The deserts of this region between the Indus and Tigris are in a measure connected with its water system. They present vast tracts of elevated sandy wastes, perfectly void of water and vegetation except on their skirts. Each division of the region has a desert of its own. That of Persia has been before mentioned as stretching north and south across the eastern portion of that country. The desert of Afghanistan extends east and west across the western half of its southern border, from the highlands of Calát to the mountains of Sarhadd, south of Sistan. It is called the Regi Sistan or Regi Balochistan—the sands of Sistan or Balochistan—and extends from the Mushti range of mountains on the south up to the plain of Kandahar on the north, where it ends in a high coast of desert cliffs. This elevated border is called _chol_, or “dry land,” and forms a belt ten or fifteen miles wide, on which is found a rich winter pasture for the cattle of the nomads who here make their winter quarters. There is also a desert tract to the north between the Caspian and Oxus; but it differs from the deserts of Persia and Afghanistan in an important particular. Its surface is a firm gravel, broken into undulations, and covered with a more or less rich pasture of aromatic herbs, and water is found in some of the hollows on its surface. The plains of this region are all elevated plateaux of greater or less extent, and more frequently the latter. They are all covered with excellent pastures of rich aromatic herbs and hardy plants, and are the natural home of the asafœtida and wormwood, and, in the more elevated tracts, of the rhubarb. Most of them are watered by brisk little hill-streams, or by those artificial subterranean conduits called _kárez_, and are more or less populous; villages, fruit-gardens, and cultivation following the course of the streams, and nomad camps covering the pastures during the summer months. In Balochistan, these plateaux rise in steps one above the other between the hills up to the tableland of Calát. North of this they fall in steps to the Kandahar plain, which itself sinks towards the south-west to the Sistan basin. In Persia they rise in a similar gradation from the shores of the Persian Gulf and basin of the Tigris up to the tablelands of the interior, where they sink again gradually to the lowest part of the salt desert in the south-east portion of the country. Such, in general terms, are the main features of the region between the Indus and the Tigris. Its climate, as may be imagined, is as varied as the surface of the country. It partakes of the temperate character of an Alpine climate in the northern mountain tracts, whilst in the lower desert tracts it equals in heat the torrid plains of India during the summer months. But in winter it is everywhere cold; in the mountain regions rigorously so, whilst on the wide plains and deserts it is equally severe by reason of the strong north winds that sweep the country for months.