[Set of 19th century Scientific and Mathematical Treatises], together 11 vol., comprising: Avogadro (Amedeo) Fisica de' Corpi Ponderabili..., 4 vol., first edition, half-titles, 18 folding lithographed plates, Turin, 1837-41 § Cauchy (Augustin Louis) & others. Opuscoli Matematici Fisici di Diversi Autori, 2 vol. in 1, first edition, 2 folding plates, Milan, 1832-34 § Cauchy (Augustin Louis) "Mémoire sur la Dispersion de la Lumière", in Nouveaux Exercices de Mathématiques, browning heavy at points, Prague, 1835-36 § Legendre (Adrien Marie) Traité des Fonctions Elliptiques et des Intégrales Eulériennes, 3 vol., first edition, half-titles, 4 folding plates, lacking portrait of Euler, Paris, 1825-28[-32] § Monge (Gaspard) Géométrie Descriptive, fifth edition, half-title, 28 folding plates, occasional damp-staining to head, mainly to preliminaries, Paris, 1827 § Prony (Gaspard de) Leçons de Mécanique Analytique..., 2 parts in 1, first edition, half-titles, 4 folding plates, some damp-staining to plates, Paris, 1810-15, most plates tipped onto blank leaf at fore-edge, some browning and scattered foxing, generally light but heavier at points, similarly bound in contemporary half vellum (7 vol.) or full vellum (4 vol.), spines gilt and with morocco labels, some light toning or dust-soiling to vellum, some light wear to extremities, 4to & 8vo.

*** An attractive set of important 19th century scientific and mathematical treatises. The first mentioned is the first edition of Avogadro's magnum opus, containing his most important hypothesis, which established a method for distinguishing between atoms and molecules in a gas. Based on his hypothesis, it was possible to arrive at a constant that determined the number of molecules in a mole (a unit of measurement of the amount of a substance). Years after his death, this number was named the 'Avogadro number' in his honor.

The third mentioned contains Cauchy's famed equation, which determined the relationship between the wavelength of light and the refractive index of a material the light passes through. It is a continuation and expansion of his earlier work, of the same title, published in Paris in 1830, the earlier publication numbering 24pp. as opposed to 236pp.

The fourth mentioned is the rare first edition of Legendre's great work on the theory of elliptic functions, its application to geometry and mechanics, methods of constructing elliptical tables, Eulerian integrals, etc. This copy is complete with the three supplements published successively in 1828, 1829 and 1832.