BLACK JACK, a bludgeon-like weapon consisting of a lead slug attached to a leather thong. The more carefully con trived black jacks contain a spring within the handle which serves to ease the effect of the impact upon the wrist of the one who wields the weapon. The black jack has the reputation of being a characteristic weapon of urban gangsters and rowdies. In Eng land a black jack or black-jack was a big leather quart pot or drinking cup, often with a silver rim; see the conclusion of the song, "Simon the Cellarer": "But yo, ho, ho ! His nose doth show How oft the Black Jack to his lips doth go."