The crapaudine, or toad-stone, is of a dull brown colour. It was believed to possess sovereign virtue against poison from its changing colour when in the presence of any noxious thing: hence it was often worn as a protection in finger rings. Figs. 20 and 21 are good examples of this use. They are both from rings in the Londesborough collection. The belief in the virtues of the toad-stone was not only popular in England, but was one of the fallacies accepted throughout Europe. Though the stone is well-known to geologists as a variety of trap-rock, the accepted belief was that it was found only in the head of the toad. Fenton, writing in 1569, affirms that “there is found in the heads of old and great toads a stone which they call borax or stelon,” and Lupton, some fifty years afterwards, writes: “the crepaudia or toad-stone is very valuable, touching any part envenomed by the bite of a rat, wasp, spider, or other poisonous beast it ceases the pain and swelling thereof.” Ben Jonson also refers to it in his play of “The Fox.” Albertus Magnus, writing about 1275, adds the great wonder that this stone when taken out of the creature’s head has the figure of a toad upon it, while others declare that the stone itself is of the form of a toad. It is a treasure not easily to be procured, for the toad “envieth much that man should haue that stone,” declares Lupton, the author of “A Thousand Notable Things,” hence it was very necessary to beware of useless counterfeits, and this old writer gives us a ready means of detecting them. “To know,” says he, “whether the toad-stone called crepaudia be the righte and perfect stone or not, holde the stone before a toad so that he may see it, and if it be a right and true stone the toad will leap towards it, and make as though he would snatch it from you,” a proceeding that must have required a considerable amount of nerve on the part of anyone duly impressed with the fear of the deadly venom of the creature. [Illustration: FIG. 20.] [Illustration: FIG. 21.]