Though unknown to me personally, the Rev.Dr.Peter Guilday, of the Catholic University of Washington, consented, with gracious, characteristic urbanity, to read Chapters VI and VIII and a part of Chapter I.

I am grateful to Professor N.S.

B.
Gras, of the University of Minnesota, for reading that part of the book directly concerned with economics (Chapter XI and a part of Chapter X); and to Professor Frederick A.Saunders, of Harvard, for a like service in technical revision of the section on science in Chapter XII.

While acknowledging with hearty thanks the priceless services of these eminent scholars, it is only fair to relieve them of all responsibility for any rash statements that may have escaped their scrutiny, as well as for any conclusions from which they might dissent.
For information about manuscripts and rare books in Europe my thanks are due to my kind friends: Mr.P.S.Allen, Librarian of Merton College, Oxford, the so successful editor of Erasmus's Epistles; and Professor Carrington Lancaster, of Johns Hopkins University.

To several libraries I owe much for the use of books.