en part, generously rendered financial
aid for the Mongolian work.

My wife, who is ever my best assistant in the field, was responsible
for all the photographic work of the expedition and I have drawn
much upon her daily "Journals" in the preparation of this book.

I wish to acknowledge the kindness of the Editors of _Harper's
Magazine_, _Natural History_, _Asia Magazine_ and the _Trans-Pacific
Magazine_ in whose publications parts of this book have already
appeared.

We are indebted to a host of friends who gave assistance to the
expedition and to us personally in the field:

The Wai Chiao Pu (Ministry of Foreign Affairs) freely granted
permits for the expedition to travel throughout China and extended
other courtesies for which I wish to express appreciation on behalf
of the President and Board of Trustees of the American Museum of
Natural History.

In Peking, His Excellency Paul S. Reinsch, formerly American
Minister to China, Dr. C. D. Tenney, Mr. Willys Peck, Mr. Ernest B.
Price and other members of the Legation staff obtained import
permits and attended to many details connected with the Chinese
Government.

Mr. A. M. Guptil acted as our Peking representative while we were in
the field and assumed much annoying detail in forwarding and
receiving shipments of supplies and equipment. Other gentlemen in
Peking who rendered us courtesies in various ways are Commanders I.
V. Gillis and C. T. Hutchins, Dr. George D. Wilder, Dr. J. G.
Anderson and Messrs. H. C. Faxon, E. G. Smith, C. R. Bennett, M. E.
Weatherall and J. Kenrick.

In Kalgan, Mr. Charles L. Coltman arranged for the transportation of
the expedition to Mongolia and not only gratuitously acted as our
agent but was always ready to devote his own time and the use of his
motor cars to further the work of the party.

In Urga, Mr. F. A. Larsen of Anderson, Meyer & Company, was of
invaluable assistance in obtaining horses, carts and other equipment
for the expedition as well as in giving us the benefit of his long
and unique experience in Mongolia.

Mr. E. V. Olufsen of Anderson, Meyer & Company, put himself, his
house, and his servants at our disposal whenever we were in Urga and
aided us in innumerable ways.

Mr. and Mrs. Oscar Mamen often entertained us in their home. Mr. and
Mrs. E. L. MacCallie, who accompanied us on one trip across Mongolia
and later resided temporarily in Urga, brought equipment for us
across Mongolia and entertained us while