domain of PATHOLOGICAL ANATOMY, we find
the same elements in morbid growths that we have met with in normal
structures. The pus-corpuscle and the white blood-corpuscle can only
be distinguished by tracing them to their origin. A frequent form of
so-called malignant disease proves to be only a collection of altered
epithelium-cells. Even cancer itself has no specific anatomical element,
and the diagnosis of a cancerous tumor by the microscope, though
tolerably sure under the eye of an expert, is based upon accidental, and
not essential points,--the crowding together of the elements, the size
of the cell-nuclei, and similar variable characters.

Let us turn to PHYSIOLOGY. The microscope, which has made a new science
of the intimate structure of the organs, has at the same time cleared up
many uncertainties concerning the mechanism of the special functions. Up
to the time of the living generation of observers, Nature had kept over
all her inner workshops the forbidding inscription, No Admittance! If
any prying observer ventured to spy through his magnifying tubes into
the mysteries of her glands and canals and fluids, she covered up her
work in blinding mists and bewildering halos, as the deities of old
concealed their favored heroes in the moment of danger.

Science has at length sifted the turbid light of her lenses, and
blanched their delusive rainbows.

Anatomy studies the organism in space. Physiology studies it also in
time. After the study of form and composition follows close that of
action, and this leads us along back to the first moment of the germ,
and forward to the resolution of the living frame into its lifeless
elements. In this way Anatomy, or rather that branch of it which we call
Histology, has become inseparably blended with the study of function.
The connection between the science of life and that of intimate
structure on the one hand, and composition on the other, is illustrated
in the titles of two recent works of remarkable excellence,--"the
Physiological Anatomy" of Todd and Bowman, and the "Physiological
Chemistry" of Lehmann.

Let me briefly recapitulate a few of our acquisitions in Physiology, due
in large measure to our new instruments and methods of research, and
at the same time indicate the limits which form the permanent or the
temporary boundaries of our knowledge. I will begin with the largest
fact and with the most absolute and universally encountered limitation.

The "largest trut