Abstract
Investigations on the influence of natural Nauheim standing and running effervescent CO2 thermo-saline baths on the subcutaneous CO2 and O2 tension in gas under the skin in rabbits showed a decrease of the CO2 tension in all experiments. The O2 tension increased in 50 per cent. of the experiments, in the others it remained unaffected. The results are interpreted as due to an increase in ventilation and an increase in peripheral blood-flow, the peripheral blood-vessels being dilated. Plain water baths of the same temperature and duration did not show this effect on the peripheral circulation, both CO2 and O2 tension being decreased after the bath. The relations between these researches and other investigations on the effect of natural thermo-saline baths are discussed as well as the difference between the effect of natural and artificial baths. The special curative properties of fresh natural mineral springs are in some way connected with the composition of the salts as complex compounds and their molecular structure. These complex compounds being decomposed by heat, light or access of air, the special activity is lost. The presence of the salts as complex compounds in fresh natural mineral springs is supposed to be due to the special geological conditions under which these compounds are formed.