Owing to these natural "locks," the Senegal never discharges less than 1700 or 1800 cubic ft.
It receives many streams, and discharges at the south-western extremity by the Ericht.
Long, formed by the confluence of the Tercero and Cuarto, whose sources are in the Sierra de Cordoba; it flows eastward across the pampas, and discharges into the Parana at Gaboto, about 40 m.
The Seine descends from the Langres plateau, flows northwest down to Mry, turns to the west, resumes its north-westerly direction at Montereau, passes through Paris and Rouen and discharges itself into the Channel between Le Havre and Honfleur.
There is no municipal water-supply, and the main drain of the city discharges into the lower pool of Siloam, which has become an open cesspit.