A very interesting study and book.
In 1967, Jenny published the first volume of Cymatics: The Study of Wave Phenomena. The second volume came out in 1972, the year he died. This book was a written and photographic documentation of the effects of sound vibrations on fluids, powders and liquid paste. He concluded, “This is not an unregulated chaos; it is a dynamic but ordered pattern.”
Jenny made use of crystal oscillators and his so-called tonoscope to set plates and membranes vibrating. He spread quartz sand onto a black drum membrane 60 cm in diameter. The membrane was caused to vibrate by singing loudly through a cardboard pipe, and the sand produced symmetrical Chladni patterns, named after Ernst Chladni, who had discovered this phenomenon in 1787. Low tones resulted in rather simple and clear pictures, while higher tones formed more complex structures.
Check out this video:
Cymatics Video