The Sinjar range, which divides Western Assyria into two plains, a northern and a southern, is a solitary limestone ridge, rising up abruptly from the flat country, which it commands to a vast distance on both sides.  The limestone of which it is composed is white, soft, and fossiliferous; it detaches itself in enormous flakes from the mountain-sides, which are sometimes broken into a succession of gigantic steps, while occasionally they present the columnar appearance of basalt.  The flanks of the Sinjar are seamed with innumerable ravines, and from these small brooks issue, which are soon dispersed by irrigation, or absorbed in the thirsty plains.  The sides of the mountain are capable of being cultivated by means of terraces, and produce fair crops of corn and excellent fruit; the top is often wooded with fruit trees or forest-trees.  Geographically, the Sinjar may be regarded as the continuation of that range of hills which shuts in the Tigris on the west, from Tekrit nearly to Mosul, and then leaving the river strikes across the plain in a direction almost from east to west as far as the town of Sinjar.  Here the mountains change their course and bend to the south-west, till having passed the little lake described above, they somewhat suddenly subside, sinking from a high ridge into low undulating hills, which pass to the south of the lake, and then disappear in the plain altogether.  According to some, the Sinjar here terminates; but perhaps it is best to regard it as rising again in the Abd-el-aziz hills, which, intervening between the Khabour and the Euphrates, run in the same south-west direction from Arban to Zelabi.  If this be accepted as the true course of the Sinjar, we must view it as throwing out two important spurs.  One of these is near its eastern extremity, and runs to the south-east, dividing the plain of Zerga from the great central level.  Like the main chain, it is of limestone; and, though low, has several remarkable peaks which serve as landmarks from a vast distance.  The Arabs call it Kebritiyeh, or “the Sulphur range,” from a sulphurous spring which rises at its foot.  The other spur is thrown out near the western extremity, and runs towards the north-west, parallel to the course of the upper Khabour, which rises from its flank at Ras-el-Ain.  The name of Abd-el-aziz is applied to this spur, as well as to the continuation of the Sinjar between Arban and Halebi.  It is broken into innumerable valleys and ravines, abounding with wild animals, and is scantily wooded with dwarf oak.  Streams of water abound in it.

South of the Sinjar range, the country resumes the same level appearance which characterizes it between the Sinjar and the Mons Masius.  A low limestone ridge skirts the Tigris valley from Mosul to Tekrit, and near the Euphrates the country is sometimes slightly hilly; but generally the eye travels over a vast slightly undulating level, unbroken by eminences, and supporting but a scanty vegetation.  The description of Xenophon