sentences:  After having graduated with the highest honors at the École Polytechnique and École des Ponts et Chaussées, he was attached as engineer to the Southern Railroad; and under his direction the lines from Tech to Rivesaltes and from Tet to Perpignan were built, including the remarkable viaduct of Bouzanne.Afterward Carvallo became director of the work of canalizing the Ebro (Spain); and he established in the delta of that river a system of irrigation which permitted the cultivation of enormous tracts of land hitherto unproductive.From Spain Carvallo went to Italy, where he directed the works of the Roman railroads.