Chalcanthum is also prepared in various other ways: the earth which contains it being sometimes excavated into trenches, from the sides of which globules exude, which become concrete when exposed to the action of the winter frosts. This kind is called “stalagmia,”[1641] and there is none more pure. When its colour is nearly white, with a slight tinge of violet, it is called “lonchoton.”[1642] It is also prepared in pans hollowed out in the rocks; the rain water carrying the slime into them, where it settles and becomes hardened. It is also formed in the same way in which we prepare salt;[1643] the intense heat of the sun separating the fresh water from it. Hence it is that some distinguish two kinds of chalcanthum, the fossil and the artificial; the latter being paler than the former, and as much inferior to it in quality as it is in colour. The chalcitis which comes from Cyprus is the most highly esteemed for the purposes of medicine, being taken in doses of one drachma with honey, as an expellent of intestinal worms. Diluted and injected into the nostrils, it acts detergently upon the brain, and, taken with honey or with hydromel, it acts as a purgative upon the stomach. It removes granulations upon the eye-lids, and is good for pains and films upon the eyes; it is curative also of ulcerations of the mouth. It arrests bleeding at the nostrils, and hæmorrhoidal discharges. In combination with seed of hyoscyamus, it brings away splinters of broken bones. Applied to the forehead with a sponge, it acts as a check upon defluxions of the eyes. Made up into plasters, it is very efficacious as a detergent for sores and fleshy excrescences in ulcers. The decoction of it, by the contact solely, is curative of swellings of the uvula. It is laid with linseed upon plasters which are used for relieving pains. The whitish kind is preferred to the violet in one instance only, for the purpose of being blown into the ears, through a tube, to relieve deafness. Applied topically by itself, it heals wounds; but it leaves a discoloration upon the scars. It has been lately discovered, that if it is sprinkled upon the mouths of bears and lions in the arena, its astringent action is so powerful as to deprive the animals of the power of biting. CHAP. 33. (13.)—POMPHOLYX.