The same Olaus Magnus[280] says that in mines, above all in silver mines, from which great profit may be expected, six sorts of demons may be seen, who under divers forms labor at breaking the rocks, drawing the buckets, and turning the wheels; who sometimes burst into laughter, and play different tricks; all of which are merely to deceive the miners, whom they crush under the rocks, or expose to the most imminent dangers, to make them utter blasphemy, and swear and curse. Several very rich mines have been obliged to be disused through fear of these dangerous spirits. Notwithstanding all that we have just related, I doubt very much if there are any spirits in mountain caves or in mines. I have interrogated on the subject people of the trade and miners by profession, of whom there is a great number in our mountains, the Vosges, who have assured me that all which is related on that point is fabulous; that if sometimes they see these elves or grotesque figures, it must be attributed to a heated and prepossessed imagination; or else that the circumstance is so rare that it ought not to be repeated as something usual or common. A new "Traveler in the Northern Countries," printed at Amsterdam, in 1708, says that the people of Iceland are almost all conjurers or sorcerers; that they have familiar demons, whom they call _troles_, who wait upon them as servants, and warn them of the accidents or illnesses which are to happen to them; they awake them to go a-fishing when the season is favorable, and if they go for that purpose without the advice of these genii, they do not succeed. There are some persons among these people who evoke the dead, and make them appear to those who wish to consult them: they also conjure up the appearance of the absent far from the spot where they dwell. Father Vadingue relates, after an old manuscript legend, that a lady named Lupa had had during thirteen years a familiar demon, who served her as a waiting-woman, and led her into many secret irregularities, and induced her to treat her servants with inhumanity. God gave her grace to see her fault, and to do penance for it, by the intercession of St. Francois d'Assise and St. Anthony of Padua, to whom she had always felt particular devotion. Cardan speaks of a bearded demon of Niphus, who gave him lessons of philosophy. Agrippa had a demon who waited upon him in the shape of a dog. This dog, says Paulus Jovius, seeing his master about to expire, threw himself into the Rhone. Much is said of certain spirits[281] which are kept confined in rings, that are bought, sold, or exchanged. They speak also of a crystal ring, in which the demon represented the objects desired to be seen. Some also speak highly of those enchanted mirrors,[282] in which children see the face of a robber who is sought for; others will see it in their nails; all which can only be diabolical illusions.