The two great rivers unite at Apamea, or Corna (one hundred miles from the Persian Gulf), into the broad stream of the Pasitigris, or Shat-ul-Arab. The Euphrates formerly reached the sea by a separate channel, which was obstructed and diverted by the citizens of Orchoe, about twenty miles to the south-east of modern Basra (D'Anville, in the Memoires de l'Acad. des Inscriptions, tom. xxx.p. 170-191).