COMPOSITION OF HUMAN GASTRIC JUICE. 197 



down thereby, choleraic symptoms result. Koch produced genuine 

 cholera in animals by opening the abdomen, tying the bile-duct, 

 and then injecting cholera cultures directly into the intestines. 

 It would appear from the evidence taken as a whole that, if 

 the stomach is in a normal condition, cholera germs will be 

 destroyed by the gastric juice. It is not improbable that if the 

 stomach is the seat of catarrhal inflammation, as might be caused 

 by alcohol taken for a long time in excess, the conditions in the 

 stomach-cavity would be favorable to the reception and growth 

 of the cholera spirilla, and the disease be produced. Falk claims 

 that the bacillus of anthrax is destroyed by gastric juice, except 

 when in the sporulating stage, but that this fluid has no effect on 

 the tubercle bacillus. 



Writing on this general subject, Sternberg, in his Manual of 

 Bacteriology, says : " The experiments of Straus and Wiirtz and 

 of others show that normal gastric juice possesses decided germi- 

 cidal power, which is due to the hydrochloric acid contained in it. 

 Hamburger (1890) found that gastric juice containing free acid is 

 almost always free from living micro-organisms, and that it 

 quickly kills the cholera spirillum and the typhoid bacillus, but 

 has no effect upon anthrax spores. Straus and Wurtz found that 

 the cholera spirillum is killed by two hours 7 exposure in gastric 

 juice obtained from dogs, the typhoid bacillus in two or three 

 hours, the anthrax bacillus in fifteen to twenty minutes, and the 

 tubercle bacillus in from eighteen to thirty-six hours. The ex- 

 periments of Kurlow and Wagner, made with gastric juice ob- 

 tained from healthy men by means of a stomach-sound, gave the 

 following results : Anthrax bacilli without spores failed to grow 

 after exposure to the action of human gastric juice for half an 

 hour, but spores were not destroyed in twenty-four hours; the 

 typhoid bacillus was killed in one hour ; the cholera spirillum, the 

 bacillus of glanders, and Bacillus pyocyaneus were all destroyed 

 at the end of half an hour ; the pus cocci showed great resisting- 

 power. Certain bacteria have a greater resisting-power for acids 

 than any of those above mentioned, and some of them may con- 

 sequently pass through the healthy stomach to the intestine in a 

 living condition, but there is good reason to believe that the 

 spirillum of cholera or the bacillus of anthrax would not. On the 

 other hand, the tubercle bacillus and the spores of other bacilli 

 can, no doubt, pass through the stomach to the intestine without 

 losing their vitality." 



The hydrochloric acid of the gastric juice when free certainly 

 destroys many non-pathogenic bacteria introduced with the food, 

 which otherwise might cause it to decompose ; thus both lactic and 

 acetic fermentations are prevented ; it is said, however, that hydro- 

 chloric acid when combined with proteids does not have this 

 power. Cohn explains the action of the free acid by supposing 



