( Originally Published Early 1900's )
This term is usually applied to substances used for the purpose of beautifying the skin. They may be divided into two kinds: those which are injurious and even dangerous by reason of some of the ingredients of which they are really composed; and those which, though harmless in themselves, are highly injurious when applied to the skin, because they arrest that insensible perspiration through the pores by which the temperature of the body is preserved and a large part of its refuse matter thrown off. Under the first class fall nearly all those French preparations, so often used in the toilet, such as pearl-white, beruse, rouge, and the like; these are never composed of the harmless materials which are claimed to be employed, and in rouge arsenic has repeatedly been detected. The least objectionable article used as a cosmetic is the mixture of hydrated oxide of bismuth with the subnitrate of the same metal, known as the magister of bismuth. Applied to the skin, its only injurious effects appear to be the interruption of the insensible perspiration referred to above, which after long-continued use produces a tendency to clamminess; a slight nausea, too, is sometimes experienced in consequence of its use, accompanied with spasms and flatulence. It has the disagreeable quality, however, of turning black on the face when exposed to sulphureted hydrogen, a gas frequently met with in badly-ventilated rooms, and, indeed, everywhere that gas or sewers exist. The perfume of onion also has a tendency to turn it black. There is nothing, it must be borne in mind, that can really beautify the skin except bathing, exercise, and a regular compliance with the laws of health.