230 



DIGESTION. 



and patches of Peyer of the intestines. These are not always present in the adult, but 

 are generally found in children. They are usually most abundant over the greater curva- 

 ture, though they may be found in other situations. In their anatomy they are identical 

 with the closed follicles of the intestines and do not demand special consideration in this 

 connection. 





FIG. 57. Peptic and mucous glands ; magnified 100 diameters. (Sappey.) 



A. Peptic gland from the middle portion of the stomach : 1, excretory canal; 2, 2, 2, the three principal branches of 



the gland ; 3, 8, 3, secondary branches filled with rounded cells. 



B. Peptic gland from the pyloric portion: 1, excretory canal; 2, 2, the two principal branches; 3, 3, terminal culs- 



de-sac. 



C. Mucous gland from the pyloric portion : 1, excretory canal; 2, 2, the two branches; 3, 3, 3, 3, 3, secondary branches ; 



4, 4, 4, small, terminal, racemose glands. 



Gastric Juice. 



At the present day it seems profitless to argue the question of the existence of a 

 digestive fluid in the stomach ; and the discussions of the earlier physiologists as regards 

 the possibility of the existence of a fluid capable of dissolving the articles of food have 

 only an historical interest. Our definite knowledge of the most important physiological 

 properties of this fluid dates from the celebrated observations of Dr. Beaumont on Alexis 

 St. Martin, the Canadian, who had a large fistulous opening into the stomach. These 

 observations were commenced in May, 1825, and were continued for a number of years. 

 The first publication of them was in the Philadelphia Medical Recorder, in 1826. 



Mode of obtaining the Gastric Juice. The ingenious experiments of Dr. Beaumont 

 upon the case of St. Martin gave an impulse to the study of digestion and pointed out 

 the way in which the action of the gastric juice could be investigated. The fact that Dr. 

 Beaumont noted the action of human gastric juice upon all the ordinary articles of food 

 enabled physiologists to compare with it the properties of the secretion obtained from the 



