The northern mountain country--known to modern geographers as Eiburz--is a tract of far less importance. It is not composed, like Zagros, of a number of parallel chains, but consists of a single lofty ridge, furrowed by ravines and valleys, from which spurs are thrown out, running in general at right angles to its axis. Its width is comparatively slight; and instead of giving birth to numerous large rivers, it forms only a small number of insignificant streams, often dry in summer, which have short courses, being soon absorbed either by the Caspian or the Desert. Its most striking feature is the snowy peak of Demavend, which impends over Teheran, and appears to be the highest summit in the part of Asia west of the Himalayas. The elevated plateau which stretches from the foot of those two mountain regions to the south and east is, for the most part, a flat sandy desert, incapable of sustaining more than a sparse and scanty population. The northern and western portions are, however, less arid than the east and south, being watered to some distance by the streams that descend from Zagros and Elburz, and deriving fertility also from the spring rains. Some of the rivers which flow from Zagros on this side are large and strong. One, the Kizil-Uzen, reaches the Caspian. Another, the Zenderud, fertilizes a large district near Isfahan. A third, the Bendamir, flows by Persepolis and terminates in a sheet of water of some size--lake Bakhtigan. A tract thus intervenes between the mountain regions and the desert which, though it cannot be called fertile, is fairly productive, and can support a large settled population. This forms the chief portion of the region which the ancients called Media, as being the country inhabited by the race on whose history we are about to enter. Media, however, included, besides this, another tract of considerable size and importance. At the north-western angle of the region above described, in the corner whence the two great chains branch out to the south and to the east, is a tract composed almost entirely of mountains, which the Greeks called Atropatene, and which is now known as Azerbijan. This district lies further to the north than the rest of Media, being in the same parallels with the lower part of the Caspian Sea. It comprises the entire basin of Lake Urumiyeh, together with the country intervening between that basin and the high mountain chain which curves round the south-western corner of the Caspian, It is a region generally somewhat sterile, but containing a certain quantity of very, fertile territory, more particularly in the Urumiyeh basin, and towards the mouth of the river Araxes.