138 SECTIONAL ADDRESSES, 
while an exactly similar dose of duck egg-albumin will produce no effect 
whatever; and so vice versa. Here, then, is some authentic stamp 
of unknown kind imposed uniformly upon the parts of the organism 
of a given species, even upon the molecules of the albuminous coating 
of its egg. We are brought sharply back from the relative simplicities 
of chemical analysis to consider this supra-chemical impress of specific 
pattern, a phenomenon which can have no meaning that is not drawn 
from a conception of the organism as a whole. 
It would be impossible here, and quite unnecessary for the present 
purpose, to do more than refer finally to the beautiful researches of 
recent years upon the modes of regulation of breathing, upon the gas 
exchanges of the blood, and upon the associated activities of other 
organs, and especially of the kidney, which have brought such ample 
support and illustration to the doctrine first clearly taught by Claude 
Bernard, namely, that the different mechanisms of the body, various 
as they are, have their single object in ‘ preserving constant the condi- 
tions of life in the internal environment.’ These regulative functions 
in particular have been fully discussed by Dr. Haldane in a recent 
notable essay, and he has shown how, as their chemical analysis has 
proceeded and observations have been collected by physiological 
methods, themselves of a delicacy often far exceding present 
physical and chemical methods, it has become more and more necessary 
to express the facts in terms of an organic unity. ‘The physical and 
chemical picture is entirely obliterated by the picture of organism.’ 
These considerations are full of interest, of course, in their relation to 
the rival mechanistic and vitalistic theories that have been advanced 
for the explanation of living processes. Here, however, I refer to this 
synthetic tendency of modern physiology because of its practical bearing 
upon the present development of the subject in the universities and 
the medical schools. As the preliminary analyses of the functions have 
been, as we have seen, centrifugal and fissiparous in their tendencies, 
so the accompanying and inevitable synthesis, resuming analytical data 
within the notion of organism, has been centripetal and conjugative. 
It is this bond of organic unity which must sooner or later serve to bring 
together the scattered workers in different fields of analysis. It is this 
conception of the organism, moreover, which must maintain physiology 
as a great primary branch of study—the study of the living organism. 
If physiology remains as a free subject of university study, we need 
not have serious fear that the fissiparous, centrifugal tendencies 
already noticed will be dangerous or crippling. Ludwig organised his 
physiology teaching at Leipzig in 1846 under the three main divisions 
of histology, experimental work, and physiological chemistry. In the 
English revival that we have earlier sketched, this grouping, largely 
under the influence of Foster, was maintained not only at Cambridge, 
but at other centres here and in America. As years have passed, how- 
ever, there has been an increasing tendency here to follow what is 
commonly done in other countries, and to place histology with anatomy, | 
In my personal view, physiology cannot proceed without perpetual use 
of the microscope, and yet anatomy must be dead without histology. I 
should hope to see histology the well-worn bridge of union between the 
