Copyright © 1998 by Princeton University Press

Published by Princeton University Press, 41 William Street,

Princeton, New Jersey 08540

In the United Kingdom: Princeton University Press, 6 Oxford Street,

Woodstock, Oxfordshire OX20 1TW

press.princeton.edu

Cover art © Eugen Jost, Switzerland

All Rights Reserved

First printing, 1998

Sixth printing, and first paperback printing, 2002

Paperback reissue, for the Princeton Science Library series, 2013

Library of Congress Control Number 2012950191

ISBN 978-0-691-15820-4

British Library Cataloging-in-Publication Data is available

This book has been composed in Times Roman

Printed on acid-free paper. ∞

Printed in the United States of America

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