THE BIRTH AND GROWTH OF SCIENCE IN MEDICINE. 2 1 



sciences medicine is perhaps the most complex, the most 

 dependent upon other sciences for its development. 

 Hence it is from outside medicine that the chief stimuli 

 to progress in medical science have come. In saying this 

 I would not be thought to undervalue the vast internal 

 progress which has been brought about by clinical study. 

 One has but to recall the mighty name of Sydenham to 

 realise what a pure clinician can accomplish. Sydenham 

 would have none of physiology or pathology, and we may 

 almost wonder whether one so disdainful of science would 

 have been pleased to know that he was the founder of 

 Epidemiology. 



There is room for difference of opinion as to the impulses 

 from external sources which have had the most far- 

 reaching effects upon medicine, but I would name four 

 as of exceptional importance. They are : the invention of 

 the compound microscope, the development of chemistry, 

 the acceptance of the doctrine of evolution, and the dis- 

 covery of the relation of micro-organisms to disease. 



The microscope was invented in Holland early in the 

 seventeenth century, but its possibilities as an aid to 

 anatomy were not at first grasped, and it was not till after 

 Harvey's death that Malpighi actually saw the capillaries, 

 and the contrary direction of the blood-flow in arteries 

 and veins. The rise of histology from that time forward 

 has transformed our ideas of the structure of the body, 

 and with each improvement in the microscope our hori;?on 

 has widened. We have passed from the organ to the 

 units of which it is built up, and Virchow's ' Cellular 

 Pathology ' marks an epoch in the history of medicine. 

 To-day we are a stage further, for the inquiry is being 

 pushed into the more intimate structure of the cell itself, 

 in the hope of revealing the nature of the processes by 

 which it carries on its work. 



The rise of physics and chemistry has been even more 

 fruitful for medicine. We cannot nowadays consider them 

 separately, so closely merged have they become. We 

 recognise the fundamental importance of these sciences 



