32 



THE GASTRIC JUICE 



out on a plate ; it was at first alkaline, then at the 

 end of some time it became acid. In those days 

 ( 1 8 1 3) this experiment was a real embarrassment 

 to the men who believed in the existence of a 

 special gastric juice : we have now no need to 

 refute it. 



"These few instances suffice to show how the 

 physiologists were unsettled as to the nature and 

 properties of the gastric juice. Then (1823) the 

 Academy had the happy idea of proposing diges- 

 tion as a subject for a prize. Tiedemann and 

 Gmelin in Germany, Leuret and Lassaigne in 

 France, submitted works of equal merit, and the 

 Academy divided the prize between them. The 

 work of Tiedemann and Gmelin is of especial 

 interest to us on account of the great number of 

 their experiments, from which came not only the 

 absolute proof of the existence of the gastric juice, 

 but also the study of the transformation of starch 

 into glucose. Thus the theory of digestion entered 

 a new phase : it was finally recognised, at least 

 for certain substances, that digestion is not simply 

 dissolution, but a true chemical transformation." 

 (CI. Bernard, loc. cit.) 



In 1825 Dr William Beaumont, a surgeon in 

 the United States Army, began his famous experi- 

 ments on Alexis St Martin, a young Canadian 

 travelling for the American Fur Company, who 

 was shot in the abdomen on 6th June 1822, and 

 recovered, but was left with a permanent opening 

 in his stomach. Since the surgery of those days 

 did not favour an operation to close this fistula, 

 Dr Beaumont took St Martin into his service, and 

 between 1825 and 1833 made a vast number of 



