152 SECTIONAL ADDRESSES. 



diabetes ; from that time onwards it was evident that if the missing 

 pancreatic function could be replaced a cure would be possible, and it was 

 justifiable deliberately to search for some means of doing this. But the 

 search was in vain until another new idea came into physiology by reason 

 of the discovery of the existence of autacoids. From this point on all 

 was clear in theory, and it is no detraction from the merit of subsequent 

 work to say that the final happy result depended principally upon 

 inventive technique and manipulative skill, and only in a lesser degree 

 upon discovery. 



Discoveries are infrequent, in a sense fortuitous, and often dependent 

 on rare qualities of intellect as well as on accurate observations, and they 

 mostly come out of the fullness of time. 



We all feel great pride in recalling that one of the greatest of all dis- 

 coveries, which has recently been celebrated at the tercentenary of the 

 publication of William Harvey's famous book " de motu cordis," was made 

 in our own country. Here was a genuine revelation that put old facts in 

 a new light. It is of interest to reflect that the hospital at which Harvey 

 was a physician had been carrying on its work as such for over 500 years 

 at the time his discovery was made. What fundamental changes in the 

 outlook of the physician and surgeon has that hospital seen during the 

 ensuing 300 years in consequence of his revelation ! And what further 

 mutations in thought and practice will it have witnessed when Harvey 

 stands as a beacon half-way in its eventful history ? For we are privileged 

 to live in times pregnant with opportunity for the science of medicine. 



Incidentally it has been claimed, with more audacity than insight, that 

 experiments upon living animals serve no useful purpose, and it has even 

 been pretended that Harvey had no need for such experiments in the 

 classical researches which formed the foundations of physiology and gave 

 reason to physic. Yet we have Harvey's own words. . . . ' At length, 

 and by using greater and daily diligence, having frequent recourse to 

 vivisections, employing a variety of animals for the purpose, and collating 

 numerous observations, I thought that I had attained to the truth, that 

 I should extricate myself and escape from this labyrinth, and that I had 

 discovered what I so much desired, both the motion and the use of the 

 heart and arteries.' 



The experimental method, which was revived by Harvey, now forms 

 the permanent basis of physiological as of medical knowledge, and in 

 spite of all criticisms must obviously remain so. Riolan, in advancing 

 against Harvey the criticism that ' it is a mockery to attempt to show the 

 circulation in man by the study of brutes,' was, as Gley has recently 

 remarked, ' already employing the argument, if it can be called one, 

 which is encountered under the pen of the antivivisectionists of all times, 

 and which illustrates the diuturnity of ignorance and folly.' 



Let anyone with sufficient acquaintance with physiology try to write 

 an account of such of the main facts concerning the functions of the 

 heart and of the circulation as are most valuable in medicine, without 

 reference to any fact obtained directly or indirectly by animal experimenta- 

 tion, and he will find his essay a very sorry one indeed : for no doctor can 

 use a stethoscope, feel a pulse, take a blood-pressure, administer a 

 hypodermic, give an anaesthetic or a transfusion, perform any modern 



