PREFACE THE present volume consists in great measure of selections from the matter contained in a larger treatise1 on the same subject, of which it may therefore in a certain sense be described as an abridged edition. The portions selected have, however, been completely rearranged and rewritten in fuller detail with much additional illustration, and the whole consequently forms a virtually new book, which, being smaller in compass and more elementary in character, may, it is hoped, serve as an introduction to the larger work, and meet the wants of junior students of engineering and others commencing the study of the subject. The want of a book of this class having been felt for use at the engineer school at Keyham and elsewhere, the writer considered with some care the most suitable plan of arrangement, the method of treatment, and the 1 Applied Mechanics, by James H. Cotterill, F.R.S., Professor of Applied Mechanics in the Royal Naval College, Greenwich. 557667 additional matter required. Subsequently, his time and attention being fully occupied with other work, the task of preparing the present treatise was entrusted to his friend and (late) assistant, Mr. J. H. Slade, who undertook to provide both text and examples, in accordance with the original plan. The examples, over 250 in number, have with few exceptions been constructed especially for this book, and it is hoped will be found to add considerably to its utility. GREENWICH, November 1890. CONTENTS PAGE Part E Screw Motion. Cutting a Screw, Double Threads. Examples of Screws EFFORTS AND RESISTANCES-FRICTION Sources of Efforts and Resistances. Elastic Fluids. Gravi- Representation Work in Sliding. Unit of Work. Energy. Principle |