Most wave motion takes place at frequencies too high to follow easily with the eye. Dr. John N. Shive, a Bell Laboratories scientist, developed this device to demonstrate slow-motion transverse waves. Steel rods at close intervals are joined by a thin torsion wire. The torsion wire transmits energy from one rod to the next. Because of the high moment of inertia of the rods, a disturbance takes several seconds to travel from one end of the array to the other. The transverse motion of the ends of the rods can clearly show wave reflection, standing waves, resonance, partial reflection, and impedance matching. At our exhibit a visitor can generate waves at one end of a torsion line with a motor-driven crank. The visitor turns a knob to vary the motor speed, thereby changing the frequency of the waves. A frequency meter indicates the frequency. The visitor can also push a button to generate a single pulse.