Recent excavations made at Pompeii and Herculaneum have thrown some further light on various articles of _materia medica_ as it existed in the days just preceding the destruction of those cities. Aloe seems to have been held in high esteem by the practitioners of the time, and was employed, we learn from the historian, in twenty-nine diseases. It was prescribed in doses from 1 to 111 drachmas (about 68 grains), and mixed with wine was employed to stimulate the growth of the hair. Aconite, we find, was used in four diseases; and was supposed to be an antidote to any poison which might exist in the system. Other remedies mentioned include gum acacia, colocynth, elaterium, gold, silver, copper, and elecampane. It is further recorded of the latter drug, that Julia Augusta, daughter of Augustus Cæsar, used to eat the root daily. Of the vegetable remedies about 150 are enumerated, and of these the cabbage seems to have held a prominent place. Other favourite medicines were rye, garlic, anise, mallow, rose, and lily. In the animal kingdom, the remedies contributed were numerous, being mainly the various parts of man and beast. Among some of the least disgusting, hair, blood, and saliva may be mentioned. Scrapings from the bodies of athletes, mixed with the oil with which they anointed themselves, were used as a tonic. The hair of a man torn from the cross was used as a remedy for quartan fever. The hyæna was employed as a medicinal agent in seventy-nine diseases; and the crocodile, chameleon, lion, elephant, camel, and the hippopotamus all contributed certain curative agents. Wool fat was held in great esteem. Of minerals, iron, lead, nitrum, salt, gold, tin, silver, realgar, copper, and misy (a combination of the sulphates of copper and iron) are enumerated. Most of these articles are mentioned by the second Pliny, who was killed during the eruption of Mount Vesuvius which buried Pompeii. CHAPTER VI. ALCHEMY—THE ALCHEMISTS. The word chemistry was used for the first time by Suidas, a lexicographer of the tenth century, and at that time meant an alloy of gold and silver. It is alluded to in connection with the Emperor Diocletian, of whom it is said, that irritated by a revolt of the Egyptians against the laws of the empire, he had all their books of chemistry committed to the flames, so as to punish them for their rebellion by preventing them from carrying on the lucrative business arising out of the melting and working of precious metals. There is little doubt the Egyptians and Greeks were acquainted with certain chemical operations, or what was termed the hermetic science, which was afterwards called alchemy in the first century of the Christian era.