Excerpt from The Graphical Statics of Mechanism: A Guide for the Use of Machinists, Architects, and Engineers and Also a Text-Book for Technical Schools In all these determinations, however, friction and the special hurtful resistances to motion have not been taken into account. Heretofore all attempts to ascertain these hurtful resistances in machines, and' to determine the efficiency which is dependent upon them, and is of such great importance in practice, have been confined to the analytical method, which is often awkward and at times utterly inapplicable. No method is as yet known to me by which the frictional resistances and efficiency of any desired mechanism can be graphically determined. In my lectures on machinery in the polytechnic schools of this place I have endeavored to show the relations existing between the forces in mechanism in a simpler form than that offered by the analytical method. Out of that endeavor has grown the following treatise, which in reality amounts to nothing more than a wider application of the long known but little used angle of friction. 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.