This Dover edition, first published in 1954, is an unabridged and
unaltered republication of the English translation originally published
by Macmillan and Company, Ltd., in 1921. This edition is published by
special arrangement with Macmillan and Company, Ltd.
The publisher is grateful to the Library of the University of
Pennsylvania for supplying a copy of this work for the purpose of
reproduction.
_Standard Book Number: 486-20257-7 Library of Congress Catalog Card
Number: 54-4730_
Manufactured in the United States of America
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