The most famous bituminous springs in Mesopotamia were those at Ḥit on the Euphrates. Their fame had reached Egypt as early as the time of the eighteenth dynasty, for Thothmes III brought bitumen thence to Egypt. Herodotus a millennium later—about 450 B.C.—alludes to Ḥit as famous for her bitumen, and subsequent writers make similar mention of the springs there. A good example of the early use of bitumen in Babylonia was found at Abû Shahrein, the site of ancient Eridu, where a very early building was excavated by Taylor, the antiquity of which was proved by the pre-Sargonic plano-convex bricks used in its construction, and these bricks were all laid in bitumen; the same was found to be the case in a building composed of finger-marked bricks at Ur (Muḳeyyer), all of which were embedded in bitumen.
The platform upon which Ur-Ninâ’s storehouse at Tellô was erected consisted of three layers of plano-convex and finger-marked bricks, all set in bitumen, while in the building underneath that of Ur-Ninâ, bitumen was also freely used.[52]
In like manner at Nippur, the finger-marked bricks of which the city-gate was constructed were laid in bitumen, though the bricks composing the early arch found on this site were set in mud, probably an indication that at the time when the arch was built bitumen was not used; around the base of Ur-Engur’s ziggurat on the other hand there was a coating of bitumen, while the crude brick altar found by Haynes in the lowest stratum at Nippur had a rim of bitumen; but in later times it was supplemented by the more tenacious lime-mortar, though only partially was this the case, for even as late as Nebuchadnezzar’s time (604-561 B.C.) its practical utility as a preventive against the destructive forces of rain were still recognized, the burnt brick retaining walls of his palace at Babylon being actually laid in bitumen. In like manner the bricks composing the old fortification wall, are rendered adhesive by means of a lavish prodigality of asphalt, so adhesive in fact, that it is often very difficult to separate them. Fortunately the side bearing the stamped inscription has its face downwards and therefore is not in immediate contact with the asphalt from which it is separated by the layer of reeds and clay already alluded to.
In the later buildings at Babylon, however, lime-mortar is also used, the transition period being marked by the employment of both in one and the same building, and in point of fact Koldewey found that in the case of one of the walls of a building of Nebuchadnezzar, one half of the wall was cemented together by means of asphalt, while in the other half lime-mortar alone was used. But in the new castle which Nebuchadnezzar built for himself on the Kasr, the very finest materials were employed, the bricks being of a pale yellow colour and extremely hard, contrasting with the bricks used in his earlier buildings, which are of a reddish-brown colour and less durable, while in this new structure, pure white lime-mortar alone is used. Lime-mortar, as well as mud-cement and bitumen, was employed at Nippur, as also at Birs-Nimrûd (Borsippa), and the mortar used has such adhesive properties that the bricks can only be separated by breaking them, while at Muḳeyyer (Ur) a mortar composed of a mixture of lime and ashes was employed.
In Assyria on the other hand, mortar seems to have been used more sparingly; when stone was employed as a building material, generally speaking no cement of any kind was used, the stones being carefully dressed so as to permit of no interstices, as for example was found to be the case with the stone retaining-wall round the ziggurat at Nimrûd; when ordinary crude bricks were employed, they were laid in a sufficient state of moisture to render them adhesive; while when burnt brick was the material in question, the mortar adopted was a mixture of clay and water. Bitumen however was by no means unknown in Assyria, but it was used chiefly under pavements or the limestone floors of sewers, to prevent leakage or infiltration.
STONE
The use of stone in Babylonia, as a building accessory, although seldom as a fundamental material, dates from the most ancient Sumerian times. A very early example of the use of stone for definitely architectural purposes in Babylonia is afforded by the pavement upon which a building at Lagash, found under the structure of Ur-Ninâ, was erected. The pavement[53] consists of slabs of limestone, three or four feet long, one and a half to two feet broad, and about six inches thick. The door-sockets, again, of some of the earliest rulers of Lagash have been brought to light, among which may be mentioned those of the illustrious Eannatum and Entemena, all being made of marble or some other hard stone, while in Eridu, one of the most ancient sites of civilization in the Euphrates Valley, stone seems to have been quite extensively used. The terraced artificial platform upon which the temple and city of Eridu were built was buttressed by a wall of sandstone, and the staircase which led up to the first stage of the ziggurat was made of polished marble slabs, which are now lying about casually on the mound; pieces of agate and alabaster were discovered, and granite was also employed there. Stone gate-sockets have been similarly found at Nippur and in the ruins of other early cities of Babylonia, while both the Semite Narâm-Sin, and the Sumerian Gudea a little later, brought heavy blocks of diorite from Magan, or Sinai, though apparently for sculptural rather than for architectural purposes.
In the Neo-Babylonian era stone was employed to a greater extent: the procession pavement of the god Marduk at Babylon, discovered recently by the Germans, was formed of slabs of limestone, bearing an inscription of Nebuchadnezzar, while Herodotus tells us that the bridge which then united the two banks of the Euphrates was made of “very large stones,”[54] and according to the classical writers, Strabo and Diodorus, the famous hanging gardens of Babylon, which Koldewey would locate to the east of the palace, were supported by stone architraves. But the stone used only for exceptional purposes in Babylonia, was re-used time and again, the ruins being regarded as a quarry, and consequently the stone has for the most part disappeared entirely.
In Assyria, on the other hand, stone was easily procurable and therefore readily used, though not to the extent one would expect, the reason being that the Assyrian was not an inventor but an imitator of his predecessor, the Babylonian, who afforded him little or no example in the working of stone. Accordingly even in Assyria, stone was for the most part used only for pavements, plinths and the lining of walls: at times however it was also used for the retaining walls which enclosed an artificial mound. The blocks of stone used for this latter purpose were sometimes of colossal size, measuring even as much as 6 × 6 × 9 feet and weighing some tons. The principal kinds of stone employed by the Assyrian architects were limestone, of varying degrees of hardness, and alabaster, which latter is often found in Assyria itself a little below the surface of the soil. Alabaster is a sulphate of chalk, it is grey in colour, soft, and admits of a high polish, but it is brittle and deteriorates in course of time. At Nimrûd (Calah) some of the drainage channels were covered with large slabs of limestone, and the ziggurat of Nimrûd, of which only one storey remains, was faced with a massive stone revetment wall, while occasionally stone columns appear to have been used, and one part of a column composed of carved limestone, some forty inches high and including both the capital and the upper part of the shaft in one piece has been actually discovered. Layard further found four bases of columns made of limestone, on the northern side of Sennacherib’s palace at Nineveh (cf. Fig. [14]). Sometimes the lintels of doors were made of stone; one such stone lintel was found by George Smith at the entrance to the hall in Sennacherib’s palace, while the sill or threshold generally, or at all events very frequently, consisted of alabaster or limestone. Similarly the floors of the more important rooms were formed of limestone-slabs.
The harder stones were notwithstanding sometimes employed in Assyria just as limestone was occasionally used in Babylonia, but as a general rule, in either case for sculptural rather than building purposes. The well-known black obelisk of Shalmaneser II (860-825 B.C.) already alluded to, was supposed to afford a good example of the use of volcanic stones in the northern country, but the material of which it is made is probably alabaster. A basalt statue of this same king was however brought to light by the German excavations at Ashur some few years ago, while the capital of a column found on the same site, belonging possibly to the time of Tiglath-Pileser I, gives us an illustration of the use of hard stones for purely architectural purposes by the Assyrians. It is uncertain from what quarter they obtained these harder stones, but basalt and other igneous rocks may be quarried in the valleys of the streams that poured their waters into the Tigris and Euphrates, and in the valley of the Khabour Layard informs us that he discovered many extinct volcanoes.