CHEMICAL PHYSIOLOGY. 29 



Sir Michael Foster's book on the History of Physiology, from which 

 I have already quoted, treats of the older workers who laid the founda- 

 tions of our science, and whose names I have not done much more than 

 barely mention. Those interested in the giants of the past should 

 consult it. But what I propose to take up this morning is the work 

 of those who have during more recent days been engaged in the later 

 stages of the building. The edifice is far from completion even now. 

 It is one of the charms of physiological endeavor that as the older areas 

 yield their secrets to the explorers new ones are opened out which 

 require equally careful investigation. 



If even a superficial survey of modern physiological literature is 

 taken, one is at once struck with the great preponderance of papers and 

 books which have a chemical bearing. In this the physiological journals 

 of to-day contrast very markedly with those of thirty, twenty or even 

 ten years ago. The sister science of chemical pathology is making similar 

 rapid strides. In some universities the importance of biological 

 chemistry is recognized by the foundation of chairs which deal with 

 that subject alone; and though in the United Kingdom, owing mainly 

 to lack of funds, this aspect of the advance of science is not very 

 evident, there are signs that the date cannot be far distant when every 

 well-equipped university or university college will follow the example 

 set us at many seats of learning on the continent and at Liverpool. 



With these introductory remarks let me now proceed to describe 

 what appear to me to be the main features of chemical physiology at 

 the present time. 



The first point to which I shall direct your attention is the rapid 

 way in which chemical physiology is becoming an exact science. 

 Though it is less than twenty years since I began to teach physiology, 

 I can remember perfectly well a time when those who devoted their 

 work to the chemical side of the science might almost be counted on 

 the fingers of one hand, and when chemists looked with scarcely veiled 

 contempt on what was at that time called physiological chemistry : they 

 stated that physiologists dealt with messes or impure materials, and 

 therefore anything in the nature of correct knowledge was not possible. 

 There was a good deal of truth in these statements, and if physiologists 

 to-day cannot quite say that they have changed all that, they can at 

 any rate assert with truth that they are changing it. This is due to a 

 growing rapprochement between chemists and physiologists. Many of 

 our younger physiologists now go through a thorough preliminary 

 chemical training; and, on the other hand, there is a growing number 

 of chemists of whom Emil Fischer may be taken as a type who are 

 beginning to recognize the importance of a systematic study of sub- 

 stances of physiological interest. A very striking instance of this is 

 seen in the progress of our knowledge of the carbohydrates, which has 



