INTRODUCTIONS BY

PROFESSOR E. E. BARNARD, A.M., Sc.D.,
Yerkes Astronomical Observatory.

PROFESSOR CHARLES BASKERVILLE, Ph.D., F.C.S. Professor of Chemistry, College of the City of New York.

DIRECTOR WILLIAM T. HORNADAY, Sc.D.,
President of New York Zoological Society.

PROFESSOR FREDERICK STARR, S.B., S.M., Ph.D.,
Professor of Anthropology, Chicago University.

PROFESSOR CASSIUS J. KEYSER, B.S., A.M., Ph.D., Adrain Professor of Mathematics, Columbia University

EDWARD J. WHEELER, A.M., Litt.D.,
Editor of 'Current Literature.'

PROFESSOR HUGO MÜNSTERBERG, A.B., M.D., Ph.D., LL.D., Professor of Psychology, Harvard University.

01-13-30 H.C.M.

VOL. I-WALDemar KaempfFERT,
'Scientific American.'

VOL. II-HAROLD E. Slade, C.E.

VOL. III-GEORGE Matthew, A.M.

VOL. III-PROFESSOR WILLIAM J. MOORE, M.E., Assistant Professor of Mechanical Engineering, Brooklyn Polytechnic Institute.

VOL. IV-WILLIAM ALLEN HAMOR,

Research Chemist, Chemistry Department, College of the
City of New York.

VOL. V-CAROLINE E. STACKPOLE, A.M.,

Tutor in Biology, Teachers' College, Columbia University.
VOL. VI-WM. D. MATTHEW, A.B., Ph.B., A.M., Ph.D.,
Assistant Curator, Vertebrate Paleontology, American
Museum of Natural History.

VOL. VI-MARION E. LATHAM, A.M.,

Tutor in Botany, Barnard College, Columbia University.
VOL. VII-FRANCIS ROLT-WHEELER, S.T.D.
VOL. VII-THEODORE H. ALLEN, A.M., M.D.
VOL. VIII-L. LELAND LOCKE, A.B., A.M.,
Brooklyn Training School for Teachers.
VOL. VIII-FRANZ BELLINGER, A.M., Ph.D.
VOL. IX-S. J. WOOLF.

VOL. IX-FRANCIS ROLT-WHEELER, S.T.D.
VOL. X-PROFESSOR CHARLES GRAY SHAW, Ph.D.,
Professor of Ethics and Philosophy, New York University.

LEONARD ABBOTT,

Associate Editor 'Current Literature.'