IRISH MOSS, or Carrageen (Irish carraigeen, “moss of the rock”), is a sea-weed (Chondrus crispus) which grows abundantly along the rocky parts of the Atlantic coast of Europe and North America. It is collected for commercial purposes on the west and north-west of Ireland, and in very large quantities on the coast of Plymouth county, Massachusetts, United States. In its fresh condition the plant is soft and cartilaginous, varying in colour from a greenish-yellow to a dark purple or purplish-brown; but when washed and sun-dried for preservation it has a yellowish translucent horn-like aspect and consistency. The principal constituent of Irish moss is a mucilaginous body, of which it contains about 55 per cent.; and with that it has nearly 10 per cent of albuminoids and about 15 per cent, of mineral matter rich in iodine and sulphur. When softened in water it has a sea-like odour, and from the abundance of its mucilage it will form a jelly on boiling with from 20 to 30 times its weight of water. The jelly of Irish moss is used as an occasional article of food, and is a popular remedy in cases of chest disease. It may also be used as a thickener in calico-printing, and in America it is used for fining beer. In the neighbourhood where it is obtained it is utilized for feeding cattle. As found in commerce, Irish moss is frequently mixed with Gigartiηa mammillosa, G. acicularis, and other sea-weeds with which it is associated in growth.