Copyright © 2012
by
The Goodheart-Willcox Company, Inc.
Previous editions copyright 2008, 2004, 2000, 1996, 1993, 1991
All rights reserved. No part of this work may be reproduced, stored, or
transmitted in any form or by any electronic or mechanical means, including
information storage and retrieval systems, without the prior written permission
of The Goodheart-Willcox Company, Inc.
Manufactured in the United States of America
Library of Congress Catalog Card Number 2010032868
ISBN 978-1-60525-428-9
2 3 4 5 6 7 8 9 – 12 – 16 15 14 13
The Goodheart-Willcox Company, Inc. Brand Disclaimer: Brand names, company names, and illustrations for products
and services included in this text are provided for educational purposes only and do not represent or imply endorsement
or recommendation by the author or the publisher.
The Goodheart-Willcox Company, Inc. Safety Notice: The reader is expressly advised to carefully read, understand,
and apply all safety precautions and warnings described in this book or that might also be indicated in undertaking the
activities and exercises described herein to minimize risk of personal injury or injury to others. Common sense and good
judgment should also be exercised and applied to help avoid all potential hazards. The reader should always refer to the
appropriate manufacturer’s technical information, directions, and recommendations; then proceed with care to follow
specifi c equipment operating instructions. The reader should understand these notices and cautions are not exhaustive.
The publisher makes no warranty or representation whatsoever, either expressed or implied, including but not limited to
equipment, procedures, and applications described or referred to herein, their quality, performance, merchantability, or
fi tness for a particular purpose. The publisher assumes no responsibility for any changes, errors, or omissions in this book.
The publisher specifi cally disclaims any liability whatsoever, including any direct, indirect, incidental, consequential,
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Cover Source: Shutterstock (rf)
Library of Congress Cataloging-in-Publication Data
Gradwell, John B.
Technology : engineering our world / by John B. Gradwell, Malcolm Welch. -- 7th ed.
p. cm.
Rev. ed. of Technology : shaping our world / John B. Gradwell, Malcolm Welch,
Eugene Martin. 2004.
Includes index.
ISBN 978-1-60525-428-9
1. Technology. 2. Engineering. I. Welch, Malcolm. II. Title.
T47.G69 2012
600—dc22
2