Vice-President’s Address. 129 
secretions fail to take from it its power. To me it is a very 
curious fact that brain function—that is, mind—should be so 
dependent upon an organ of this kind, and upon a secretion 
which is as good, for its special purpose, when taken from a 
sheep, as when elaborated in the human body. 
The discovery has necessarily given a place of much higher 
importance to the ductless glands than they formerly held. 
Two other ductless glands may be mentioned—the pituitary 
body, situated inside the skull, and the supra-renal cap- 
sule. I need not dwell on these, as we are not yet fully 
informed of their functions, but everything points to their 
functions being of the utmost importance, although want- 
ing in the special features of interest possessed by the 
thyroid. 
A further result of the study of disease in definite organs, 
and of observations in cases where organs have been removed, 
is to indicate that, in addition to the special activities and 
special functions of organs which have been long known, 
there are side influences, or supplementary functions, which 
play a very subtle réle in the animal economy, and have 
a very marked influence upon brain vigour and mental 
activity, in addition to more palpable physical effects. The 
inference being that, from some of these, substances are 
absorbed which act as invigorators of brain and nerve tissue, 
while others are necessary for the prevention of morbid brain 
action. From these facts, the blood-composition has been 
shown to possess an infinitely more complex character than 
had hitherto been fully realised; and the function of im- 
portant organs and tissues shown to be influenced, and their 
activity determined, by other organs which had no direct or 
apparent connection with them. 
From the foregoing facts you can readily understand that 
quite a new line of investigation has been opened, and that 
the tissue of organs, or extracts of them, have come to be 
regarded as possibly possessing unknown potentialities, which 
might be utilised for various medicinal purposes. It is 
fortunately a line of investigation which can be soon 
exhausted, and the limits of its applicability will soon be 
determined ; and if it were permissible to prophesy, I should 
