This suggests that “_short waves_” be employed to supply heat, since it was shown in animal experimentation that by this means it is possible to bring about a thorough warming of the whole animal, which leads to a recovery of the animal with puzzling rapidity. We did not have the proper equipment for a thorough warming of a human being by this means. For this reason the _short wave therapy of the heart_ was tried. This did not have any demonstrable effect. Above all, it is necessary to advise against a practical application of this method, since there exists the danger of prolonged burning even in full consciousness, as the result of cold anaesthesia, even if the treating physician carefully tries to avoid this. The severe difficulty in breathing as well as the formation of foam before the mouth, which reminded one of incipient lung oedema, seemed to indicate oxygen therapy. Therefore this therapy was tried in four experiments. It showed no effect on either the breathing or the heart action. It has been pointed out that the arterial blood appears especially light red. _VI. Death After Cooling in Water_ _Practical and Theoretical Considerations_ Reports to the effect that those who have been rescued at sea are imperilled for a considerable time after rescue has aroused special attention. It has been reported especially that sudden cases of death occurred as much as 20 minutes to 90 minutes after rescue, and that in mass catastrophes these sudden deaths could amount to mass-dying (rescue collapse). These observations have set off far-reaching discussions. Bleeding in the rewarming periphery, break-downs of neural and humoral correlations and similar ideas have been brought up. In contrast to this our experiments give a relatively simple explanation of cold-death under these conditions. With the exception of a single case, a total irregularity of the heart chamber could be definitely demonstrated in all cases of cooling under 30° C. [86° F.], (50 experiments), when the rectal temperature reached 29° C. [84° F.] and usually already at a cooling of 31° C. [88° F.]. The exception was an experiment on an intoxicated subject, which is to be gone into more fully below (_see sec. VII_). _Furthermore heart-death was established clinically in all cases of death observed by us._ In two cases breathing ceased simultaneously with the heart activity. These were cases in which it was specially noted that the neck and the back of the head lay deep in the water. In all remaining cases breathing outlasted the clinical chamber cessation by as much as 20 minutes. In part this was “normal, much decelerated breathing,” in part an angonal form of gasping. As already referred to, an auricular flutter could be demonstrated cardiographically during the irregularity.