Excerpt from Spiral and Worm Gearing: A Treatise on the Principles, Dimensions, Calculation and Design of Spiral and Worm Gearing, Together With Chapters on the Methods of Cutting the Teeth in These Types of Gears The manner in which machinery's book, Spur and Bevel Gearing, has been received by the mechanical world has prompted the compilation and publication of a companion book on Spiral and Worm Gearing. This subject has often been presented in so theoretical a manner that many have assumed it to be very difficult to master. It is possible, however, to present the principles of design and calculation of spiral and worm gearing in such a way that they can be readily under stood without resorting to a highly theoretical treatment; and in preparing this book, the first consideration on the part of the editor has therefore been to treat the subject in such'a way as to meet the practical requirementsof the machine-building trade. As a result, in this book, as well as in the companion book, Spur and Bevel Gearing, mere theory and academic discus sions have been avoided. The rules, formulas and instruc tions given are illustrated with engravings whenever necessary, and numerous examples are given to show their application to problems met with in machine design. Theoretical considera tions, however, have not been neglected in cases where they have been found necessary to fully explain a practical process, and this book is, therefore, a treatise on both the theory and practice of spiral and worm gearing along such lines as will make it especially useful to practical men. 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.