The Touz-Ghieul is a basin of a very different character. Situated on the upland of Phrygia, in lat. 39°, long. 33°, 30’, its elevation is not more than 2500 feet. Low hills of sandstone and conglomerate encircle it, but generally at some distance, so that a tract of plain, six or seven miles in width, intervenes between their base and the shore. The shape of the lake is an irregular oval, with the greater axis running nearly due north and south. Its greatest length is estimated at forty-five miles, its width varies, but is generally from ten to sixteen miles. At one point, however, nearly opposite to Kodj Hissar, the lake narrows to a distance of no more than five miles; and here a causeway has been constructed from shore to shore, which, though ruined, still affords a dry pathway in the summer. The water of the Touz-Ghieul is intensely salt, containing at some seasons of the year no less than thirty-two per cent of saline matter, which is considerably more than the amount of such matter in the water of the Dead Sea. The surrounding plain is barren, in places marshy, and often covered with an incrustation of salt. The whole scene is one of desolation. The acrid waters support no animal organization; birds shun them; the plain grows nothing but a few stunted and sapless shrubs. The only signs of life which greet the traveller are the carts of the natives, which pass him laden with the salt that is obtained with ease from the saturated water.
The Zerreh or Sea of Seistan—called sometimes the Hamun, or “expanse”—is situated in the Seistan Desert on the Great Iranic plateau, and consequently at an elevation of (probably) 3000 feet. It is formed by the accumulation of the waters brought down by the Helmend, the Haroot-rud, the river of Khash, the Furrah-rud and other streams, which flow from the mountains of Afghanistan, with converging courses to the south-west. It is an extensive basin, composed of two arms, an eastern and a western. The western arm, which is the larger of the two, has its greatest length from N.N.E. to S.S.W., and extends in this direction about ninety miles. Its greatest width is about twenty-five miles. The eastern arm is rather more than forty miles long, and from ten to twenty broad. It is shaped much like a fish’s tail. The two arms are connected by a strait seven or eight miles in width, which joins them near their northern extremities. The water of the lake, though not salt, is black and has a bad taste. Fish support life in it with difficulty, and never grow to any great size. The lake is shallow, not much exceeding a depth of three or four feet. It contracts greatly in the summer, at which time the strait connecting the two arms is often absolutely dry. The edges of the lake are clothed with tamarisk and other trees; and where the rivers enter it, sometimes by several branches, the soil is rich and cultivation productive; but elsewhere the sand of the desert creeps up almost to the margin of the water, clothed only with some sickly grass and a few scattered shrubs.
The Birket-el-Keroun, or Lake Moaris of the classical writers, is a natural basin—not, as Herodotus imagined, an artificial one—situated on the western side of the Nile valley, in a curious depression which nature has made among the Libyan hills. This depression—the modern district of the Faioom—is a circular plain, which sinks gradually towards the north-west, descending till it is more than 100 feet below the surface of the Nile at low water. The Northern and northwestern portion of the depression is occupied by the lake, a sheet of brackish water shaped like a horn (whence the modern name) measuring about thirty-five or thirty-six miles from end to end, and attaining in the middle a width of between five and six miles. The area of the lake is estimated roughly at 150 square miles, its circumference at about ninety miles. It has a depth varying from twelve to twenty-four feet. Though the water is somewhat brackish, yet the Birket contains several species of fresh-water fish; and in ancient times its fisheries are said to have been exceedingly productive.
The principal cities of the Empire were, besides Pesargadae and Persepolis, Susa—the chief city of Susiana—which became the capital; Babylon, Ecbatana, Rhages, Zadracarta, Bactra (now Balkh), Maracanda (now Samarcand), Aria, or Artacoana (Herat), Caspatyrus on the Upper Indus,Taxila (Attock?), Pura (perhaps Bunpoor), Carmana (Kerman), Arbela, Nisibis, Amida (now Diarbekr); Mazaca in Cappadocia; Trapezus (Trebizond), Sinope, Dascyleium, Sardis, Ephesus, Miletus, Gordium, Perga, and Tarsus in Asia Minor: Damascus, Jerusalem, Sidon, Tyre, Azotus or Ashdod, and Gaza in Syria; Memphis and Thebes in Egypt; Cyrene and Barca in the Cyrenaica. Of these, while Susa had from the time of Darius Hystaspis a decided pre-eminence as the main residence of the court, and consequently as the usual seat of government, there were three others which could boast the distinction of being royal abodes from time to time, either regularly at certain seasons, or occasionally at the caprice of the monarch. These were Babylon, Ecbatana, and Persepolis, the capitals respectively of Chaldaea, Media, and Persia Proper, all great and ancient cities, accustomed to the presence of Courts, and all occupying positions sufficiently central to render them not ill-suited for the business of administration. Next to these in order of dignity may be classed the satrapial residences, often the chief cities of old monarchies, such as Sardis, the capital city of Lydia, Dascyleium of Bithynia, Memphis of Egypt, Bactra of Bactria, and the like; while the third rank was held by the towns, where there was no Court, either royal or satrapial.
Before this chapter is concluded a few words must be said with respect to the countries which bordered upon the Persian Empire. The Empire was surrounded, for the most part, either by seas or deserts. The Mediterranean, the Egean, the Propontis, the Euxine, the Caspian, the Indian Ocean, the Persian Gulf, and the Arabian Gulf or Bed Sea washed its shores, bounding almost all its western, and much of its northern and southern sides; while the sands of the Sahara, the deserts of Arabia and Syria of India and Thibet, filled up the greater part of the intervening spaces. The only countries of importance which can be viewed as in any sense neighbors of Persia are European and Asiatic Scythia, Hindustan, Arabia, Ethiopia, and Greece.
Where the Black Sea, curving round to the north, ceased to furnish to the Empire the advantage of a water barrier, a protection of almost equal strength was afforded to it by the mountain-chain of the Caucasus. Excepting on the extreme east, where it slopes gently to the Caspian, this range is one of great elevation, possessing but few passes, and very difficult to traverse. Its fastnesses have always been inhabited by wild tribes, jealous of their freedom; and these tribes may have caused annoyance, but they could at no time have been a serious danger to the Empire. They were weak in numbers, divided in nationality and in interests, and quite incapable of conducting any distant expedition. Like their modern successors, the Circassians, Abassians, and Lesghians, their one and only desire was to maintain themselves in possession of their beloved mountains; and this desire would cause them to resist all attempts that might be made to traverse their country, whether proceeding from the north or from the south, from the inhabitants of Europe or from those of Asia. Persia was thus strongly protected in this quarter; but still she could not feel herself altogether safe. Once at least within historic memory the barrier of the Caucasus had proved to be surmountable. From the vast Steppe which stretches northwards from its base, in part salt, in part grassy, had crossed into Asia—through its passes or round its eastern flank—a countless host, which had swept all before it, and brought ruin upon flourishing empires. The Scythian and Samaritan hordes of the steppe-country between the Wolga and the Dnieper were to the monarchies of Western Asia a permanent, if a somewhat distant, peril. It could not be forgotten that they had proved themselves capable of penetrating the rocky barrier which would otherwise have seemed so sure a protection, or that when they swarmed across it in the seventh century before our era, their strength was at first irresistible. The Persians knew, what the great nations of the earth afterwards forgot, that along the northern horizon there lay a black cloud, which might at any time burst, carrying desolation to their homes and bringing ruin upon their civilization. We shall find the course of their history importantly affected by a sense of this danger, and we shall have reason to admire the wisdom of their measures of precaution against it.
It was not only to the west of the Caspian that the danger threatened. East of that sea