In testing those salts with which it was necessary to use dilutions greater than m/8, the dilution was made with a neutral fluid consisting of sodium chloride and magnesium chloride. It was found that m/6 NaCl solution increased to a very slight extent the peristaltic movements. By adding to 10 c.c. m/6 NaCl, 0.5 c.c. m/6 MgCl_{2}, a fluid was obtained which had apparently neither stimulating nor inhibiting effects. In addition to solutions made up by dilution with this neutral fluid, others were used in which the salt solutions were diluted with distilled water. Practically the same results were obtained in both cases. It was found that 1 c.c. m/320 BaCl_{2} solution applied locally to the intestine is sufficient to cause strong peristaltic movements in a rabbit. This quantity contains about 0.00076 gm. barium chloride. In the case of sodium citrate, the concentration must be considerably greater. No solution of this salt more dilute than m/80 is active in a rabbit. Of all the purgative salts, barium chloride is by far the most powerful. If a drop of m/8 BaCl_{2} be placed on the serous surface of an intestinal loop, or if a small area be moistened with this solution by means of a camel’s hair brush, the muscle beneath the moistened area will almost immediately contract so that a ring-like constriction of the intestine is formed. This often is so sharply marked that it suggests the effect produced by tying a ligature around the intestine. This constriction remains for a few moments, and then gradually moves along the loop in the direction of the normal peristalsis. If the solution be injected into the muscle of the intestine at any point with a hypodermic needle, a similar sharp constriction takes place. If also a few drops be injected directly into a branch of the superior mesenteric artery, all that part of the loop supplied by the arterial branch will contract violently. These statements are true also in the case of sodium citrate, fluoride, sulphate, etc.; the action of these salts, however, is less powerful. It must be added here also that the actual passage of faeces may be produced within an hour by the application of the purgative salts to the serous surfaces of the intestine. This takes place most quickly with barium chloride. It is possible to observe directly through the semi-transparent walls of the intestine the rapid passage of faecal masses from one loop to another.