This was our last complete prospect over that great depression which is known as the plain of Mush. [164] We proceeded at half-past two, and rode at a trot over the plateau, first on a northerly and then on a north-easterly course. The rock appeared to be of an eruptive volcanic description. By half-past four we arrived upon the opposite margin, where the ground abruptly sank to a wide trough of broken country, with a small plain, level as water, at its western end. We ascertained that this fresh depression had an elevation of about 5000 feet, or a difference in height of 3000 feet from the pass at which we measured that of the plateau. On the further side rose a cliff of such gigantic proportions that, when we reached the middle slopes of the descent into the hollow, it reminded me of the landscape in the narrows of the Araxes, with those cliffs raised to double their size. From a distance we had wondered at the strange appearance of this flat-edged mass, which seemed to embrace us in a wide segment with precipitous sides. A nearer view disclosed the direction it was pursuing, and enabled us to trace, although in a most imperfect manner, its connection with the orography of the eastern districts. That direction was approximately latitudinal, but inclined a little towards the south. The further east the mass proceeded, the more it lost its cliff-like character, the nearer it approached to the characteristics of a mountain range. In this form it was protracted to dimly visible limits, joining the distant outlines of Sipan. I had read many accounts of the famous Bingöl Dagh, the parent mountain of the Araxes and of the principal tributaries of the Euphrates, and, in some sense, the roof of Western Asia. None had prepared me for the vision before our eyes. The actual walls of the crater were not, I imagine, visible; but those cliffs had no doubt been covered by deep beds of lava which had added to their height. The greatest eminence on the extinct volcano is that of Demir-Kala, which must be situated not far from the edge of the cliff. It has an elevation of 10,770 feet. [165] But the mountain proper is but a wart on the face of the lofty tableland from which it rises, and which it has contributed to shape. I tried to examine the relation of this tableland to the plateau which we had crossed, but was prevented by the lie of the land upon the west.