We are therefore justified in saying that the appetite is the first and mightiest exciter of the secretory nerves of the stomach, a factor which embodies in itself a something capable of impelling the empty stomach of the dog in the sham feeding experiment to secrete large quantities of the strongest juice. A good appetite in eating is equivalent from the outset to a vigorous secretion of the strongest juice; where there is no appetite this juice is also absent. To restore appetite to a man means to secure him a large stock of gastric juice wherewith to begin the digestion of the meal. LECTURE V PERIOD OF OCCURRENCE AND IMPORTANCE OF THE PSYCHIC OR APPETITE JUICE IN THE SECRETORY WORK OF THE STOMACH--THE INEFFICIENCY OF MECHANICAL STIMULATION OF THE NERVOUS APPARATUS OF THE GASTRIC GLANDS The psychic secretion is the normal commencement, in the majority of cases, of secretory activity on the part of the gastric glands. If the meal be subdivided and administered at intervals, the psychic juice appears each time--Demonstration of “appetite juice” in a dog with an isolated gastric _cul-de-sac_. The work of the gastric glands if appetite juice be avoided by introducing food through a gastric fistula unperceived by the animal--Digestion of flesh by the stomach with and without sham feeding--Duration of the secretory influence of sham feeding--After the cessation of the psychic effect, how is the secretory work of the stomach maintained?--Experiments to prove the ineffectiveness of mechanical stimulation: excitation of the mucous membrane by means of a glass rod, a feather, a puff of sand, and by rhythmic dilatation of an india-rubber ball--Contact between the food and the stomach-wall may indirectly call the activity of the glands into play by awakening or increasing the desire for food.