hand, telling him to show it to the authorities and say that it was St. Mark’s ring, in proof of which they would find that its carefully locked receptacle in the cathedral was empty.[516] This proved to be true, and the gondolier received a liberal pension as a reward for having aided, however humbly, in the preservation of Venice by St. Mark.[517] The marvellous ring of Gyges may have suggested to Abbot Tritheim, or Trithemius, of Spandau (1462–1516) the idea of fabricating a ring which would give the wearer the power of becoming invisible at will. The Abbot asserts that he had made such a ring out of the material called electrum, a natural alloy of gold and silver, having the color of amber. To possess the requisite power, the ring must be cast at the hour at which the person designing to use it was born, and it should be inscribed with the word “Tetragrammaton” signifying the four letters composing the Ineffable Name. When this ring was placed upon the thumb of the left hand, the wearer immediately became invisible. Besides this virtue, when worn on any finger, the ring preserved the wearer from poison and betrayed the presence of enemies by changing color.[518] Rings bearing the Latin inscription “Jesus autem transiens per medium illorum” (Jesus, however, passing through their midst),[519] were thought to confer invisibility upon the wearer. This inscription occurs on the hoop of a gold ring set with an uncut diamond, shown at the Special Exhibition at the South Kensington Museum, June, 1862. This motto, “Jesus autem transiens,” etc., was in mediæval times regarded as a great charm against the dangers that menaced a traveller on his journeys. In his quaint old English, Sir John Mandeville says of this that these words were sometimes pronounced by “some men when thei dreden them of thefes on any way, or of enemyes, in token and mynde that our Lord passed through out of the Jews’ crueltie and scaped safely fro hem.” On the gold noble which Edward III had struck in commemoration of his victory in the naval battle of Helvoet Sluys in 1340, and of his escape from the perils he underwent therein, this motto appears as the legend.[520]