The various adjuncts of the sorcerer’s trade are carefully preserved by the Midê or Jessakid in his medicine-bag. A good specimen of this was made out of the skin of a mink, _Putorius vison_, Gapp., and adorned at one end with two fluffy white feathers.[626] Often a flat, black, water-worn pebble will be one of the great treasures in this sack. The virtues of a stone of this type are said to have been put to a curious test on the person of a Jessakid at Leech Lake, Minn., in 1858. The man offered to wager $100 that if he were securely tied up, hand and foot, with stout rope, but having his stone resting on his thigh, he could remove the bonds without assistance. The wager was taken up and the test duly applied; the Jessakid being left alone in his tent tightly and firmly bound. Before long he called out to those on the watch outside the tent that search should be made for the rope at a certain spot nearby. This was done and the rope was found with the knots undisturbed, while the Jessakid was to be seen calmly seated on the ground, smoking a pipe and still bearing his magic black stone on his thigh.[627] French missionaries of the early part of the eighteenth century reported that the Indian wizards of some of the northwestern tribes would take a pebble the size of a pigeon’s egg, and mutter over it certain conjurations. This, they assert, caused the formation of a like stone within the body of the person who was to be bewitched.[628] The medicine-men of certain Canadian tribes of this time were not content with muttered conjurations in treating their patients, but would not infrequently resort to the charm supposed to be exerted by dancing and howling before the sick person. The nervous shock produced by a combination of such grotesque movements and discordant cries might well “rouse” the patient, and perhaps had sometimes good effects in restoring vitality. [Illustration: Canadian Indian Medicine-man. From “Histoire générale des cérémonies, mœurs, et coutumes religieuses de tous les peuples du monde,” by Abbé Banier and Abbé Mascrier. Vol. VII. Paris. 1741. ] An interesting use of the Röntgen rays to detect hidden amulets is noted by Stewart Culin. It was conjectured by Mr. Cushing that some pieces of turquoise, conceived to be the hearts of fetichistic birds, were concealed beneath the heavy wrapping of brown yarn that binds the finger-loops of the prehistoric throwing stick in the Museum of the University of Pennsylvania. This object was too valuable and too fragile to permit of its examination, and therefore the Röntgen rays were used, disclosing the presence of four stone beads, presumably of turquoise, as Mr. Cushing had indicated.[629]