In 1802, the first attempt to seriously increase the volume of water supplied the city was made by drawing on the little river Ourcq. This canal brings a supply to the Bassin de la Villette, which serves as a reservoir to distribute it through Paris by means of the aqueduct of the Ceinture and large mains. The necessity of securing a larger supply, and a much purer one, was strongly felt by Baron Haussmann, who did so much for the embellishment of the city during the Second Empire, and in conjunction with the Engineer-in-chief of the navigation of the Seine, M. Belgrand, the present system was inaugurated. The latter found means of solving the problem after a careful study, in 1854, of the basin of the Seine. The bed of gypsum on which Paris is built furnishes neither water of a good drinking quality nor sources high enough to bring it into the city at the requisite altitude; it was therefore necessary to go outside this basin, extending from Meulan to Château-Thierry. At present, Paris is furnished with potable water by three aqueducts,--that of the Dhuis, a hundred and thirty-one kilomètres in length, constructed from 1862 to 1865, running from a source nearly due east of the city; that of the Vanne, a hundred and eighty-three kilomètres, 1866-1874, from the southeast, and that of the Avre, a hundred and eight kilomètres, 1890-1893, from the west. A fourth is to be built, of a length of seventy-two kilomètres, which will draw its supply from the valley of the Loing and the Lunain, a little west of Vanne.