(under the class definition) Amusement device either (a) comprising the surface of a room, hallway, or other passageway over which a person may walk and wherein at least a portion of the surface rotates, reciprocates, vibrates, collapses, or otherwise moves beneath the feet of the person so as to make walking over the surface difficult for the person; or (b) comprising a series of steps forming a stairway over which a person may walk and wherein at least one of the treads or at least a portion of a tread of the stairway vibrates, collapses under the weight of the person, or otherwise moves beneath the feet of the person so as to make walking up or down the stairway difficult for the person.
65, for a floor or floor section of a building which is rotatable about a vertical axis, subclass 71 for a building floor structure composed of hingedly connected sections, subclass 183 for a building stair structure composed of interconnected, relatively movable components, and subclasses 184+ for a building stair structure with an additional building feature.
