[Verse: "Remove far from me poverty and lies; give me neither poverty nor riches; feed me with food convenient for me."--PROVERBS XXX.]
[Illustration: Fig. 49.--SECTION OF THE STOMACH, &c.]
A. The inner coat of the _stomach_. (The stomach is here represented cut through its length, so that we can see its inside.)
B. The lower extremity of the throat, or _oesophagus_, through which food enters the stomach.
C. The passage out of the stomach, called the _pylorus_, where a muscular contraction prevents the escape of undigested food.
D. The _duodenum_, and the ducts through which the _bile_ and _pancreatic_ juices enter and mingle with our food.
876. _Why do we not feel the food being transmitted through the throat?_
Because the nerves of the body differ in their powers: some are nerves of _feeling_, some of _motion_, and others are nerves of the _senses_. The nerves of feeling are most abundantly distributed to those parts _where feeling is most useful and necessary to us_. But the faculty of feeling our food undergoing digestion would be no service to us whatever; therefore the nerves of _motion_ are plentifully distributed to the throat and stomach, but very few of the nerves of _feeling_--just as many as will tell us when we eat anything _too hot_, or _too cold_, or that the stomach is _out of order_.
877. _Why do we feel uneasy after eating to excess?_
Because the stomach is _distended_, and presses upon the other organs by which it is surrounded.
[Verse: "Who satisfieth thy mouth with good things; so that thy youth is renewed like the eagles."--PSALM CIII.]
878. _Why do we feel drowsy after eating heartily?_
Because, while the stomach is in action, _a great proportion of the blood of the body is drawn towards it_, and as the blood is withdrawn from the other parts of the body, they fall into a state of languor.
879. _Why does blood flow more freely to the stomach during digestion?_
Because the energy of an organ is _increased by the flow of blood_, which supplies the _material_ of which our organs are composed, and in which the _vital essence_, supporting life, resides.
880. _Why does excess in eating bring on indigestion?_
Because the power of the stomach to digest food is _governed by the amount of food required by the system_. It seems to be an instinct of the stomach to hold back food which is in excess, and by indications of pain and disturbance to warn its master that _excess has been committed_.