20', after receiving the river of Fyzabad, and then proceeds, first west and afterwards north-west, across the Great Kharesmian Desert to the Sea of Aral.

During the first 450 miles of its course, while it runs among the hills, it receives from both sides numerous and important tributaries; but from the meridian of Balkh those fail entirely, and for above 800 miles the Oxus pursues its solitary way, unaugmented by a single affluent, across the waste of Tartary, rolling through the desert a wealth of waters, which must diminish, but which does not seem very sensibly to diminish, by evaporation.

At Kilef, sixty miles north-west of Balkh, the width of the river is 350 yards; at Khodja Salih, thirty miles lower down, it is 823 yards with a depth of twenty feet; at Kerki, seventy miles below Khodja Salih, it is "twice the width of the Danube at Buda-Pesth," or about 940 yards; at Betik, on the route between Bokhara and Merv, its width has diminished to 650 yards, but its depth has increased to twenty-nine feet.

Finally, at Gorlen Hezaresp near Khiva, the breadth of the Oxus is so great that both banks are hardly distinguishable at the same time; but the stream is here comparatively shallow, ceasing to be navigable at about this point.

The present course of the Oxus from its rise in Lake Sir-i-Kol to its termination in the Sea of Aral is estimated at 1400 miles.