Still more recently _Dehio_ and especially _Rosin_ have recommended hot baths for girls suffering from chlorosis. In fifty cases of chlorosis, in which other methods of treatment had given negative results, _Rosin_ gave three times a week baths at a temperature of 40° C. (104° F.), lasting at first a quarter of an hour, but later half an hour. After the bath, in those strong enough to bear it, a very short cold douche or cold sponging followed; then the patient had to lie down for an hour. The treatment was carried out for from four to six weeks. Each bath by itself had a notable refreshing effect in these patients, and at the end of the course most of the cases exhibited an improvement in all their symptoms, such as other methods of treatment had failed to produce. The favorable influence exercised by these hot baths, as by steam bath-cabinets, light baths, sun baths, wet packing, and similar sudorific measures, may in part be explained by the dehydration of the system that is thus effected; whilst those who maintain the auto-intoxication theory of chlorosis may regard the diaphoresis as a means for the elimination of noxious substances from the body. Bathing in water aerated with carbonic acid may be recommended for patients suffering from anæmia and chlorosis at this period of life, for the reason that such baths can be tolerated at a lower temperature than baths of ordinary water. The natural mineral waters containing free carbonic acid, and chalybeate waters rich in carbonic acid, when used as baths, are effective principally in virtue of the carbonic acid they contain, which stimulates the skin; this stimulus being conducted by the nervous system from the periphery to the nerve-centres, is reflected thence, and by irradiation exercises a quickening effect on all the processes of nutrition. These baths are usually taken at a temperature progressively reduced from 32° C. to 25° C. (90° F. to 77° F.), and each bath lasts from ten to twenty minutes; they are in most cases taken every other day only. For young girls in whom the menarche is delayed, also for chlorotic patients with amenorrhœa and neuralgic manifestations, chalybeate peat baths are indicated, which influence the peripheral nerves by the exercise of a gentle yet considerable thermic stimulus. These chalybeate peat baths have further been shown to increase the hæmoglobin-richness, the corpuscular richness, and the specific gravity of the blood, transitorily after each bath, but to some extent permanently also, a certain increase enduring after the course is over.