(BQ) Beginning with the simplest of machines — the lever — the text proceeds to discussions of the block and tackle (pulleys and hoists), wheel and axle, the inclined plane and the wedge, the screw, and different types of gears (simple, spur, bevel, herringbone, spiral, worm, etc.). A chapter on the concept of work discusses the measurement of work, friction, and efficiency; this is followed by investigations of power, force, and pressure, with explanations of the uses of scales, balances, gauges, and barometers. The fundamentals of hydrostatic and hydraulic machines (such as the hydraulic braking system and the hydraulic press) are discussed in detail. | BASIC MACHINES AND HOW THEY’ WORK Prepared Naval Dover by Bureau of Personnel Publications, New York Inc. Published in Canada by Gemml Publishing Company, Ltd., 30 Lesmill Road, Don Mills, Toronto, Ontario. Published in the United Kingdom by Constable and Company, Ltd., 10 Orange Street, London WC 2. This Dover edition, lint published in 1971, is an ilnabridged and unaltered republication of the work originally published by the United States Government Printing Office in 1965, under the title: Basic Machines. This work was prepared by the Bureau of Naval Personnel, Department of the Navy, as Navy Training Course NAVPERS . t*.imaiiwzoi Standard Book Number: O-486-21709-4 Library of Congress Catalog Cord Number: Manufactured in the Uniti States of America Dover Publications, Inc. 180 vatick street New Yodi, N. Y. 10014 PREFACE Basic Machines is written as a reference far the enlisted men in the Navy whose duties require knowledge of the fundamentals of machinery. Beginning with the sim&_t .,i machines-the lever-the book proceeds with tiie discussicn of block and tackle, w!xel and axle, inclined plane, screw and gears. It explains the concepts of work and #aver, and differentiates between the terms “force” and “pressure, ” The fundamentals of hydznstatic and hydraulic mechanisms are discussed in detail. The final chapters include several examples of the combination of simple mechanisms to make complex machines. As one of several basic Navy Training Courses, this book was p-pared by the Education and Training Support Service, Washington, D. C., far the Chief of Naval Personnel. CONTENTS Page CHAPTER 1 1. Levers . 2. Block and Tackle 3. The Wheel and Axle 4. The Inclined Plane and Wedge. 23 5. The Screw 26 6. c&i-s. 7. Work . 39 8. -r,.wr 46 9. Force afid .
