I.—PHYSIOLOGY. 131 
engaged in advancing, medical knowledge, and new physiological con- 
ceptions as they took shape in our laboratories only slowly and partially 
came to have effect in medical practice and medical study. The 
physiologist, to his own certain loss and to the no less certain loss of 
_ medicine, held aloof from the bedside, often when access was possible, 
and remained immersed in his laboratory interests. Little pressure, 
_ indeed, was ever brought to bear upon him by the physician to come 
to his aid. Connected with the evils of this separation was the divorce 
which the accidents of development had set up between physiology 
and pathology, as though the study of the damaged body could be 
separated from the science of the living organism and of its reactions 
to any disturbance from the normal. Yet, while the physician had 
come to tojierate the approach of the pathologist to the bedside, it 
occurred too rarely that he felt the need of the physiologist, or made 
himself familiar with new devices of physiological investigation. 
If from a hospital in time of peace the most obvious call had 
seemed in the past to come from the side of infective disease or morbid 
process for the help of the pathologist, in war the stresses put upon 
the healthy human body made the physiologist and his methods indis- 
pensable. Bacteriological work and studies of immunity had their 
prominent place, of course, in the detection and prevention of infective 
disease, and wonderful were many of the achievements seen under 
this head. But in a sense the more complete the prevention of infective 
disease the more apparent became the physical stresses of war. The 
violences offered in modern warfare to the human body—whether 
through exertion and exposure, by terror or excitement, in physical 
damage by lead or steel or in chemical attacks by poison, and not 
least through the incredible stresses of flying high and fighting in the 
air—all these brought many new and urgent calls for precise physio- 
logical knowledge and for new studies by the physiologist. The results 
of pain and fear, of hemorrhage, of ‘ shock’ by wound or operation— 
all these needed further analysis before sound treatment could be 
devised or improved. New studies were needed of changes in blood- 
pressure and blood-volume and in the qualities of the blood itself, new 
inquiries into the finer vessels of blood circulation and their relation 
to the nervous and other systems, and new analyses of the chemical 
mechanisms of the body and of the modes by which want of oxygen 
is met by adaptation or leads to final damage. But the well-nigh 
incredible demands made upon the machinery of man’s body in and 
behind the battle-line, in all situations upon the land or under the earth, 
high in the upper air, in the sea or within its depths, by no means 
make up the tale. Our forces were engaged in every climate, from the 
‘Equator to the Arctic regions, and were faced by innumerable local or 
accidental variations of diet. Here again were required the applications 
of physiological studies of heat loss and of heat production to manifold 
practical problems of clothing and of diet. What would have seemed a 
fanciful fairy tale barely twenty years ago might in particular be told 
of the miracles wrought by the studied application of our new knowledge 
of ‘vitamins’ in diet, in saving from painful disease or death many 
thousands of men in diverse climates and fields of war, 
