Small steamers have descended its entire course from Bir to the sea.

The volume of the Euphrates in places is, however, somewhat less than that of the Tigris, which is a swifter and in its latter course a deeper stream.

It has been calculated that the quantity of water discharged every second by the Tigris at Baghdad is 164,103 cubic feet, while that discharged by the Euphrates at Hit is 72,804 feet.
The Tigris and Euphrates are very differently circumstanced with respect to tributaries.

So long as it runs among the Armenian mountains, the Euphrates has indeed no lack of affluents; but these, except the Kara Su, or northern Euphrates, are streams of no great volume, being chiefly mountain-torrents which collect the drainage of very limited basins.
After it leaves the mountains and enters upon a low country at Sumefsat, the affluents almost entirely cease; one, the river of Sajur, is received from the right, in about lat.

36 deg.