‎"LISSAJOUS, (JULES ANTOINE). - THE ""LISSAJOUS FIGURES"" AND THE ""PHONOPTOMÈTRE""‎
‎Mémoire sur l'Étude optique des Mouvements vibratoires. Mémoire présenté à l'Academie des Sciences dans la séance du 6 avril 1857.‎

‎Paris, Victor Msson, 1857. 8vo. Contemp. hcalf, raised bands, gilt spine. Light wear along edges. Small stamps on verso of titlepage. In: ""Annales de Chimie et de Physique"", 3e Series - Tome 51. 512 pp. a. 2 folded engraved plates. Small stamp to verso of plates. (The entire volume offered). Lissajous paper: pp. 147-231 a. 2 large folded engraved plates showing his experimental apparatus, his Phonoptomètre and the curves.‎

Reference : 44169

‎First appearance of Lissajous's most substantiel paper in which he describes his experimental technique by which he, together with Helmholtz, founded the modern sound theory. His invention of the Phonoptomètre, a vibratingmicroscope in which a tuning fork is attached to the objective lens, is also described and depicted on the plate.""Lissajous developed an optical method for studying vibration and was generally interested in the physics of wave motion. ""Lissajous igures"" are the curves in the xy plane generated by the functions y=a sin( (w1t + q1) and x=b sin (w2t + q2), where w1 and w2 are small integers. The curves are today easily produced on an oscilloscope screen"" but Lissajous obtained them in the context of acoustics, from the superposition of the vibrations of the tuning forks....The French physicists awarded the Lacaze Prize to Lissajous for his ""beautiful experiments"" and both Rayleigh and Tyndall discussed his work in their treatises on sound.""(DSB VIII, pp. 398-99.).‎