All this drainage, collected into two rivers, the Belikh and the Khabur, is towards the left bank of the Euphrates, for the Mesopotamian watershed seems to be only some 15 m.
When Khammurabi's fifth successor saw the fall of the Amorite dynasty in consequence of an inroad of "Hittites," these may have been Mesopotamian Shubaru-Mitanni; but they may, as Ungnad suggests, represent rather an- Timee Times.
Knowing what we know of the colonizing power of the Assyrians, we may assume that among the "Mitanni" and other elements in the Mesopotamian population there would now be an increase of people of "Assyrian" origin.
On the Mesopotamian side there would seem, from the accounts of Xenophon and Ptolemy, to have been an affluent which joined the Euphrates between Deir and `Ana, called Araxes by the former, Saocoras by the latter; but no trace of such a stream has been found by modern explorers and the country in general has always been uninhabited.
The southern and south-western face follows the coast closely up the Persian Gulf from the mouth of the Indus, and is formed farther west by the mountain scarp, which, rising in many points to 10,000 ft., flanks the Tigris and the Mesopotamian plains, and extends along Kurdistan and Armenia nearly to the 40th meridian; beyond which it turns along the Taurus range, and the north - eastern angle of the Mediterranean.