On this table-land the heat is softened, though not entirely, by the elevation of the soil. After violent storms in the spring, no cloud darkens the sky from May to September; the atmosphere is peculiarly dry and clear, and through the fine air can be seen, bright and sharp, the outlines of the mountains and the whole country, while at night the star-lit sky almost replaces the light of day. The changes in temperature are sudden and severe. From cold, snow-covered terraces, 8000 feet in height, we suddenly descend to the glowing heat of the plains, lying barely 2000 feet above the sea. In the north-east oppressive heat alternates with great cold; the north suffers from a severe winter, with heavy falls of snow and icy storms, blowing over the Caspian Sea and the broad steppes; in the south the air is filled with the dust of the desert, here extraordinarily fine, and the hot winds give the heaps of sand the appearance of changing waves, and roll masses of it to the sky.[1] As far back as our information extends, we find the table-land of Iran occupied by a group of nations closely related to each other, and speaking dialects of the same language. On the edges of that great desert, which occupies the centre of the land, are tracts of pasture, and further inland, treeless steppes, which, however, are watered here and there by brackish pools, and produce a salt vegetation barely sufficient to provide buffaloes and camels with sustenance, until the soil becomes entirely barren. In the western part of these steppes wandered a pastoral people, whom Herodotus calls Sagartians. They were horsemen, but, according to the historian's statement, carried no weapons of attack beyond a dagger and a rope of twisted straps, at one end of which was a loop. In this they placed their confidence in battle; they threw it over men and horses, and so dragged them down and strangled them. In the inscriptions of the Achæmenids this nation is called _Açagarta_.[2]