Move the lever from the left to the right multiple times and let go. Observe what happens. Due to the movement of the spiral spring you can observe the formation of transverse waves. Although you move the lever horizontally from the left to the right a wave moves forward through the spring and then comes back.
Further informationson the exhibit "Spiral Spring"
In addition, depending on the stimulation of the spiral, different wave motions can be visible. For example the fundamental mode with only one loop.
Comparable waves are for example light waves.