was the suitable remedy for all diseases affecting the brain, as apoplexy, epilepsy, melancholia, vertigo, and failure of memory. Tachenius relates that a certain silversmith had the gift of being able to repeat word for word anything that he heard, and this power he attributed to his absorption of particles of silver in the course of his work. It does not appear, however, that all silversmiths were similarly endowed.
The Greek and Latin doctors make no allusion to silver as a medicine, and the earliest evidence of its actual employment as a remedy is found in the writings of Avicenna, who gave it in the metallic state "in tremore cordis, in fœtore oris." He is also believed to have introduced the practice of silvering pills with the intention of thereby adding to their efficacy. To John Damascenus, a Christian saint who lived among the Arabs before Avicenna, is attributed the remark concerning silver, "Remedium adhibitum est, et in omnibus itaque capitis morbis, ob Lunæ, Argenti, et Cerebri sympathicam trinitatem." This association of the moon, silver, and the brain was believed in firmly by the chemical doctors of the sixteenth century, and for a long time a tincture of the moon, tinctura Lunæ, was the most famous remedy in epilepsy and melancholia. A great many high authorities, among them Boyle, Boerhaave, and Hoffmann in the eighteenth century, continued to prescribe this tincture or the lunar pills, but silver gradually dropped out of fashion. A great number of medical investigators since have from time to time recommended the nitrate or the chloride of silver in various diseases, but without succeeding in securing for silver a permanent reputation as an internal medicine.
The Pilulæ Lunares were generally composed of
