1876.] 



Presidents Address, 



357 



kind were being carried on, put an end to these narrow conceptions. It 

 was felt at once that a new path of inquiry had been opened up for the 

 study, not only of hepatic, but of all other tissues — a path of which even 

 yet we see only the beginning. 



Though such theoretical considerations as the foregoing stamp the dis- 

 covery of glycogen as emphatically epoch-making in the history of phy- 

 siology, its immediate and practical fruits were not inconsiderable. It 

 and the subsequent discovery by Bernard that puncture of the fourth ven- 

 tricle produces a temporary artificial diabetes, at once threw a vivid light 

 over the dark subject of diabetic disease ; and if neither the labours of 

 Bernard himself nor those of Pavy and others, who have extended and, 

 in a measure, corrected Bernard's conclusions, have cleared up the whole 

 mystery of this fatal malady, its rational pathology began v>ith the dis- 

 covery of glycogen ; and the complete interpretation of it, when it comes, 

 must be based on Bernard's results. 



No less epoch-making than the discovery of glycogen was the obser- 

 vation made by Bernard in the early months of 1852, that division of the 

 cervical sympathetic caused a dilatation of the blood-vessels of the face 

 and neck. That simple experiment was the beginning of the long series 

 of researches on vaso-motor nerves, on nerves of secretion, we may 

 perhaps add nerves of nutrition, and on inflammation, which so eminently 

 characterize the physiology of the present generation. The progress of 

 physiology during the last twenty years has been far more rapid with 

 respect to our knowledge of the laws regulating vascular supply and 

 secretion than in any other direction. Kor is the value of Bernard's 

 initial experiment lessened by the fact that in a later month (August) of 

 the same year, Brown- Sequard had independently obtained similar 

 results to those of Bernard, and had pushed them further than he had, 

 nor by the fact that Waller in the same year had seen the importance of 

 the new truth more clearly than Bernard himself seems at first to have 

 done. The air of physiology was at that time heavy with some such 

 discovery ; and since Bernard not only was the first to call attention to 

 the facts, but also subsequently expounded fully their importance, his 

 merit in the discovery cannot be diminished by others having indepen- 

 dently arrived at the same results. 



But Bernard's merits as a physiologist do not end here. Second only 

 in importance to the discovery of glycogen and vaso-motor nerves was 

 the observation made by him in 1856, and at about the same time inde- 

 pendently by Kolliker, that the South- American arrow-poison, urari, 

 destroys the conductivity and irritability of motor nerve- endings, but 

 leaves muscular contractility intact. This was of great theoretical im- 

 portance, inasmuch as it afforded striking evidence in support of Haller's 

 views on muscular contractility, views \^hich had been somewhat 

 thrown into the background; and though the opinions expressed by 

 Bernard in publishing this important discovery have not been f ully con- 



