There is also a “sweet” bran drench used on the continent, in which fermentation is not allowed to take place, the skins being paddled in an infusion of bran in water for a short time only, two to three hours at the most. In addition to the mechanical cleaning action, which the fresh bran has upon the skins, there is also a softening effect due to some constituent of the bran, which is at present not understood. One reason for this, is that the usual drench employed being an acid one, research has practically been confined to the latter. Another method of preparing the bran drench, consists in allowing the required quantity of bran to soak in cold water for several hours; a sufficient quantity of hot water is then added to bring the temperature up to 50° C.; at this temperature the diastatic enzymes in the bran act rapidly on the starch and transform it into easily fermentable sugars. The temperature is allowed to fall to 34° to 35° C., and then a quantity of an old drench is added to start the fermentation. The liquor becomes acid, and in two days usually reaches its maximum acidity, when it is ready for use. The bran is strained off and only the milky liquor used. Such a drench is largely employed in the manufacture of chamois leather, the goods (sheep fleshes) being paddled in it for some hours previous to pressing. The French also use a similar process in the preparation of suede leather. The bran is strained off and only the sour partly fermented and fermenting liquor used. The straining off of the bran also saves working over the beam which would otherwise be required to get rid of the bran adhering to the skins. It has recently been proposed to employ the bacillus bulgaricus, the organism which causes the fermentation of milk in the preparation of Bulgarian and Turkish “Yoghurt” (Bibliography 124) for drenching. Bacillus bulgaricus is capable of producing up to 2·5 per cent. of lactic acid, or about three times the quantity of that produced by ordinary lactic bacteria. Dr. Hugo Kühl (loc. cit.) proposes to cultivate the bacillus in the mother liquors, which are a by-product in the manufacture of milk sugar, and to use such liquor as a drench. Where skim milk or butter milk is to be had, this may also be used. A similar process is already in use in America, where the evaporated product is put upon the market under the name of Dermiforma (see pp. 189 and 194). As a substitute for the drench, and in order to further remove lime after erodin, the late Franz Kathreiner employed a solution of anticalcium, 1 in 500 water, in which the skins remained overnight. Anticalcium is a mixture of sulphonic acids derived from cresols, and has antiseptic properties, so that its action is quite distinct from that of the bran drench. It is put on the market by J. Hauff, Feuerbach, near Stuttgart.