The decadence of Babylon had begun when Herodotus visited it towards the middle of the fifth century before our era;[71] but the town was still standing, and some of the colossal works of its later kings were still intact. The last dynasty had come to an end less than a century before. We are ready, therefore, to believe the simple and straightforward description he has left us, even in those particulars which are so well calculated to cause surprise. The evidence of Ctesias, who saw Babylon some half century later, seems here and there to be tainted with exaggeration, but on the whole it agrees with that of Herodotus. Supposing that he does expand his figures a little, Ctesias is yet describing buildings whose ruins, at least, he saw with his own eyes, and sometimes his statements are borne out by those of Alexander’s historians.[72] The case of Nineveh is very different. Of that city Herodotus hardly knew more than the name; he contents himself with mere passing allusions to it.[73] Ctesias is trammelled by fewer scruples. When he wrote his history Nineveh had ceased to exist for more than two centuries; the statements of Xenophon[74] prove that at the time of the famous retreat its site was practically deserted and its name almost forgotten in the very district in which its ruins stood. But the undaunted Ctesias gives us a description of the Assyrian capital as circumstantial as if he had lived there in the days of Sennacherib or Assurbanipal. According to his account it formed an elongated rectangle, the long sides being 150 stades (17 miles 380 yards), and the shorter 90 stades (10 miles 595 yards), in length, so that the total circumference was 480 stades (55 miles 240 yards).[75] The whole of this space was inclosed by a wall 100 Greek feet (103 feet English) high, and with towers of twice that height. It is hardly necessary to show that all this is pure invention. To find room for such a Nineveh we should have to take all the space between the ruins opposite Mossoul and those of Nimroud. But all the Assyrian texts that refer to Nineveh and Calah speak of them as two distinct cities, each with an independent life and period of supremacy of its own, while between the two sites there are no traces of a great urban population. The 1,500 towers on the walls were the offspring of the same brain that imagined the tower of Ninus nine stades (5458 feet) high. We can scent an arbitrary assertion in the proportion of two to one given to the heights of the towers over that of the wall. In the fortified walls of the bas-reliefs the curtain is never greatly excelled in height by its flanking towers (see Vol. I. Figs. 51, 60, 76, and 158, and above, Fig. 23). [Illustration: FIG. 23.--Siege of a city; from Layard.]