Origin and Properties

This is the Chondrus crispus (Fucus crispus, Linn.), which grows on rocks and stones on the sea coasts of Europe, and in peculiar abundance on the Atlantic shore of Ireland, where it is chiefly gathered. it consists of a slender frond, sometimes a foot in length, gradually expanding as it ascends to a width of two or three lines, then dividing and subdividing into linear lobes, and often much curled in the direction of its length. it is translucent, of a cartilaginous consistence, a yellowish or yellowish-white colour, a slight odour, and a peculiar but feeble taste, recalling that of sea plants in general. it swells and softens with cold water, but does not dissolve. Boiling water extracts nearly 80 per cent. of a principle analogous to pectin, but somewhat peculiar, for which the name of carrageenin has been proposed. Minute quantities of iodine and bromine have been detected in it; but their presence is doubted by some, and they can scarcely add appreciably to the virtues of the moss.

Medical Effects and Uses

Irish moss is simply demulcent and nutritive, and may be used for the same purposes as the amylaceous substances already described, over which it has little if any advantage. it has been recommended in pectoral diseases, scrofulous complaints, and chronic diseases of the bowels and urinary organs, under the impression that it possessed special virtues; but time has fixed its value as above stated. it is prepared in decoction by boiling an ounce in a pint and a half of water to a pint, and flavoring to suit the taste. it is often also boiled with milk, when the latter is thought to be indicated. No doubt, an exclusive diet of Irish moss with milk would prove extremely useful in many cases of disorder of the bowels. in order to remove adhering substances which may injure its flavour, it should be steeped, for a few minutes, in cold water before the decoction is prepared.