the proprietor could keep the weight from going all the way to the top, but I never found out how he could do it

I read somewhere a while back that there was a lever or foot-pedal the carnie could press that subtly altered the tension of the wire going up to the bell. If the wire was taut, the projectile ascended to the top smoothly and easily. If it was loose, the energy of the strongest hammering was easily dampened, and inadequate for the task...