text: Eugène-Anatole Demarçay was born to  Camille Demarçay (1815–1893) and Cécile Lainé (1829–1916) at 152 Haussman, Paris. His grandfather Marc-Jean Demarçay (1772–1839) had been a general in the French Revolution. ). Demarçay studied at the Lycée Condorcet, spent time in England, and in 1870 entered the École Polytechnique in Palaiseau near Paris. Demarçay studied under Jean Baptiste Dumas (1800–1884) and served for several years as an assistant to Auguste André Thomas Cahours at the École Polytechnique. In 1876, he studied acetylacetonates in the laboratory of Cahours. He spent some years travelling to Egypt and India. In 1880 he completed his dissertation, Sur les acides tétrique et oxytétrique et leurs homologues ("On tetric and oxytetric acids and their counterparts" Gauthier-Villars, 1880). Some of his early organic chemistry researches into terpenes and ether were important for the perfume industry.