v INTRODUCTION 
consistent with the truths of economic science. Thus the 
first part of this book comprises an historical account of 
monetary systems and of their operation. In the second 
and third parts an attempt will be made to deduce the 
theoretical conclusions and to work out some of their 
implications in practice. 
AUTHOR’S NOTE 
Tue work of which this is the English translation 
appeared in French in the middle of 1924. Certain 
events have occurred since that date; some countries 
have emerged from the monetary crisis, and Great 
Britain, in particular, has completely re-established 
exchange stability. 
The reader is asked to remember this remark in 
reading the following chapters. It may be added, how- 
ever, not only that the theoretical part of the book 
needs no change, but that the results which have been 
obtained since it appeared are entirely in harmony with 
the author’s previous observations and with his practical 
conclusions; the restoration of the currency in Great 
Britain, and particularly in Belgium, has been carried 
out in strict conformity with the plan which he has 
sketched. 
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