Page:Hatha yoga - or the yogi philosophy of physical well-being, with numberous excercises.djvu/38

38 and then into glucose, thus rendering it soluable. This chemical change is rendered possible by the action of the pytaline in the saliva acting as a ferment and changing the chemical constitution of those substances for which it has an affinity.

Digestion is performed in the stomach and small intestines and consists in the conversion of the food-mass into products capable of being absorbed and assimilated. Digestion begins when the food reaches the stomach. The gastric juice then pours out copiously, and, becoming mixed up with and churned into the food mass, it dissolves the connective tissue of meat, releases fat from its envelopes by breaking them up and transforms some of the albuminous material, such as lean meat, the gluten of wheat and white of eggs, into albuminose, in which form they are capable of being absorbed and assimilated. The transformation occasioned by stomach digestion is accomplished by the chemical action of an organic ingredient of the gastric juice, called pepsin, in connection with the acid ingredients of the gastric juice.

While the process of digestion is being performed by the stomach the fluid portion of the food-mass, both that which has entered the stomach as fluids which have been drunken, as well as the fluids liberated from the solid food in the process of digestion, is rapidly taken up by the absorbents of the stomach and is carried to the blood, while the more solid portions of the food-mass are churned up by he muscular action of the stomach, as we have stated. In about a half-hour the solid portions of the food-mass begin slowly to leave the stomach in