An extremely strange type of amulets found occasionally in Gallic sepulchres are disks made from human skulls. It appears to be a well-ascertained fact that the operation of trephining was performed at this early date, almost if not quite exclusively in the case of infants, and it is believed principally for the cure of epilepsy. If the child survived the operation its skull was thought to have acquired a certain magic power. This idea had its rise in the belief that epilepsy was the result of an indwelling evil spirit, so that if the disease disappeared as a result or sequence of the operation, this evil spirit was believed to have made his way out through the aperture. On the eventual death of one whose skull had been successfully trephined, disks were sometimes cut just on the edge of the opening through which the possessing spirit had slipped out, leaving as a trace of his passage some of his diabolic but still potent virtue.[586] That the superstition regarding these cranial disks lasted well into the sixteenth century, even among some of the educated, is proven by the fact that on a bracelet which belonged to and was worn by Catherine de’ Medici, one of the talismans was a piece of a human skull. Attention was first called to the strange amulets taken from the human skull by the operation of trephining, by M. Prunetière, at a meeting of the French Association for the Advancement of Science, held in Lyons in 1873.[587] The specimen he then exhibited came from a sepulture in the department of Lozère. This particular example showed a break on the edge, and M. Paul Broca has conjectured that a small piece may have been chipped off, so that it might be pulverized and administered as a powder to persons suffering from disease of the brain, a treatment favored by those who doubted the generally-believed supernatural origin of epilepsy, and suspected its source in some lesion of the brain or of the meninges. For this, of course, no more efficient remedy could suggest itself, according to the old sympathetic theory of medicines, than a powder made from the skull of one who had been an epileptic. These skull-amulets have been unearthed in neolithic burials in various parts of France, a considerable number having been found by M. de Baye and others in the department of Marne; a specimen was also found in an Algerian sepulture by General Faidherbe.