The appartus for the optical study of sound is always given the name of the Lissajous apparatus since it was designed by Jules Antoine Lissajous (1822-1880), a professor at the Saint-Louis Lycée in Paris. He described it in a Paper presented to the Academy of Sciences in Paris at the meeting held on 6 April 1857 and published in Volume LI of the Annales de Chimie et de Physique of the same year.
The apparatus for the graphic study is also the merit of Paul Desains, a professor of Physics at the University of Paris, and is known as the Lissajous and Desains apparatus.
The merits of each in creating these instruments and in the contribution made by their having built the prototypes are described by Lissajous himself in the paper presented to the Academy, in which he states that he had been stimulated in his study of a way to make the oscillatory movements of vibrating bodies visible without recourse to mechanical traces, by the effectiveness of the methods of projection in teaching acoustics, methods that Paul Desains frequently used in his courses.
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