30 white rats were submerged in fresh water until the end of struggle, after which they were removed from the water. Of 15 rats not given artificial respiration, 5 revived. Of 15 other rats given artificial respiration, 4 revived. Of 18 nonrevived rats, in only 2 did the heart stop beating within 6 min. after removal from water, while in the remaining 16, the heart continued to contract for 6-8 min. No ventricular fibrillation was observed. Examination of the lungs showed that the main difference between nonrevived and revived rats was that while the former had tracheae filled with water and foam, in the latter they were free from obstruction. Artificial respiration had no beneficial effect and its was apparently caused by blocking of the airways by water and foam.