PHILADELPHIA & LONDON

J. B. Lippincott Company

COPYRIGHT, 1915, BY J. B. LIPPINCOTT COMPANY

PRINTED IN UNITED STATES OF AMERICA

To the Memory of

THE LATE

PROFESSOR THOMAS EGLESTON, Ph.D., LL. D.

OFFICIER DE LA LÉGION D’HONNEUR AND FOUNDER OF THE SCHOOL OF MINES, COLUMBIA UNIVERSITY, AN ARDENT LOVER OF MINERALS, KEENLY APPRECIATIVE OF PRECIOUS STONES, AND A KINDLY FRIEND OF THE AUTHOR, THIS VOLUME IS RESPECTFULLY DEDICATED

Preface