Excerpt from Machine Drawing: A Practical Guide to the Standard Methods of Graphical Representation Machines, Including Complete Detail Drawings of a Duplex Pump and of a Direct-Current Generator Lines. The secret of a clear drawing, as far as the line work is concerned, lies not only in absolute uniformity in the making of the lines, but in choosing certain characteristic lines to convey differ ent ideas. The most common kinds of lines used are shown m Fig. 1 and described below, and the purposes of their use are stated. F ull Lines. Full lines represent the portions of the object which are Visible; they should be bold and clear, heavy on detail drawings, say 31 - 2 wide, and lighter on an assembled drawing. 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.