772 REPORT — 1902. 



It seems childish at the present day, and before such an audience as this, to 

 point out how essential it is to know the chemical structure as well as the 

 anatomical structure of the component parts of the body. But the early 

 anatomists to whom I have alluded had no conception of the connection of the 

 two sciences. Speaking of Vesalius, Sir Michael Foster says : ' The great 

 anatomist would no doubt have made use of his bitterest sarcasms had someone 

 assured him that the fantastic school which was busy with occult secrets and 

 had hopes of turning dross into gold would one day join hands in the investiga- 

 tion of the problems of life with the exact and clear anatomy so dear to him.' 

 Nor did Harvey, any more than Vesalius, pay heed to chemical learning. The 

 scientific men of his time ignored and despised the beginning of that chemical 

 knowledge which in later years was to become one of the foundations of physiology 

 and the mainstay of the art of medicine. 



The earliest to recognise this important connection was one whose name is 

 usually associated more with charlatanry than with truth, namely, Paracelsus, and 

 fifty years after the death of that remarkable and curious personality his doctrines 

 were extended and developed by van Helmont. In spite, however, of van Hel- 

 mont's remarkable insight into the processes of digestion and fermentation, his 

 work was marred by the mysticism of the day which called in the aid of super- 

 natural agencies to explain what could not otherwise be fully comprehended. 



In the two hundred and fifty years that have intervened between the death of 

 van Helmont and the present day alchemy became a more and more exact science, 

 and changed its name to chemistry, and a few striking names stand out of men 

 who were able to take the new facts of chemistry and apply them to physiological 

 uses. Of these one may mention Mayow, Lower, Boerhaave, RiSaumur, Borelli, 

 Spallanzani, and Lavoisier. Mulder in Holland and Liebig in Germany bring us 

 almost to the present time, and I think they may be said to share the honour of 

 being regarded as the father of modern chemical physiology. This branch of 

 science was first placed on a firm basis by Wohler when he showed that organic 

 compounds can be built out of their elements in the laboratory, and his first suc- 

 cessful experiments in connection with the comparatively simple substance urea 

 have been followed by numberless others, which have made organic chemistry the 

 vast subject it is to-day. 



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

 alread}^ quoted, treats of the older workers who laid the foundations of our science, 

 and whose names I have not done much more than barely mention. Those inter- 

 ested 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 endeavour that as the older areas yield 

 their secrets to the explorers new ones are opened out which require equally 

 carefid 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, oi even ten years ago. The sister science 

 of chemical pathology is making similar rapid strides. In some universities the 

 importance of biological chemistry is recognised 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 



