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Knight's Mechanical Encyclopedia (ed. Knight), M. (search)
n amber and the magnet, and supposed them to be living because they had a moving force. From Eastern Asia has been handed down the knowledge of the directive force and declination of a freely suspended magnetic bar; from Phoenicia and Egypt the knowledge of chemical preparations (as glass, animal and vegetable coloring substances, and metallic oxides); and from India the general use of position in determining the greater or less value of a few numerical signs. — Humboldt. Aetius, A. D. 500, refers to the use of the magnet for the cure of disease. He says: We are assured that those who are troubled with gout in their hands or their feet, or with convulsions, find a relief when they hold a magnet in their hand. Several eminent physicians of the fifteenth century affirmed its virtues as a cure for toothache, and a little later we read of magnetic toothpicks for the same purpose. The deviation of the compass was known before Columbus, but it was assumed to be uniform. The