"The existence of this river at no very remote period, and the truth of the legends which assert the ancient fertility of the lands through which it flowed, are attested by the ruins which everywhere overspread what is now an arid sandy waste. Throughout this tract are scattered mounds, marking the sites of cities and towns. And there are strongholds still remaining, in a very decayed state, which were places of importance at the time of the early Mahommedan invasions. Amongst these ruins are found not only the huge bricks used by the Hindus in the remote past, but others of a much later make. All this seems to show that the country must have been fertile for a long period . . ."