Simultaneously with the rigor a severe _difficulty in breathing_ set in with or without narcosis. It was reported that, so to speak, an iron ring was placed about the chest. Objectively, already at the beginning of this breathing difficulty, a marked _dilatation of the nostrils_ occurred. The _expiration was prolonged and visibly difficult_. This difficulty passed over into a rattling and snoring breathing. However, the breathing at this point was not especially deep as in Kussmaul’s breathing nor were any Cheyne-Stokes breathing or Biot’s breathing to be observed. Not in all subjects, but in a great number, a simultaneous hindering during this breathing through very profuse _secretion of mucous_ could be established. Under these conditions sometimes a white, _fine-bubbled foam_ appeared at the mouth which reminded one of an incipient _lung oedema_, though it was not possible to determine this symptom with certainty by clinical auscultation; only a sharpened unclean breath sound was audible. This foam might occur early, that is, at rectal temperatures of 32° C. to 35° C.; [90°-95° F.]. No special significance was to be attributed to this regarding the outcome of the experiment which is the opposite of the described relaxation of rigor. The _rate of breathing increased_ at the beginning of the experiment, but after about 20 minutes it decreased to something like 24 per minute with slight variations. In general a definite _dulling of consciousness_ occurred at the dropping of the body temperature of 31° C. [88° F.] rectal temperature. Next, the subjects still responded to speech but finally answered very sleepily. The _pupils_ dilated markedly. The contraction under light became increasingly weaker. The gaze was directed overhead with a compulsive fixation. After withdrawal from the water _an increase in the reflexes_ was evident in spite of the rigor, and regularly a very marked drawing up of the testicles occurred which practically disappeared into the abdomen. Early in the experiment the _face_ was pale. After 40 to 50 minutes _cyanosis_ appeared. With this the face appeared redder, the mucous membrane bluish-red. The skin veins were not maximally collapsed and were virtually always penetrable. The _heart activity_ showed a constant change independent of all other individual variations, which was noticeable in all subjects. Upon introduction into the water with narcotized subjects as well as nonnarcotized subjects, the heart rate went suddenly to about 120 per minute. At a rectal body temperature of about 34° C. [93° F.] it then began to become increasingly slower and to sink continuously to about 50 per minute.