BY ISAAC HAYS, M. D.,

EDITOR OF THE AMERICAN JOURNAL OF T DISCARDED BY

BOSTON MEDICAL LIBRARY

IN THE

FRANCIS A. COUNTWAY
LIBRARY OF MEDICINE

Entered, according to the Act of Congress, in the year 1855, by

BLANCHARD & LEA,

in the Clerk's Office of the District Court of the United States for the Eastern
District of Pennsylvania.

то

MARSHALL HALL, M. D. F.R.S., &c.,

THIS LITTLE WORK,

UNDERTAKEN AT HIS SUGGESTION,

AND

PROMOTED BY HIS ASSISTANCE,

Es Enscribed by

THE AUTHOR.