PART I

DOVER PUBLICATIONS, INC. NEW YORK

Published in Canada by General Publishing Company, Ltd., 30 Lesmill Road, Don Mills, Toronto, Ontario.

Published in the United Kingdom by Constable and Company, Ltd., 10 Orange Street, London WC 2.

This Dover edition, first published in 1962, is an unabridged and unaltered republication of the work originally published by the United States Government Printing Office. Part I was originally published in 1927 as Smithsonian Institution United States National Museum _Bulletin 142_;