Stossmechanik

Stossmechanik (Ger.), an early piano action in which the hammer was hinged to a rail (hammer rail) attached to the key frame: the hammers pointed to the back of the instr. and were set in motion by a jack or other device fixed to the key. A simplified form of Cristofori's action, without escapement (92). Harding, Rosamund E. M. The Pianoforte. Cambridge, 1933.