It has recently been shown by experiments conducted by Strasser and Blumenkranz[237] that baths taken for a long time and at a temperature of 34-35°C., are able to create an increased elimination, not only of a considerable quantity of water, but of common salt also, and of the products of decomposition of nitrogenous matter. Footnote 237: Strasser und Blumenkranz: “Die Wirkung indifferenter und schweisstresbender Bader bei Nephritis,” Med. klin., Beichfte Hefte 6, 1907. These authorities come to the conclusion that through bathing there can be brought about a true increase not only of the water-secreting activity of the kidneys, but also of their ability to eliminate nitrogenous end-products and salt. They found an increase of diuresis to double the usual amount and an increased elimination of from 50 to 100 per cent. of nitrogen, and from 100 to 200 per cent. of salt. According to Liebermeister, Loewy, Rubner, and others, the processes of oxidation can be increased by cold baths from 50 or 100 to 200 per cent., and by hot baths, according to Winternitz and Rubner, 50 to 100 per cent. Rubner also asserts that the processes of oxidation can be wonderfully increased by cold douches. There can thus be no doubt that baths are able to influence the conditions of the kidneys in a very favorable way, and that their vitality may be augmented by the daily use of the bath. The drawback to the bath is that so many people easily catch cold afterward; to prevent which, such persons should not wet the head, and especially the back part of it, as otherwise catching cold is easily effected; and it is also of importance that the bath-room should not be left while the skin is hot. The best way is to allow cold water gradually to enter the bath, getting out directly there is the least sensation of cold. The rule should be not to leave the bath when the skin is hot and red and the pores wide open, without letting cold water contract them by taking a short douche, and on getting out of the bath the skin should be quickly dried by energetic friction with a rough towel until the skin becomes quite scarlet. Not sufficiently drying the skin will cool it rapidly, and even intensely, owing to the evaporation of the water from the periphery, and surely cause a severe cold. To prevent the habit of catching cold the best way is to accustom the skin to the action of cold water. Rubbing the skin with a cold wet towel until the skin glows, especially the chest and extremities, is a good way to effect this, beginning in warm summer weather and continuing through the winter, but not _vice versa_. Decidedly the best preventative to catching cold is to get the skin accustomed to fresh air and cold water.