DISEASES OF DIGESTIVE 

 SYSTEM. 



The digestive tract, which starts at the mouth and ends at the 

 •anus, may fairly be described as one long continuous tube which 

 varies in size in different parts; commencing at the mouth it passes 

 to the pharynx, which is also shared with the respiratory tract, 

 as the back of the nose also empties itself into that organ; from 

 the pharynx the tube is continued as the oesophagus, which passes 

 •down the neck side by side with the trachsea (or windpipe); the 

 oesophagus is commonly known as the gullet; this joins the stom- 

 ach, which is nothing more than a large dilatation of the digestive 

 tube; passing out of the stomach the tube becomes very small, and 

 there commence the smallest intestines; the intestines vary in size 

 until some short distance before arriving at the anus (or external 

 opening behind); a short distance from the commencement of the 

 small intestines, not far from the stomach, there is a tube con- 

 nected with and coming from the liver, which empties the con- 

 tents of that organ (the bile) into the intestines; the bile assists 

 in the digestion of the food; this small tube (or duct ) which comes 

 from the liver has also another tube which conveys the secretion 

 of a gland called the pancreas and joins the duct of the liver before 

 it enters the intestine; this gland secretes a fluid called the pacre- 

 atic juice, which also assists in the process of digestion. The 

 process o^ digestion commences in the mouth, where by means of 

 mastication the food is rendered fit to be acted upon by the saliva, 

 the gastric juice which is formed in the stomach, the pancreatic 

 juice and the bile, and finally the various secretions from the 

 glands situate in the walls of the intestines; in plain lan- 

 guage, the process of digestion is one of dissolving all the way 

 along the tube, or of rendering solid food soluble, so that it may 

 be taken up and transferred to its destination by means of .the 

 blood and other channels through which it passes while being dis- 

 tributed over the body for assimilation. 



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