By this method it was possible to study the influence of the salts on the two great activities of the intestine, namely, the muscular movements and the glandular activity. Their action on the secretion is treated of in a later chapter and can only be mentioned here. The increase of these two activities by means of a salt is the essential action of a purgative, and leads, if sufficiently prolonged, to purgation and to the passage of faeces. This passage of faeces does not take place so readily when the intestines are exposed and the animal is under the influence of morphine as it does in a normal animal. The exposure of the intestine for an hour or more apparently renders this action difficult, although not uncommonly the actual passage of faeces is observed under these circumstances. This is always the case with BaCl_{2}. In a rabbit with its intestines visible it was found that the injection of 1-2 c.c. m/8 or m/6 sodium citrate solution into the jugular vein of a rabbit brings about a very marked increase in the peristaltic movements, which begins from 1 to 2 minutes after the injection. The loops are set in active movements and become firm and rounded so that they seem to occupy a greater volume. The movements consist not only of swinging pendulum movements, but of real peristaltic waves which cause the contents of the intestine to move along the gut so that they may be watched through the thin walls. The morphine narcosis of the animal does not seem to interfere with this action of the salt. When these salt solutions are administered subcutaneously they do not act at once, as in the case of intravenous injections. An interval of 10 to 15 minutes elapses after the subcutaneous injection before any influence on the intestine is noticed. The movements then begin as before, the peristaltic movements and pendulum movements gradually increasing in force. In addition to the greater time required for the action of the salt when administered in this way, it is also necessary to give a larger amount than in intravenous injections; 5-10 c.c. m/8 or m/6 solution of sodium citrate must be introduced subcutaneously in order to produce increased peristalsis. If the solution be introduced into the stomach or intestine a similar increase in peristalsis is brought about, but only after a considerable interval. Usually no effect is obtained until 10 to 15 minutes after the injection of the salt into the lumen of the gut. The injection may be made by piercing the wall of the intestine or stomach with a hypodermic needle, and forcing the fluid into the lumen. The quantity of the solution necessary to produce increased peristalsis is about the same as when introduced subcutaneously. The movements begin not particularly in the part of the intestine containing the solution, but simultaneously in all parts.