"Differentiation, by compound negative vibration of their neutral centres, causes antagonism, and thus the great attractive power that aggregates them becomes one of dispersion or expansion, accompanied by immense velocity of rotation, which carries its influence through the whole volume of air, 230 cubic inches contained in sphere, within its 33 1/3 chord of its circle of coincidence. By this wire of platinum and silver the current of force is now passed to run the vibratory disk, thus altogether upsetting the "compressed air" theory of Professor Barkes, Dr. Hall, and others of less note." [Keely, Keely and His Discoveries]
See Also
Chladni wave plate
Cymatics
Harmonic Vibrations and Vibration Figures
Harmonograph
Holographic Interferometry
Law of Corporeal Vibrations
Law of Harmonic Vibrations
Principles of Acoustics
resonating plates
Schlieren photography
Table of Plate Harmonics and Intervals
Visible Sound
Wave Plate