As stated above in a previous section, I have made a large number of experiments to determine whether or not an increased secretion is actually caused by the saline purgatives, and have found by measurements that with some of the salts this increase is very marked. These results have been already published,[47] and the tables and a part of the description given below are taken from this paper. Rabbits and dogs were used in these experiments. In the case of the rabbits anaesthesia was produced by the subcutaneous injection of 4-5 c.c. 1% morphine hydrochlorate. The rabbits were not full grown, their average weight being not more than 1,200 g. The same amount of morphine was given also to the dogs, and was supplemented by ether. The abdominal cavity was opened and a loop of considerable length tied off with ligatures. In the rabbit the upper part of the small intestine was selected and the upper ligature placed just below the entrance of the common bile duct. The second ligature was tied 25 to 30 cm. lower down. At the lower end of the loop a large mouthed cannula was inserted from which the fluid could be drained by gently lifting the successive parts of the loop, a process made more easy by placing the animal board at a considerable angle with the table. All of this was done as rapidly as possible, so that the loops would be exposed as little as possible to the air. After the loop had been emptied of what it contained in this way, the intestines were covered over with filter paper soaked in warm m/6 NaCl solution, and this again covered with a towel wet with warm water, and over it all a woolen cloth. In this way the loops were protected fairly well from drying and loss of heat. The contact with the wet filter paper did not seem in any way to affect the intestine. Other experiments were made with the filter paper raised from the intestine by a wire tent. I found that if these precautions against loss of heat and drying were neglected the secretion did not take place. The greatest care must be exercised in this respect since the slightest cooling seems to inhibit the secretory activity of the intestine.