for traffic some time previously to the execution of this roof, some ingenuity was required in its erection whilst the ordinary movement of passenger traffic was being carried on this object was effected by raising the entire principals from a staging which covered the respective lines of rails. 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.