Stationary wave patterns produced in metal or glass plates. Vibrations of plates can be set up by stroking the edge with a violin bow. It was shown in 1787, in experiments by the German lawyer and physicist Ernst F. F. Chladni (1756–1827), that the vibrations of plates could be made visible by sprinkling sand on the plate before applying the bow to it. Salt can also be used to illustrate vibrations in plates with the particles accumulating in drifts at nodes and moving away from antinodes. The nodes thus appear as white lines. The vibrations associated with these patterns are also associated with sounds given off by these plates (an example of this being a drumhead).