Further to the east, beyond the low sandy plain, and beyond the mountains in which its great rivers have their source--on the other side of the “Roof of the World,” as the natives name this elevated region--lay a tract unimportant in itself, but valuable to the Persians as the home of a people from whom they obtained excellent soldiers. The plain of Chinese Tartary, the district about Kashgar and Yarkand, seems to have been in possession of certain Sacans or Scythians, who in the flourishing times of the empire acknowledged subjection to the Persian crown. These Sacans, who call themselves Huma-varga or Amyrgians, furnished some of the best and bravest of the Persian troops. Westward they bordered on Sogdiana and Bactria; northward they extended probably to the great mountain-chain of the Tien-chan; on the east they were shut in by the vast desert of Gobi or Shamoo; while southward they must have touched Gandaria and perhaps India. A portion of this country--that towards the north and west--was well watered and fairly productive; but the southern and eastern part of it must have been arid and desert. From this consideration of the Eastern provinces of the Empire, we pass on naturally to those which lay towards the North-West. The Caspian Sea alone intervened between these two groups, which thus approached each other within a distance of some 250 or 260 miles. Almost immediately to the west of the Caspian there rises a high table-land diversified by mountains, which stretches eastward for more than eighteen degrees between the 37th and 41st parallels. This highland may properly be regarded as a continuation of the great Iranean plateau, with which it is connected at its south-eastern corner. It comprises a portion of the modern Persia, the whole of Armenia, and most of Asia Minor. Its principal mountain-ranges are latitudinal or from west to east, only the minor ones taking the opposite or longitudinal direction. Of the latitudinal chains the most important is the Taurus, which, commencing at the southwestern corner of Asia Minor in longitude 29° nearly, bounds the great table-land upon the south, running parallel with the shore at the distance of sixty or seventy miles as far as the Pylse Cilicise, near Tarsus, and then proceeding in a direction decidedly north of east to the neighborhood of Lake Van, where it unites with the line of Zagros. The elevation of this range, though not equal to that of some in Asia, is considerable. In Asia Minor the loftiest of the Taurus peaks seem to attain a height of about 9000 or 10,000 feet. Further to the east the elevation appears to be even greater, the peaks of Ala Dagh, Sapan, Nimrud, and Mut Khan in the tract about Lake Van being all of them considerably above the line of perpetual snow, and therefore probably 11,000 or 12,000 feet.