FOOD. 103 



cation. This is contrary to an express law of nature, as may be easily 

 shown. 



Food, on being received into the mouth, has two processes to undergo, 

 both very necessary to digestion. It has to be masticated, or chewed down, 

 and also to receive an admixture of saliva. The saliva is a fluid arising 

 from certain glands in and near the mouth, and approaching in character 

 to the gastric juice afterward to be described. Unless food be well broken 

 down or masticated, and also well mixed up with the salivary fluid, it will 

 be difficult of digestion. The stomach is then called upon to do, beside 

 own proper duty, that which properly belongs to the teeth and saliva, and 

 it is thus overburdened and embarrassed, often in a very serious manner. 

 The pains of indigestion are the immediate consequence, and more remote 

 injuries follow. 



It is therefore to be concluded that a deliberate mastication of our fv 

 is conducive to health, and that fast eating is injurious, and sometimes 

 even dangerous. 



The food, having been properly masticated, is, by the action of the 

 tongue, thrown into the gullet. It then descends into the stomach, not so 

 much by its own gravity, as by its being urged along by the contractions 

 and motions of the gullet itself. The stomach may be considered as an 

 expansion of the gullet, and the chief part of the alimentary canal. It is, 

 in fact, a membranous pouch or bag, very similar in shape to a bagpipe, 

 having two openings, the one by which the food enters, the other that by 

 which it passes out. It is into the greater curvature of the bag that the 

 gullet enters ; it is at its lesser that it opens into that adjoining portion of 

 the canal into which the half-digested mass is next propelled. 



When food has been introduced, the two orifices close, and that which 



iav t -mi the second stage in the process of digestion commences. The 



mass, already saturated with saliva, and so broken down as to expose all 



IK particles to the action of the gastric juice, is now submitted to the action 



of that lluiil, which, daring digestion, is freely secreted by the vessels of the 



iach. The most remarkable quality of this juice is its solvent pov> 

 which is prodigious. 



The food exposed to this dissolving agency is converted into a soft, <; 



pulpy mass, called chyme, which, by the muM-nlar contraction of the 



i on into the adjoining part of the alimentary canal, called 



duodenum. This i> "vnenilly completed in the space of from half an 



hour to two Or three hoiin J the period \arying according to flic nature 



volinin M. and the mastication and in^alivat i-.n it has 



iergone, 



