128 SECTIONAL ADDRESSES. 
knowledge by experiment. The second has been the supply of living 
necessities through the ancient endowments of the colleges, and these 
in the Cambridge of the last half-century have been freely and increas- 
ingly used in catholic spirit for the increase of any of the borders of 
knowledge. 
If these have been the chief lines of descent along which our present 
heritage has come to us, as mind has influenced mind and the light 
has been passed from hand to hand, what has been the outcome as 
we look back over the half-century to those small beginnings? 
Truly we can say that the workers in this country have in that 
short space of years laid the whole world under a heavy debt. In 
whatever direction we look we seem to see that in nearly all the great 
primary fields of physiological knowledge the root ideas from which 
further growth is now springing are in great part British in origin, 
and based upon the work of British experimenters. If we consider 
the blood circulation we find that our essential ideas of the nature of 
the heart-beat were established by Gaskell, and that other first prin- 
ciples of its dynamics and of its regulation have been laid down by 
successors to him still with us; that the intricate nervous regulation of 
the arterial system has had its chief analyses here, and that here 
have been made more recently the first demonstrations of the part 
played by the minute capillary vessels in the regulation of the distribu- 
tion and composition of the blood. Of the central nervous system 
the modern conceptions of function in terms of the purposive integration 
of diverse impulses along determined paths have sprung direct from 
British work, while the elementary analysis of the structure and 
functions of the sympathetic nervous system has been almost wholly 
British in idea and in detail. As with the nervous regulation of the 
body, so with the chemical regulation of function by travelling sub- 
stances—the so-called ‘ hormones,’ or stimulants from organ to organ— 
this, too, is a British conception enriched by numerous examples drawn 
from experimental work in this country. In the study of nutrition, 
of the primary ‘ foodstuffs,’ proteins, carbohydrates, fats, salts, and 
water, whose names in their supposedly secure sufficiency were written 
with his own hand by Foster upon the blackboard shown in his portrait 
by Mr. John Collier, to typify, as we may imagine, a basal physio- 
logical truth, we have come to learn that these alone are not sufficient 
for growth and life in the absence of minimal amounts of accessory 
unknown and unstable substances, the so-called ‘ vitamins,’ which are 
derived from pre-existent living matter. This conception, undreamt of 
to the end of the nineteenth century, has fundamental value in medicine 
and in agriculture, and has already begun to bear a harvest of practical 
fruit of which the end cannot be seen or the beneficence measured. This 
discovery stands to our national credit, and large parts of its develop- 
ment and application have been due to recent British work. If we 
turn to the regulation of respiration and its close adaptation to body 
needs, that also, as it is now known to the world, is known as British 
labours have revealed it, just as the finer analyses of the exchanges 
of gas between the air and the blood and between the blood and the 
body substance have been made with us. The actual modes by which 
