364 COLLOIDS IN BIOLOGY AND MEDICINE 



can, indeed, look back upon an honorable and ancient past. Dios- 

 CORIDES recommended kaolin (bolus alba) as a dressing for erysipelas, 

 poisonings and many other conditions. Throughout antiquity and 

 the middle ages adsorption therapy retained its reputation until 

 modern chemistry, which could not explain its action, delivered its 

 quietus and looked derisively on some nature-therapeutists who em- 

 ployed it (Claypastor, Father Kneipp). STUMPF deserves credit for 

 having retested the clinical advantages from the use of kaolin, which 

 as a therapeutic measure had been forgotten. 



The scientific clinical application of adsorption is the product of 

 the past year. During the war with its severe enteric infections 

 (cholera, dysentery, typhoid) it has triumphed unexpectedly. 



In addition to kaolin and silicic acid (prepared by the Gesell- 

 schaft fur Electroosmose) charcoal has been employed most. Char- 

 coal has yielded good results in stomach conditions (hyperchorhydria 

 and fermentation) , and also in obesity cures it has been employed by 

 LICHTWITZ who removes by it the important ingredients of the 

 chyme (acids and enzymes, see p. 329), and fills the stomach so as to 

 satisfy the distressing pangs of hunger. Gastric hypersecretion is 

 also treated by gum arabic, starches, bismuth subnitrate and talcum. 



In the serious infectious intestinal diseases, cholera, dysentery and 

 typhoid, as well as in the gastrointestinal diseases of infants, kaolin 

 and charcoal act not only by adsorption of toxins produced by the in- 

 fectious agents but also by the adsorption of the bacteria themselves. 



Finally we must mention the original use of kaolin and charcoal, 

 in purulent and dissection wounds as well as in catarrhs (vagina and 

 nose) and in exuberant carcinomata. The action is the same here as 

 in the intestinal infections. Naturally, only sterile preparations are 

 employed in modern surgery. 



A further advance has been to impregnate charcoal with drugs which 

 are then gradually yielded. A good effect was obtained in typhoid with 

 iodine and thymol. A preparation of charcoal impregnated with sul- 

 phur (eucarbon) is used as a mild laxative which at the same time re- 

 lieves flatulence by adsorption of bacteria and putrefactive material. 



Dermatologists employ powders extensively for a cooling effect. 

 Obviously the powders absorb the water which emerges from the 

 skin and as a result of their surface development accelerate evap- 

 oration; to a certain extent they amplify the skin surface. Good 

 results may be obtained on burns and inflammatory edemas with 

 thick layers of kaolin. A cooling (febrifuge) effect may be obtained 

 according to P, G. UNNA * l by painting the entire body with a thin 

 layer of gelatin or collodion; this effect is explained by the mag- 

 nification of the body surface (see p. 355). 



