922 THE EXTERNAL SECRETIONS 



out. These procedures have been displaced in more recent years by 

 the method of aspirating or siphoning the gastric juice by means of a 

 long tube of rubber inserted through the esophagus. A number of 

 cases have also been reported in recent years of persons in whom it 

 became necessary to establish a free communication between the 

 gastric cavity and the outside. The first of these has been recorded by 

 the American frontier physician Beaumont/ the subject being the 

 Canadian hunter Alexis St. Martin, whose abdominal and gastric walls 

 had been extensively lacerated by the premature discharge of a gun, 

 so that even the lung protruded from the wound. In healing, a fis- 

 tulous communication was formed between the outside and the cavity 

 of the stomach, but the escape of the gastric contents was prevented by 

 a flap of mucous membrane which acted as a valve and did not allow 

 of an unobstructed view of the interior of this organ. Beaumont 

 determined the time it took to digest meals and found that pork re- 

 quired a longer period for its digestion than beef. He also noted the 

 character of the gastric mucosa in health and disease, and obtained 

 sufficient quantities of pure gastric juice for analysis. The results of 

 these studies are accepted even to-day as wholly accurate. Further- 

 more, he introduced various foods through this fistulous opening and 

 withdrew them again later on to see what changes had taken place in 

 them. 



^ Since the time of Beaumont gastric fistulas have been established 

 in a number of persons suffering from occlusion of the esophagus in 

 consequence of erosion by corrosive alkali. Cases of this kind have 

 been reported by Richet, Sommerfeld and Roder,^ Bickel,^ Umber, ^ 

 Kaznelson,^ and Carlson.^ The subject of the most recent report 

 was operated upon 16 years ago and has since led a normal life, 

 offering himself repeatedly for physiological observation. This same 

 condition may be produced in animals by operative means, the fis- 

 tulous opening in the abdominal wall being permanently closed by a 

 silver cannula. The outside cover of the latter is made so that it 

 can be removed at any time for the purpose of procuring gastric 

 juice. In this catagory also belong the procedures of Heidenhain 

 and Pawlow which permit of the resection and isolation of a particular 

 portion of the stomach and the separate study of its secretion. 



Artificial gastric juice may be prepared by extracting macerated 

 gastric mucosa with dilute hydrochloric acid. This liquid is filtered 

 and warmed to the temperature of the body whenever required for use. 

 For coagulated albumin it should have a strength of 0.16 per cent. 

 Pepsin may be obtained by placing the washed mucosa in alcohol 



1 The Physiology of Digestion, 1833. 



2 Archiv fur Physiol, 1905. 



3 Deutsch. med. Wochenschr., 1906. 

 * Berliner klin Wochenschr., 1905. 



6 Pfliiger's Archiv, xcviii, 1907, 327. 



' Am. Jour, of Physiol., xxxi, 1912, 151. 



