Not less important, or indeed very dissimilar, are the uses that are made of alumen;[1] by which name is understood a sort of brine[2] which exudes from the earth. Of this, too, there are several kinds. In Cyprus there is a white alumen, and another kind of a darker colour. The difference, however, in their colour is but trifling in reality, though the uses made of them are very dissimilar; the white liquid alumen being employed for dyeing[3] wool of bright colours, and the black, on the other hand, for giving wool a tawny or a sombre tint. Gold, too, is purified[4] by the agency of black alumen. Every kind of alumen is a compound of slime and water, or in other words, is a liquid product exuding from the earth; the concretion of it commencing in winter, and being completed by the action of the summer sun. That portion of it which is the first matured, is the whitest in appearance.

The countries which produce this substance, are Spain, Ægypt, Armenia, Macedonia, Pontus, Africa,[5] and the islands of Sardinia, Melos, Lipara, and Strongyle:[6] the most esteemed, however, is that of Egypt,[7] the next best being the produce of Melos. Of this last kind there are also two varieties, the liquid alumen, and the solid. Liquid alumen, to be good, should be of a limpid, milky, appearance: when rubbed between the fingers it should be free from grit, and productive of a slight sensation of heat. The name given to it is "phorimon."[8] The mode of detecting whether or not it has been adulterated, is by the application of pomegranate-juice; for if genuine, it will turn black on combining with the juice. The other, or solid alumen, is pale and rough in ap- pearance, and turns black on the application of nut-galls; for which reason it is known by the name of "paraphoron."[9]

Liquid alumen is naturally astringent, indurative, and corrosive: used in combination with honey, it heals ulcerations of the mouth, pimples, and pruriginous eruptions. The remedy, when thus used, is employed in the bath, the proportions being two parts of honey to one of alumen. It has the effect, also, of checking and dispersing perspiration, and of neutralizing offensive odours of the arm-pits. It is taken too, in the form of pills, for affections of the spleen, and for the purpose of carrying off blood by the urine: incorporated with nitre and melanthium,[10] it is curative of itch-scab.

There is one kind of solid alumen, known to the Greeks as "schiston,"[11] which splits into filaments of a whitish colour; for which reason some have preferred giving it the name of "trichitis."[12] It is produced from the mineral ore known to us as "chalcitis,"[13] from which copper is also produced, it being a sort of exudation from that mineral, coagulated into the form of scum. This kind of alumen is less desiccative than the others, and is not so useful as a check upon bad humours of the body. Used, however, either in the form of a liniment or of an injection, it is highly beneficial to the ears; as also for ulcerations of the mouth, and for tooth-ache, if retained with the saliva in the mouth. It is employed also as a serviceable ingredient in compositions for the eyes, and for the generative organs in either sex. The mode of preparing it is to roast it in crucibles, until it has quite lost its liquid form.

There is another variety of alumen also, of a less active nature, and known as "strongyle;"[14] which is again subdivided into two kinds; the fungous, which easily dissolves in any liquid, and is looked upon as altogether worthless; and the porous, which is full of small holes like a sponge, and in pieces of a globular form, more nearly approaching white alumen in appearance. It has a certain degree, too, of unctuousness, is free from grit, friable, and not apt to blacken the fingers. This last kind is calcined by itself upon hot coals, unmixed with any other substance, until it is entirely reduced to ashes.

The best kind of all, however, is that called "melinum,"[15] as coming from the Isle of Melos, as already mentioned; none being more effectual for acting as an astringent, staining black, and indurating, and none assuming a closer consistency. It removes granulations of the eye-lids, and, in a calcined state, is still more efficacious for checking defluxions of the eyes: in this last form, too, it is employed for the cure of pruriginous eruptions on the body. Whether taken internally, or employed externally, it arrests discharges of blood; and if it is applied with vinegar to a part from which the hair has been first removed, it will change into a soft down the hair which replaces it. The leading property of every kind of alumen is its remarkable astringency, to which, in fact, it is indebted for its name[16] with the Greeks. It is for this property that the various kinds are, all of them, so remarkably good for the eyes. In combination with grease, they arrest discharges of blood; and they are employed in a similar manner for checking the spread of putrid ulcers, and for removing sores upon the bodies of infants.

Alumen has a desiccative effect upon dropsical eruptions; and, in combination with pomegranate juice, it removes diseases of the ears, malformed nails, indurations resulting from cicatrization, hangnails, and chilblains. Calcined, with vinegar or nut-galls, in equal proportions, it is curative of phagedænic ulcers; and, in combination with extracted juice of cabbage, of leprosy. Used in the proportion of one part of alumen to two of salt, it arrests the progress of serpiginous eruptions; and an infusion of it in water destroys lice and other parasitical insects that infest the hair. Employed in a similar manner, it is good for burns; and, in combination with the serous[17] part of pitch, for furfuraceous eruptions on the body. It is used also as an injection for dysentery, and, employed in the form of a gargle, it braces the uvula and tonsillary glands. For all those maladies which we have men- tioned as being treated with the other kinds of alumen, that imported from Melos, be it understood, is still more efficacious. As to the other uses that are made of it for industrial purposes, such as preparing hides and wool, for example, they have been mentioned already.[18]