Certain Chaldean and Persian words were formerly believed to have a particular efficacy against the demons of sickness. The languages of men, it was averred, were not of human origin, but were gifts from the gods; and inasmuch as magic had its source in Chaldea and other Eastern countries, it was reasoned that certain words of the languages spoken in those places were possessed of an inherent magical value.[111:1] Hence these words were used in invocations addressed to spirits. In the popular belief of the ancient Babylonians, illnesses were caused by the entrance into the body of divers aerial spirits, and incantations were the chief means employed for their expulsion. In Accadian medical magic, on the same principle, bedridden patients were treated by fastening about their heads "sentences from a good book."[112:1] Naturally, among nations where such views prevailed, physicians were but little esteemed, and the cure of disease devolved upon exorcists and sorcerers. Medicine was merely a branch of Magic, and not a rational science, as in more enlightened countries. Incantations against the spirits of disease were usually recited by the priests, who were supposed, by reason of their education and training, to be specially expert in the choice of the most efficient formulas. The Chaldean medical amulets were of various kinds. Frequently they consisted of precious stones, engraved with mystic sentences; or strips of cloth, upon which were written talismanic verses, after the manner of Jewish phylacteries. But of whatever form, the chief source of their supposed efficacy appears to have been the words and characters inscribed upon them.[112:2] Gradually, however, a system of therapeutics was evolved, and the use of charms and incantations yielded in a measure to practical methods. The later Assyrian cuneiform inscriptions (about B. C. 1640) contain references to classified diseases;[112:3] and although healing-spells were still largely in vogue, the employment of various herbs and potions became an important feature in Assyrian Medicine.[113:1] The therapeutic methods employed by the priests of Finland in early times were chiefly magical. They exorcised the spirits of disease by means of sacred words and healing-spells, which they believed to be of divine origin.[113:2] Adoration of the hidden forces of nature, and worship of superior beings, gave rise to incantations. It was believed moreover that by the use of appropriate formulas these mysterious powers could be rendered subservient to the will of man. In the popular imagination, even the moon could be made to descend to the earth at the command of an enchantress, by means of an appropriate spell. For, as Virgil sang: _Carmina vel possunt cœlo deducere lunam._