Page:Hatha yoga - or the yogi philosophy of physical well-being, with numberous excercises.djvu/33

Rh of "swallowing." The process of converting the starchy portion of the food into sugar, or glucose, which is begun by the saliva in the mouth, is continued as the food passes into and down the gullet, but nearly, or entirely ceases, when the food once reaches the stomach, which fact must be considered when one studies the subject of the advantage of a deliberate habit of eating, as, if the food is hastily chewed and swallowed, it reaches the stomach only partially affected by the saliva and in an imperfect condition for Nature's subsequent work.

The stomach itself is a pear-shaped bag with a capacity of about one quart or more in some cases. The food enters the stomach from the gullet on the upper left-hand side, just below the heart. The food afterwards leaves the stomach on the lower right-hand and enters the small intestine by means of a peculiar sort of valve, which is so wonderfully constructed that it allows the matter from the stomach to pass easily through it, but refuses to allow anything to work back from the intestine into the stomach. This valve is known as the "Pyloric Valve" or the "Pyloric Orifice," the word "Pyloric" being derived from the Greek word which means "gatekeeper"—and indeed this little valve acts as a most intelligent gatekeeper, always on the watch, never asleep.

The stomach is a great chemical laboratory in which the food undergoes chemical changes which allow it to he taken up by the system and changed into a nourishing material which is converted into rich, red blood which courses all over the body,