1 70 Physiology. 



to sugar, but only a small part, owing to the short time of 

 mastication. The bulk of the starch is unchanged. Some 

 of the proteid is already changed to peptone. Part is still 

 proteid, while part is in an intermediate stage between 

 proteid and peptone. Fat is melted by the heat of the 

 mouth and stomach, and is more or less divided into small 

 drops by mastication and the movements of the stomach. 

 For instance, in eating bread and butter, the m.elting butter 

 will be finely mixed with the bread as it is chewed. The 

 water in the chyme was partly taken as such, and partly 

 derived from the saliva and gastric juice. There are also 

 present ptyalin, pepsin, mucus, salts, and some indigestible 

 substances. At intervals the sphincter muscles of the 

 pylorus relax, and the contractions of the stomach send the 

 liquid mixture into the intestines by spurts. 



Heart-burn. Heart-burn is a burning feeling in the 

 stomach and lower part of the chest caused by indigestion. 

 There is a fermentation in the stomach, usually producing 

 an acid or sour stomach. 



Effects of Alcohol on the Stomach. Since foods go 

 immediately to the stomach, and are detained there some 

 time, they exert their first decided influence there. This 

 is especially true of alcohol. The stomach receives the 

 full force of the blow, so to speak. The first effect of a 

 small amount of alcohol is to produce congestion of the 

 stomach. If alcohol is habitually taken, there is likely 

 to be a permanent congestion, or inflammation, of the 

 stomach. And this, in time, may result in an ulcerated 

 condition from which it is difficult for the stomach to 

 recover. 



Alcohol retards Digestion. For generations it has been 

 generally believed that alcoholic drinks, especially wines, 



