The ridges, frequently four, five, or even six in number, run in the direction of the whole range, and are frequently united by transverse ridges. But there are also some valleys in the southern part of the system which run across the ranges, as is evident from the courses of the rivers; for nearly all those rivers which join the Tigris south of 30° N. 1st, and traverse this mountain region, do not rise within tho range, but to the east of it, on the plains of the table-land of Iran, such as the Great Zab, the Diyalah, and the Kerkhah. Several summits and ridges attain a great elevation, being for nine or ten months covered with snow; two summits of the Kurdistan Mountains rise above the suow-line: one on the most western ridge called Kebir-Koh, near 33° 15' N. lat, and the other in the ridge, called Koh-Mungasht, near 31° 25' N. lat.
That part of the great plain traversed by the Euphrates and Tigris, which belongs to Persia, lies between the mountains of Kurdistan, and the banks of the Tigris and Shat-el-Arab. It is about 100 miles long, and, on the average, 30 miles wide. The lower portion of it, which lies along the great river, and comprehends nearly one-half of the country, is swampy and uninhabited. About fifteen miles from the banks of the river, the country is considerably higher, but as the soil is composed partly of sand and partly of a hard clay, it cannot be cultivated, except along the banks of the rivers, and even there culti vation is very limited. The greater part of the country is a waste, which does not yield pasture, except for camels. This more elevated tract is called Chad, or Kaaba= The country which lies east of the Kurdistan Mountains, and between them and the Kuweer, or Salt Desert, belongs to the table-land of Iran. Its general elevation above the sea in the southern districts exceeds 4000 feet, and rises in some parts to 6000 feet ; but north of Ispahan it sinks down to 2500 feet, and in some places even lower. It is a plain traversed by numerous ridges of rocky hills, which generally run from west to east, and sink gradnally into the desert farther east. Few of these hills are more than 1000 feet above their base, and gene rally not half so mach. The valleys are open and wide, in some parts exceeding ten or fifteen miles in width; they are also very long. Here too, as in most places on the table-land of Iran, cultivation is limited for want of water. As the eastern ridge of the Kurdistan Mountains does not rise high enough to be covered with snow for many mouths, the rivers which descend from them are scarcely provided with water during a groat part of the year; and the little that they furnish is absorbed in irrigation. The valleys are consequently, for the most part, uncultivated, except iu the vicinity of the villages.
The mountain region of Faraistan and Kerman occupies the whole of Persia south of 30° N. lat., from the mouth of the river Tab to Cape Jest (from 50° to E. long.), a distance of nearly 500 miles in length, and nearly 200 miles in average width. On the south it is washed by the Persian Gulf, and on the north-it borders on the desert of Kerman. Along the shores of the gulf is a low and sandy tract, varying in width from 20 to 30 miles, the soil of which is impregnated with salt, and produces little else than dates. This district, which has a very warns climate, is called Dushtistan or Guru:lair, that is, 'warm region.' At the back of this low tract the country rises in steep and bare rocks to the height of mountains, and constitutes an elevated region which extends more than 100 miles inland, where it stretches out in a plain traversed by low rocky ridges running east and west. About 50 miles from the sea, the lowest part of the moun tainous tract ie about 2500 feet above the sea-level, but where it approaches the plain it attains the height of 4000 feet. This moun tainous region is called Sirhud (the cold country), in opposition to Gurmair. In its northern districts, where it is connected with the mountains of Kurdistan, the rocky ridges, which traverse the surface longitudinally from west to east, rise to 7000 or 8000 feet, and in these parts they are partially wooded. But south of 29° N. lat. they do not appear to attain so great an elevation, rising probably only from 1000 to 2000 feet above their base, which in many places cannot attain a great elevation above the sea, as the valleys inclosed by the ridges produce the date. The ridges, though generally of inconsi derable width, are numerous, and the valleys are narrow, except towards the north, where they are from 15 to 20 miles across. The mountains are barren and destituts of vegetation, but the valleys are rich in fruits, and even grain, where they can be irrigated. The plain which extends along the northern aide of the mountain region, and which is from 60 to 100 miles in width, has a soil strongly im pregnated with salt, and contains several smaller salt lakes, besides the great salt lake of Bakhtegan. It would form a portion of the Great Desert, if it were not divided from it by a series of oases, which stretch east and west through it, between 29° and 30° N. lat., and which are inclosed on the north and south by two low ridges of rocky hills. This narrow fertile tract, called the Nurmanshtr, produces some grain, but it is particularly rich in several kinds of fruit, which attain great perfection.