In order to grasp the character of the new evidence, and the methods by which it has been obtained at Babylon, it is advisable to bear in mind some of the general characteristics of Babylonian architecture and the manner in which the art of building was influenced by the natural conditions of the country. One important point to realize is that the builders of all periods were on the defensive, and not solely against human foes, for in that aspect they resembled other builders of antiquity. The foe they most dreaded was Hood. Security against flood conditioned the architect's ideal: he aimed solely at height and mass. When a king built a palace for himself or a temple for his god, he did not consciously aim at making it graceful or beautiful. What he always boasts of having done is that he has made it "like a mountain." He delighted to raise the level of his artificial mound or building-platform, and the modern excavator owes much to this continual filling in of the remains of earlier structures. The material at his disposal was also not without its influence in the production of buildings "like mountains," designed to escape the floods of the plain.
The alluvial origin of the Babylonian soil deprived the inhabitants of an important factor in the development of the builder's art: it produced for them no stone. But it supplied a very effective building-material in its place, a strongly adhesive clay. Throughout their whole history the Babylonian architects built in crude and in kiln-burnt brick. In the Neo-Babylonian period we find them making interesting technical experiments in this material, here a first attempt to roof in a wide area with vaulting, elsewhere counteracting the effects of settlement by a sort of expansion-joint. We shall see, too, that it was in this same medium that they attained to real beauty of design.
Brick continued to be the main building-material in Assyria too, for that country derived its culture from the lower Euphrates valley.[12] But in the north soft limestone quarries were accessible. So in Assyria they lined their mud-brick walls with slabs of limestone, carved in low relief and brightly coloured; and they set up huge stone colossi to flank their palace entrances. This use of stone, both as a wall-lining and in wall-foundations, constitutes the main difference between Babylonian and Assyrian architectural design. Incidentally it explains how the earlier excavators were so much more successful in Assyria than in Babylonia; for in both countries they drove their tunnels and trenches into most of the larger mounds. They could tunnel with perfect certainty when they had these stone linings of the walls to guide them. But to follow out the ground-plan of a building constructed only of unburnt brick, with mud or clay for mortar, necessitates a slower and more systematic process of examination. For unburnt brick becomes welded into a solid mass, scarcely to be distinguished from the surrounding soil, and the lines of a building in this material can only be recovered by complete excavation.
An idea of the labour this sometimes entails may be gained from the work which preceded the identification of E-sagila, the great temple of Marduk, the city-god of Babylon. The temple lies at a depth of no less than twenty-one metres below the upper level of the hill of débris; and portions of two of its massive mud-brick walls, together with the neighbouring pavements, were uncovered by bodily removing the great depth of soil truck by truck. But here even German patience and thoroughness have been beaten, and tunnelling was eventually adopted to establish the outer limits of the ground-plan, much of the interior of which still remains unexplored.[13]
The Babylon which has now been partially cleared, though in its central portion it reaches back to the First Dynasty and to the period of Hammurabi, is mainly that of the Neo-Babylonian empire, when Nebuchadnezzar II., and Nabonidus, the last native Babylonian king, raised their capital to a condition of magnificence it had not known before. This city survived, with but little change, during the domination of the Achæmenian kings of Persia, and from the time of Herodotus onward Babylon was made famous throughout the ancient world. At that time Ashur and Nineveh, the great capitals of Assyria, had ceased to exist; but Babylon was still in her glory, and descriptions of the city have come down to us in the works of classical writers. To fit this literary tradition to the actual remains of the city has furnished a number of fascinating problems. How, for example, are we to explain the puzzling discrepancy between the present position of the outer walls and the enormous estimate of the city's area given by Herodotus, or even that of Ctesias? For Herodotus himself appears to have visited Babylon; and Ctesias was the physician of Artaxerxes II. Mnemon, who has left a memorial of his presence in a marble building on the Ḳaṣr.
Herodotus reckons that the walls of Babylon extended for four hundred and eighty stades, the area they enclosed forming an exact square, a hundred and twenty stades in length each way.[14] In other words, he would have us picture a city more than fifty-three miles in circumference. The estimate of Ctesias is not so large, his side of sixty-five stades giving a circumference of rather over forty miles.[15] Such figures, it has been suggested, are not in themselves impossible, Koldewey, for example, comparing the Great Wall of China which extends for more than fifteen hundred miles, and is thus about twenty-nine times as long as Herodotus's estimate for the wall of Babylon.[16] But the latter was not simply a frontier-fortification. It was the enclosing wall of a city, and a more apposite comparison is that of the walls of Nanking, the largest city-site in China, and the work of an empire even greater than Babylon.[17] The latter measure less than twenty-four miles in circuit, and the comparison does not encourage an acceptance of Herodotus's figures on grounds of general probability. It is true that Oppert accepted them, but he only found this possible by stretching his plan of the city to include the whole area from Babil to Birs-Nimrûd,[18] and by seeing traces of the city and its walls in every sort of intervening mound of whatever period.
As a matter of fact part of the great wall, which surrounded the city from the Neo-Babylonian period onward, has survived to the present day, and may still be recognized in a low ridge of earth, or series of consecutive mounds,[19] which cross the plain for a considerable distance to the south-east of Babil. The traveller from Baghdad, after crossing the present Nîl Canal by a bridge,[20] passes through a gap in the north-eastern wall before he sees on his right the isolated mound of Bâbil with the extensive complex of the Ḳaṣr and its neighbour, Tell 'Amrân-ibn-'Ali, stretching away in front and to his left.[21] The whole length of the city-wall, along the north-east side, may still be traced by the position of these low earthen mounds, and they prove that the city on this side measured not quite two and three-quarter miles in extent. The eastern angle of the wall is also preserved, and the south-east wall may be followed for another mile and a quarter as it doubles back towards the Euphrates. These two walls, together with the Euphrates, enclose the only portion of the ancient city on which ruins of any importance still exist. But, according to Herodotus and other writers, the city was enclosed by two similar walls upon the western bank, in which case the site it occupied must have formed a rough quadrangle, divided diagonally by the river. No certain trace has yet been recovered of the western walls,[22] and all remains of buildings seem to have disappeared completely on that side of the river. But for the moment it may be assumed that the city did occupy approximately an equal amount of space upon the western bank; and, even so, its complete circuit would not have extended for more than about eleven miles, a figure very far short of any of those given by Herodotus, Ctesias and other writers.
