"The peculiar forms shown in the illustrations of this article and which I call Voice-Figures, have excited much interest since their recent discovery, exhibited in London, England, at the rooms of the Musical Association, the Royal Institution, The Royal Society and elsewhere."An excellent paper, with plates, revealing how a very simple easy-to-make device shows how sound and vibrations can be made visible by forming beautiful geometric patterns in lycopodium dust or similar light-weight powders. Hans Jenny used these techniques to create his now famous films about cymatics. From Century Magazine, May, 1891. 8.5" X 11"