62 DEMULCENTS AND EMOLLIENTS 



Some, like matico, tow, lint, or pressure, mechanically check 

 blood-flow from superficial vessels ; others, like most astrin- 

 gents and caustics, coagulate albumin, and thus plug the 

 leaking vessels. When thus used, the blood is removed by 

 a piece of lint or a sponge, and the part lightly pressed, so 

 that the blood-vessels may be more readily seen, and the 

 caustic applied to them with precision, and with as little 

 destruction as possible of surrounding textures. The effect 

 of the styptic may be seconded by equable pressure and 

 application of cold. Others again, like adrenalin, ergot, 

 digitalis, ether-spray, and antipyrine in tannic acid solution, 

 contract capillary vessels, while lead acetate and calcium 

 chloride act by increasing the coagulability of the blood, the 

 former also contracting arterioles. Astringent and caustic 

 agents are also used as coagulants to prevent the flow of 

 synovia from open joint capsules and bursse. 



DEMULCENTS soothe and protect parts with which they 

 come into contact, act chiefly mechanically, and closely 

 resemble emollients. They include gums, mucilage, linseed, 

 cotton-wool and collodion, fuller's earth, starch, treacle, 

 gelatin, albumin, fats, oils, glycerin, and milk. They take 

 the place of mucus and other natural demulcents, where 

 these are deficient or wanting. They lubricate or defend 

 abraded or irritable parts from external injury, acrid dis- 

 charges, and poisonous matters. They are employed in 

 solution, spray, draught, or enema, to relieve dry, irritable 

 conditions of the skin, respiratory, digestive, and urino- 

 genital membranes by local application. 



EMOLLIENTS soften, soothe, and relax the parts to which 

 they are applied. They resemble demulcents, and include 

 many of the articles specified in that class, as well as those 

 substances which absorb and retain heat and moisture. 

 They are represented by fomentations, poultices, and 

 spongio-piline, and by folds of lint, flannel, or woollen 

 cloth, wrung out of hot water, and covered with water- 

 proofing. (See Poultices and Fomentations.) Pats, oils, 

 lanoline, vaseline, paraffin, with soap and other liniments, 

 are also emollients. Fatty emollients rubbed into the 

 skin soften and supple it ; and when applied with smart 

 and continued friction, they also increase tissue changes, 



