CAUCHY, Augustin-Louis. Mémoire sur les intégrales définies. [and] Mémoire sur la théorie de la propagation des ondes a la surface d'un fluide pesant, d'une profondeur indéfinie.
Paris: Académie Royale des Sciences, 1827. First edition.

First printing of these two classic memoires, originally written in 1814 and 1815, on the theory of complex functions and the propagation of waves. "In 1814 he submitted to the French Academy the treatise on definite integrals that was to become the basis of the theory of complex functions. In 1816 he won a prize contest of the French Academy on the propagation of waves at the surface of a liquid; his results are now classics in hydrodynamics." (DSB). The first memoire "was presented to Classe I of the Institute de France on 22 August 1814 ... [and] was examined by Legendre and Lacroix, and its publication was recommended in their report ... The original intention was that the memoire should appear in the Mémoires présentés à l'Institut des Sciences, Lettres et Arts, par divers savans, but no further issues of this periodical were published ... The first volume of the replacement periodical, the Mémoires présentés par divers savans à l'Académie Royale des Sciences de l'Institut de France, did not appear until 1827, and did contain both this memoire and Cauchy's prize essay (1815) on the theory of waves." (Smithies: Cauchy and the Creation of Complex Function Theory, p.24).

In: Mémoires présentés par divers savans à l'Académie Royale des Sciences de l'Institut de France, Vol. 1, pp. 3-312 [memoire on wave theory]; pp. 611-799 [memoire on complex function theory]; pp. 601-610 [Legendre's report ]. Large 4to: 257 x201 mm. Contemporary calf, finely re-backed. Engrvaed book plate of the Radcliffe Observatory, Oxford. Some light brown spotting to the first and last few leaves. In all a fine copy in a beautiful binding. (6), 799, (1:blank) pp.