280 DIGESTION. 



irritant, such as tlie bulb of a thermometer, into the 

 stomach, excited at once the secretion of gastric fluid. 

 This could be drawn off with a caoutchouc tube, and could 

 often be obtained to the extent of nearly an ounce. The 

 introduction of alimentary substances caused a much more 

 rapid and abundant secretion of pure gastric fluid than 

 the presence of other mechanieal irritants did. No in- 

 crease of temperature could be detected during the most 

 active secretion ; the thermometer introduced into the 

 stomach always stood at 100 Fahr., except during mus- 

 cular exertion, when the temperature of the stomach, like 

 that of other parts of the body, rose one or two degrees 

 higher. 



M. Blondlot and subsquently M. Bernard, and since 

 then, several others, by maintaining fistulous openings into 

 the stomachs of dogs, have confirmed most of the facts 

 discovered by Dr. Beaumont. And the man St. Martin, 

 has frequently submitted to 'renewed experiments on his 

 stomach, by various physiologists. From all these obser- 

 vations it appears, that pepper, salt, and other soluble 

 stimulants, excite a more rapid discharge of gastric fluid 

 than mechanical irritation does ; so do alkalies generally, 

 but acids have a contrary effect. When mechanical irri- 

 tation is carried beyond certain limits so as to produce 

 pain, the secretion, instead of being more abundant, 

 diminishes or ceases entirely, and a ropy mucus is poured 

 out instead. Very cold water, or small pieces of ice, at 

 first render the mucous membrane pallid, but soon a kind 

 of reaction ensues, the membrane becomes turgid with 

 blood, and a larger quantity of gastric juice is poured out. 

 The application of too much ice is attended by diminution 

 in the quantity of fluid secreted, and by consequent re- 

 tardation of the process of digestion. The quantity of the 

 secretion seems to be influenced also by impressions made 

 on the mouth ; for Blondlot found that when sugar was 

 introduced into the dog's stomach, either alone, or mixed 



