CERUMEN, (Germ. Okrenschmalz. )—This secretion, formed by the glands of the ex ternal ear, has been examined by Fourcroy and Vauquelin, and more in detail by Ber zelius.* According to Vauquelin it consists of 0.625 of a brown butyraceous oil, soluble in alcohol, and 0.375 of an albuminous sub stance, containing a peculiar bitter extrac tive matter. Berzelius observes, that, when first secreted, cerumen appears as a yellow milky fluid, which gradually acquires a brown ish colour and viscid consistency. Digested in ether it imparts to it fatty matter, which re mains when the ethereal solution is distilled off water ; it has a soft consistence, is nearly co lourless, and contains stearin and elain sepa rable by alcohol ; it is easily saponified, and the soap which it forms has a rank unpleasant smell and taste; and when decomposed by mu riatic acid, the fatty acids separate in the form of a white powder, which rises with difficulty to the surface, and fuses at about 105°. The portion which. remains after the action of ether imparts a yellow colour to alcohol, and on its evaporation there remains a yellow-brown ex tractive matter, soluble in water, and leaving after the evaporation of its aqueous solution a yellow, transparent, and shining varnish, which is viscid and inodorous, but intensely bitter; when burned, it exhales a strong animal odour, and leaves an ash of carbonate of potash and carbonate of lime, without any trace of a chlo ride. It is completely precipitated from its aqueous solution by neutral acetate of lead. That part of cerumen which is not soluble in alcohol yields to water a small proportion of pale yellow matter, which, when obtained by evaporation, has a piquante taste ; it is not precipitable by salts of lead, corrosive subli mate, or infusion of galls, and cOntains no traces of phosphoric or chlorine salts. The
residue of the cerumen, insoluble in water and alcohol, gelatinises in acetic acid, but is only partially dissolved by it ; that which is taken up appears to be albumen; and the undis solved portion is brown, viscid, and transpa rent; digested in dilute caustic alkali it imparts a yellow colour, but a small portion only is dissolved ; and as nothing is thrown down by supersaturation with acetic acid and ferrocy anate of potash, it is not albumen that is taken up : the acid solution, however, is copiously precipitated by infusion of galls, so that it contains some peculiar principle. The residue which resists the action of dilute alcali, when boiled in concentrated solution of caustic pot ash, becomes brown, and smells like horns imi larly treated; a part of it seems to form a compound with the alkali insoluble in the ley, but soluble in water, in which respect it re sembles horn, but it differs from it in not being precipitated from its solution by muriatic acid, nor ferrocyanate of potash, and scarcely by infusion of galls. lt appears, therefore, that cerumen is an emulsive combination of a soft fat and albumen, together with a peculiar substance, a yellow and very bitter matter soluble in alcohol, and an extractive substance soluble in water: its saline contents appear to be lactate of lime and alkali, but it contains no chlorides and no soluble phosphates. When cerumen accumulates and hardens in the ear so as to occasion deafness, it is easily softened by filling .the meatus with a mixture of olive oil and oil of turpentine, by which its fatty matter is dissolved.