E. C. Erdis, E. L. Anderson, Clarence F. Maynard, J. J. Hasbrouck,
Osgood Hardy, Geoffrey W. Morkill, and G. Bruce Gilbert. To these, my
comrades in enterprises which were not always free from discomfort or
danger, I desire to acknowledge most fully my great obligations. In
the following pages they will sometimes recognize their handiwork;
at other times they may wonder why it has been overlooked. Perhaps
in another volume, which is already under way and in which I hope to
cover more particularly Machu Picchu [1] and its vicinity, they will
eventually find much of what cannot be told here.

Sincere and grateful thanks are due also to Mr. Edward S. Harkness for
offering generous assistance when aid was most difficult to secure; to
Mr. Gilbert Grosvenor and the National Geographic Society for liberal
and enthusiastic support; to President Taft of the United States and
President Leguia of Peru for official help of a most important nature;
to Messrs. W. R. Grace & Company and to Mr. William L. Morkill and
Mr. L. S. Blaisdell, of the Peruvian Corporation, for cordial and
untiring coöperation; to Don Cesare Lomellini, Don Pedro Duque,
and their sons, and Mr. Frederic B. Johnson, of Yale University,
for many practical kindnesses; to Mrs. Blanche Peberdy Tompkins and
Miss Mary G. Reynolds for invaluable secretarial aid; and last, but
by no means least, to Mrs. Alfred Mitchell for making possible the
writing of this book.

Hiram Bingham

Yale University
October 1, 1922