monkey board
n.— «The eager, quick-eyed, ragged-headed sprite, who, with the agility of a monkey or a London sparrow, skips about stand-still omnibuses, this side, that side, and hopping on and off the step behind, ever in danger of a kick from the conductor on his monkey board.» —“The London Street Boys” by James Greenwood New York Times Jan. 29, 1871. (source: Double-Tongued Dictionary)