THANKS ARE EXTENDED here to all who enriched a
fleeting hour while unawares they influenced the form of this
investigation.

The author owes particular appreciation to

Mr. Herman Liebaers, Conservateur en chef, Bibliothèque
Royale de Belgique, in Brussels; to Mr. E. Clark Stillman,
Secretary of the Belgian American Educational Foundation,
Inc., and generally to all those connected with the C. R. B.
Grant that made possible a part of this writing;

to two colleagues,

Professors Edward J. Geary and Edward P. Morris, both of
Harvard University, for assistance beyond the call of pleasure
in the hunt for those devils that subvert syllogisms, factual ref-
erences, and the printed page;

and to two teachers,

Professor Justin O'Brien, of Columbia University, especially
for his learned and patient work with the text; and

Professor Nathan Edelman, of the Johns Hopkins Univer-
sity, especially for his wise and patient work with the author.

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