society > leisure > the arts > music > musical instrument > keyboard instrument > organ > [noun] > stop-knob
stop1585
stop-handle1858
piston1873
stop-knob1887
piston knob1890
thumb-piston1904
speaking stop1938
1890 Salem (Ohio) Daily News 12 June The instrument contains 1, 867 pipes.., 18 pneumatic piston knobs, and 3 pedal combinations operating the entire organ.