RESOURCES FOR THE FUTURE, INC.
1755 Massachusetts Avenue, N.W., Washington, D.C. 20036

Board of Directors:
Erwin D. Canham, Chairman, Robert O. Anderson, Harrison Brown, Edward J.
Cleary, Joseph L. Fisher, Luther H. Foster, F. Kenneth Hare, Charles J. Hitch,
Charles F. Luce, Frank Pace, Jr., Emanuel R. Piore, Stanley H. Ruttenberg, Lauren
K. Soth, Maurice F. Strong, Mrs. Robert J. Stuart, P. F. Watzek, Gilbert F. White.
Honorary Directors: Horace M. Albright, Reuben G. Gustavson, Hugh L. Keenley-
side, Edward S. Mason, William S. Paley, Laurance S. Rockefeller, John W. Vander-
wilt.

President: Joseph L. Fisher
Secretary-Treasurer: John E. Herbert

Resources for the Future is a nonprofit corporation for research and education in the
development, conservation, and use of natural resources and the improvement of the
quality of the environment. It was established in 1952 with the cooperation of the
Ford Foundation. Part of the work of Resources for the Future is carried out by its
resident staff; part is supported by grants to universities and other nonprofit organiza-
tions. Unless otherwise stated, interpretations and conclusions in RFF publications
are those of the authors; the organization takes responsibility for the selection of
significant subjects for study, the competence of the researchers, and their freedom of
inquiry.

These papers are part of the RFF natural environments program, which is directed
by John V. Krutilla.

RFF editors: Mark Reinsberg, Vera W. Dodds, Nora E. Roots, Tadd Fisher.

Copyright © 1972 by Resources for the Future, Inc.
All rights reserved
Manufactured in the United States of America

The Johns Hopkins University Press, Baltimore, Maryland 21218
The Johns Hopkins University Press Ltd., London

Library of Congress Catalog Card Number 72-4441
ISBN 0-8018-1446-4

Library of Congress Cataloging in Publication data will
be found on the last printed page of this book.

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