34 HISTORl OF GREECE. was on the opposite side of the river, at or near this point, a flour, ishing city named Charmande ; to which many of the soldiers right angles to the current, and carried various distances towards the inte- rior, from two hundred to one thousand two hundred yards. " But what most concerns the subject of this memoir is, the existence of A parapet wall or stone rampart in the river, just above the several aque- ducts. In general, there is one of the former attached to each of the latter And almost invariably, between two mills on the opposite banks, one of them crosses the stream from side to side, with the exception of a passage left in the centre for boats to pass up and down. The object of these sub- saqueous walls would appear to be exclusively, to raise the water sufficiently at low seasons, to give it impetus, as well as a more abundant supply to the wheels. And their effect at those times is, to create a fall in every part of the width, save the opening left for commerce, through which the water rushes with a moderately irregular surface. These dams were probably from four to eight feet high originally; but they are now frequently a bank of stones disturbing the evenness of the current, but always affording a suf- ficient passage for large boats at low seasons." The marks which Colonel Chesney points out, of previous population and industry on the banks of the Euphrates at this part of its course, arc extremely interesting and curious, when contrasted with the desolation depicted by Xenophon ; who mentions that there were no other inhabitants than some who lived by cutting millstones from the stone quarries near, and sending them to Babylon in exchange for grain. It is plain that the popu- lation, of which Colonel Chesney saw the remaining tokens, either had al ready long ceased, or did not begin to exist, or to construct their dams and aqueducts, until a period later than Xenophon. They probably began during the period of the Seleukid kings, after the year 300 B. c. For this line of road along the Euphrates began then to acquire great importance as the means of communication between the great city of Selcukeia (on the Tigris, below Bagdad) and the other cities founded by Seleukus Nikator and his successors in the North of Syria and Asia Minor Scleukeia in Pieria, Antioch, Laodikeia, Apameia, etc. This route coincides mainly with the present route from Bagdad to Aleppo, crossing the Euphrates at Thapsakus. It can hardly be doubted that the course of the Euphrates was better protected during the two centuries of the Seleukid kings (B.C. 300-1CC, speaking in round numbers), than it came to be afterwards, when that river became the boundary line between the Romans and the Parthians. Even at the time of the Emperor Julian's invasion, however, Ammianus Marcellinus describes the left bank of the Euphrates, north of Babylonia, as being in several parts well cultivated, and furnishing ample subsistence, (Ammian. Marc, xxiv, 1 ). At the time of Xenophon's Anabasis, there was nothing to give much importance to the banks of the Euphrates north of Babylonia.
