| In this
exhibit there are six individual rods, each of which has been cut
in a special way. When plucked, each rod vibrates in a unique pattern.
They are squared off near the bottom and in some cases are thicker
on one side than the other. The ratio of these two thicknesses determines
the pattern of the vibration. When a rod is plucked it moves along
two different axes and at two different rates to form its special