Fig. 33.—Brick from Khorsabad; Louvre. 1223 inches square, and 445 inches thick.
Compared with the towns of the lower Euphrates, Babylon was not far from mountains whence, by means of canals and rivers, she might have easily obtained a limestone of good quality. Even in these days, when commerce and industry have fallen so low in those regions, the gypseous alabaster from the neighbourhood of Mossoul is transported in no unimportant quantities as far as Bagdad. It is used for lining baths and those serdabs to which the people retreat in summer.[140]
The remains of the great capital show no trace of dressed stone. And yet it was used during the second empire in some of the great public works undertaken by Nabopolassar and more especially by Nebuchadnezzar. Herodotus, who saw Babylon, declares this in the most formal manner in his description of the bridge which then united, for the first time, the two banks of the Euphrates. While the river was bordered by quays of burnt brick, the bridge, says the historian, "was built of very large stones, bound together with iron clamps embedded in lead."[141]
That, however, was but one exception, and it was necessitated by the very nature of the work to be carried out. No cement was to be had which could resist the action of water for an indefinite period and maintain the coherence of brickwork subjected to its unsleeping attacks. In order to obtain piers capable of withstanding the current during the great floods, it was better too to use blocks of considerable weight, which could be held together by metal tenons or clasps.
It was but at rare intervals that buildings had to be erected in which the habits of ages had to be thus abandoned. Why is it that such works have perished and left no sign? The question may be easily answered. When the ruins of Babylon began to be used as an open quarry, the stone buildings must have been the first to disappear. This material, precious by its rarity and in greater request than any other, was used again and again until no trace of its original destination or of the buildings in which it was found remained.
In Assyria long chains of hills traversed the plain and stretched here and there as far as the borders of the two rivers, besides which the last buttresses of the mountains of Kurdistan came very near the left bank of the Tigris. These hills all contained limestone. Two sorts were found: one fine, hard, close grained, and a little shelly, the other softer and more friable.
For the decoration of his monumental doorways and the lining of his richest apartments, the architect chose and committed to the sculptor those fine slabs of gypseous alabaster of which so many examples are to be seen in the Louvre and British Museum. In the plains gypsum serves as a base or foundation for the wide banks of clay that spread over the country, and are much less thick than in the south of Chaldæa. Alabaster is there to be met with in great quantities, often but little below the surface of the soil.[142] It is a sulphate of chalk, gray in colour, soft and yet susceptible of polish. But it has many defects; it breaks easily and deteriorates rapidly on exposure to the air. The Assyrians, however, did not fear to use it in great masses, as witness the bulls in the Louvre and British Museum. Before removal these carved man-headed animals weighed some thirty-five tons, and some of those remaining at Khorsabad and Kouyundjik are still larger.
In Assyria as in Chaldæa the dark and hard volcanic rocks have only been found in a few isolated fragments. They were used by the statuary and ornamentist rather than by the architect, and we cannot say for certain where they got them. We know, however, that basalt and other rocks of that kind were found in the upper valleys of the streams that flowed into the two great rivers.[143]
The Assyrian architect had therefore only to stretch out his hand to win stone of a sufficiently varied nature from the soil of his own country or the flanks of its mountains. It was, of course, mediocre in quality but it had powers of resistance that fitted it for use in certain positions. At the first glance it is difficult to understand why so little use was made of it. But in truth stone was for the Assyrian no more than an accessory and complementary material; the bodies of his structures were never composed of it; it was mainly confined to plinths, pavements, and the internal linings of walls.
In spite of its apparent singularity this determined exclusion is to be easily explained. The Assyrian invented nothing. His language and his writing, his religion and his science, came from Chaldæa, and so did his art. When the kings of Resen, of Calech, and Nineveh, took it into their heads to build palaces, they imported architects, painters, and sculptors, from the southern kingdom. Why, it may be asked, did those artists remain so faithful to the traditions in which they had grown up when they found themselves planted among such different surroundings? The answer is, that nothing is more tenacious of life than those professional habits that are transmitted from one generation to another by the practical teaching of more or less close corporations, besides which we must remember that the Chaldæan methods were excellently well fitted for the satisfaction of those impatient princes at whose orders the works were undertaken. For the quarrying, dressing, and fixing of stone, a special and rather tedious education was required. The manufacture and laying of bricks was comparatively easy. A few weeks were sufficient to learn all that was to be learnt about the kneading and moulding of the earth, its desiccation in the sun or burning in the kiln. Provided that experienced men were forthcoming to superintend the latter operation, millions of good bricks could be made in the year.[144] All this required no lengthy apprenticeship. Their arrangement in horizontal courses or grouping at stated intervals, into those lines of battlements with which every wall was crowned, was done by the men of the corvée. Certain parts of the building, such as arches and vaults, required more care and skill, and were left, no doubt, to experienced masons and bricklayers, but, with these exceptions, the whole work could be confided to the first-comers, to those armies of captives whom we see in the bas-reliefs labouring in chained gangs like convicts.