Acknowledgment.


To have prepared this book within the time allotted to it, without the
assistance of Candidates ALCOTT FARRAR ELWELL and LYLE MILTON PROUSE
would have been impossible, and grateful recognition is made of their
services. Not only much of the manual labor, but the preparation of
entire chapters, has been in their hands.

Candidates CHARLES HUNTINGTON JACOBS and MICHAEL FRANCIS MCALEER have
rendered very valuable assistance and we wish to thank the following
candidates for the loan of materials used elsewhere, for typewriting
and other work:

GLENN MACK AINSWORTH.
PHILIP M. BROWN.
NELSON P. BUMP.
EDWIN G. BURROWS.
PHILIP DOREMUS.
WALTER LANE HARDENBROOK.
ALBERT BLANCHARD KELLOGG.
HENRY PRATT MCKEAN.
LOREN RAY PIERCE.
HARRY RAPHAEL SAFTEL.
ROLAND EMERY PACKARD.
HOYT SHERMAN.