The pass, or crest of the ridge (6870 feet), is close behind Demian. Among our landmarks, besides Sipan, the Akh Dagh was most conspicuous, and, although probably less lofty, because quite free from snow, dwarfed the intermediate mass of Khamur. The dome of the Kuseh Dagh was the bold feature of the scene in the north; while Kartevin rose like an island in the plain at our feet. This pass is but the edge of a deep block of hill country, interposed between the plain and the lake of Van. The highest level which we attained, during our passage across it, belonged to the ridge on the north of the village of Khanik, and was a level of 7690 feet. That ridge was composed of Eocene limestone, perhaps a travertine, while the ridge behind Demian displayed the familiar fossils of the widely-distributed lacustrine rocks. Coralline limestones of Eocene epoch, much altered and hardened, perhaps by the action of hot springs, constitute the backbone of the mass; while on its southern side the lacustrine series is represented by the purplish-brown sandstones of the hills behind Akhlat. Sipan has burst through the zone of limestone hills, probably about in the central region; the volcano has been built up upon their debris, and overtowers their almost uniform levels. Yet the stratified rocks are little diversified by volcanic outpourings: and only once, namely just upon our departure from the valley of Khanik, did we ride over such material, a dark volcanic tuff. It is indeed surprising, the limited extension of the flows of lava even from such a giant as Sipan. When we looked across to the mountain from the lofty down behind Demian, the block of hills appeared to compose an outer sheath to the volcano, recessing inwards around its contours. And the plain or pedestal of lava at the foot of Sipan was seen tonguing into the recess at our feet. Through that valley was winding a little stream, which would probably become lost in the plain. We descended into the valley, which supports several Kurdish villages, and rose up the opposite side. From this ridge to the guardhouse on the southern side of the block is the wildest portion of this bleak zone. We passed only one village, the Circassian settlement of Khanik, during our progress from the ridge to Akhlat. The axis or strike of the limestones is in an east-north-east direction; they are carved out into deep and irregular valleys.