organization set up by France, and its violent disruption by the revolt
of the American colonies. In all these four periods the dominant
motive is economic. The fifth period, in which we ourselves live, is
altogether different. It is a recommencement on new lines, having
no precedent in the history of modern nations. In its essence it is
the record of an overflow of population much more voluminous and
much less under the guidance of a national policy than ever before,
and its principal interest is not economic but social and political. Also
it is not, like the other periods, a finished tale. It breaks off in the midst
of a chapter, and the outcome is for the future to reveal.

Such is the scope of the subject. To unfold it entails working some-
times from the centre, to obtain a proportioned view and to deal with
ideas and policy, and sometimes in compartments, to trace the history
of various undertakings. The method involves some repetition, but
its advantages appear to counterbalance its defects.

Footnote references to authorities are inserted where the facts stated
are disputable or of recent discovery, and also to acknowledge the
source of quotations, and sometimes to indicate generally the authority
followed. The lists of works at the end of each part are not exhaustive.
They aim rather at suggesting courses of reading and indicating the
particular uses of the books mentioned. They omit many older works
whose authority is good, but whose substance is included in more
recent writings.

THE re-writing and enlargement of that part of the book which deals
with British expansion after 1783 has necessitated the issue of the
second edition in the form of two volumes. The present volume
therefore contains Parts I-IV and treats of the history of the Old
Colonial Empire. Certain corrections, particularly in the account of
the West Indian colonies in the seventeenth century, have been made
in accordance with the results of recent research. These corrections
were first introduced in the reprint of the first edition in 1927.

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