§ I Principles of Construction
The limestone which is furnished in abundance by the lowest spurs of the mountains of Kurdistan enabled the architects of Nineveh not to employ brick exclusively, and sometimes to erect walls of trimmed ashlar. They used limestone especially for the basements of the buildings, which were more particularly exposed to the action of damp, so fatal to crude brick; they also had recourse to it for the construction of the ramparts of the royal palaces. But even here, on account of the dearness of the materials, which it was necessary to seek at a distance and to spend much time in hewing, stone is only employed for the outer facing of the wall; the builders use it sparingly, and are as niggardly of it as they are prodigal of brick. Accordingly, the walls which enclose the terrace of Sargon’s palace at Khorsabad are only of stone on the surface; the interior, or rather the nucleus of the structure, is of brick. The blocks on their external and visible surface are of variable length, but are placed upon one another in very regular courses of equal height and with crossed joints. Headers penetrate like wedges into the mass of the terrace to ease the layers of brick and bind them to the stone structure. In the lower courses of the rampart of the palace at Khorsabad there are regularly hewn blocks from 8 ft. 2 in. to 9 ft. 10 in. square; the blocks diminish in volume in proportion to the nearness of the layers to the summit of the rampart, which was 59 ft. high, including the battlements, which formed a parapet all round the terrace.
The interior or exterior walls of the building which stood upon this gigantic base had no need to fear the infiltration of water or the attacks of enemies: their solidity might be lessened without inconvenience, by economising the stone. As a matter of fact, they are of brick, baked or crude, and stone is scarcely employed in them except for the lining and paving of a few rooms. In that case great slabs of limestone or gypsum are set upright as a plinth against the lower part of the wall, to preserve it from corrosion; they are adjusted end to end by the edge, and it was sufficient, in order to fix them, to pour between their posterior surface and the wall mortar which often only imperfectly adhered: the outer and only visible surface of these slabs was decorated with bas-reliefs which served for the adornment of the halls. As for the walls themselves, they were straight and perpendicular in contrast to those of the Egyptian buildings, which, seen from without, seem to lean inwards, and give to the whole building the appearance of a truncated pyramid. The Assyrian walls rise vertically, even when they enclose vaulted chambers, or when they form part of staged pyramids; each stage forms a perpendicular terrace, not a sloping one.
It has been observed that the partitions which separate the halls sometimes look like one block set up on end; the joints and the courses of the brickwork cannot be detected, to such an extent have the constructing materials been soldered together in a perfect amalgam of beaten clay. This peculiarity, noticed by Victor Place at Khorsabad, can only be explained by admitting that the bricks were employed in the building while they were still saturated with water, and before the process of drying was finished. Their natural dampness, added to that of the clayey mortar which bound them to one another, has formed a sort of muddy paste which must have taken years to harden, but which was particularly effective against the disintegration of the wall, since it became in this way entirely homogeneous. It was the extraordinary thickness of these walls which prevented them from giving way under their own weight, and even allowed them to uphold those heavy beds of clay which form the vaults and terraces of the houses. They thus protected the halls most effectively from the ardent heat of the sun. At the present day the inhabitants of Bagdad and Mosoul take refuge, during summer, in their sirdab, a half-underground room with extremely thick brick walls, the single opening of which looks to the north. The people of Nineveh and Babylon, subject to the same climatic conditions, certainly acted in the same manner. As for the princes, they had, to defend them against the sun, walls from 13 ft. to 26 ft. thick, and vaultings as enormous as the walls. Nevertheless, the mode of building with clay which we have just noticed was very defective; this is the weak side of Ninevite and Babylonian buildings, and we understand why the kings are unceasingly obliged, as they relate in their inscriptions, to repair or rebuild walls which crumble under the dissolving action of water from the sky.
The unusual thickness of the walls, the long, narrow form of all the chambers, are also justified by the employment of the vault as the essential element of the Assyrian buildings. V. Place unearthed at Khorsabad a great doorway surmounted by a semicircular arch. The sides of the doorway, as well as the arch itself, are of brick; there are three rows of voussoirs one above the other, forming as it were three concentric door-frames half-fitting into one another. All the voussoirs, which have issued from a single mould, have a slightly trapezoidal shape, like the stone voussoirs of our most carefully built edifices. The height of the doorway, under the keystone, is 19 ft. 8 in., and the breadth 11 ft. At other points, Place recognised that the enormous accumulation of materials which filled up the halls could only come from the falling in of the clay vaults. Some blocks still, at the time of the excavations, formed an arch, sometimes several yards in diameter, solid enough to serve as shelter for the shepherds of the neighbourhood; they were, on the concave side, covered with carefully laid stucco, or with paintings in fresco—a circumstance which proves positively that these blocks are sections of crumbled vaults.
The square chambers were surmounted by a dome; there are in the palace of Sargon two of these rooms as much as 44½ ft. square. In a bas-relief discovered at Kouyunjik (fig. 39) a group of houses figures, among which some are surmounted by hemispherical cupolas, others by elongated domes in the form of sugar-loaves. The houses of Babylon were vaulted, as Strabo tells us. The Mesopotamian palaces of the Achæmenid, Parthian, or Sassanian epoch, the halls of which are surmounted by domes which scarcely yield in boldness to those of St. Sophia, evidently only handed on the Assyro-Chaldæan tradition which is also represented before our eyes by the modern houses of Mosoul, Bagdad and southern Persia. The technical methods of contemporary masons also do not fail to make known to us what steps their ancestors of the time of Sargon or Nebuchadnezzar took to supply the want of wood, and in consequence to do without a previous arched framework: travellers tell us that they have observed the commonest workmen of the country erecting their hemispherical or elliptical cupolas by layers in rings, laid one above the other, and narrowing in proportion to their nearness to the keystone; it is the same principle as that of the corbelled vaulting.
The place where it has been possible to observe the employment of the vault in the architecture of the Assyrian palaces, is in the very bowels of the basements of these edifices. A vast corridor, surmounted by a semicircular vaulting, was discovered by the English explorers, in the flanks of the mound of Nimroud; the lower courses are of enormous slabs of stone, all the rest is brick. In the scientific system of drains which carried off the sewage of the palace of Sargon, Place distinguished every kind of vaulting: the pointed or ogival vault, the semicircular vault, the flat-arched vault, the shallow vault, the elliptical vault.
Never, at any point in their history, did the Egyptians or the Romans push the application of the vault to an equal degree of perfection. In most of the halls of Sargon’s palace a slab pierced with a hole was remarked in the middle of the bricks which form the pavement: this was the orifice of a vertical conduit opening into a vaulted drain concealed in the terrace. One of these drains had an ogival vaulting, the description of which we will borrow from MM. Perrot and Chipiez.29 “The bricks composing it are trapezoidal in shape, two of their sides being slightly rounded—the one concave, the other convex. The radius of this curve varies with each brick, being governed by its destined place in the vault. These bricks go therefore in pairs, and as there are four courses of bricks on each side of the vault, four separate and different moulds would be required, besides a fifth, of which we shall presently have to speak. The four narrow sides of these bricks differ sensibly from one another. The two curved faces, being at different distances from the centre, are of unequal lengths; while, as the lower oblique edge is some inches below the upper in the curve, these two edges have different directions. In their disinclination to use stone voussoirs the Assyrian builders here found themselves compelled to mould bricks of very complicated form, and the way in which they accomplished their task speaks volumes for their skill.” The two upper voussoirs meeting and touching one another by one of their corners, the triangular space left empty between their edges was filled up either by wedge-shaped bricks or by mortar. The drain which we have just given as an example is 4 ft. 7 in. high under the keystone and 3 ft. 8 in. broad; the explorers were able to follow it to a length of 216 feet. To facilitate its construction the architect conceived the ingenious idea of building it upon an inclined plane—that is to say, that all the rows of voussoirs, instead of being perpendicular, lean considerably backwards, and are supported one upon the other; this system, which did not at all affect the solidity of the vaulting, allowed the builders to do without circular wooden frames.
So much technical skill devoted to the construction of simple subterranean conduits makes us particularly regret that the deplorable quality of the material did not allow the vaults and domes of the palaces to exist till our day. However, there were not only vaulted halls in the Ninevite buildings; a certain number of them were covered by flat roofs formed of beams of palm-wood, poplar-wood or cedar-wood, which supported light terraces. The bas-relief at Kouyunjik which we cited above shows us flat roofs side by side with parabolic and spheroidal cupolas. Nevertheless, what we said about the use of stone in the Ninevite structures we can repeat here on the subject of timber. Nineveh, not being too remote from the wooded mountains of Armenia, Kurdistan and Masius, where forests of pines, beeches, and oaks grow, did not deprive herself of the use of these woods in her structures; she had panelled halls in her palaces, and, at the apogee of her power, when thousands and thousands of slaves placed their strength at the service of her monarchs, she had the timber of the Amanus and the Lebanon transported into her buildings. The king Assur-nasir-pal (B.C. 882-857) relates in one of his inscriptions that he had an enormous quantity of pines, cedars, and oaks cut down in the Amanus and the Lebanon in order to have them carried to Nineveh, and to employ them in the construction of his palace and the temples of his favourite gods. Other princes, such as Sargon, Sennacherib, Assurbanipal and Nebuchadnezzar, make the same boast of having utilised, in the buildings which they erected or repaired, beams brought from the Amanus and the Lebanon. “I caused the tallest cedars of Lebanon,” says Nebuchadnezzar, “to be brought to Babylon; the sanctuary of E-Kua, in which the god Marduk dwells, was freshly covered with beams of cedar-wood.”30 This is the wood of resinous nature, “the odour of which is good,” add the inscriptions. At the British Museum fragments of a cedar beam, collected among the ruins of Assur-nasir-pal’s palace at Nimroud, are preserved. Who will ever be able to say what efforts and how many human lives were required to transport these gigantic rafters across a rough country without any roads for traffic, from the Lebanon as far as the banks of the Tigris and Euphrates? Accordingly it may be affirmed that the use of wood was always exceptional in the Chaldæo-Assyrian structures; it was never introduced except as an exotic element, of which the monarchs boast on account of its rarity. The climate and the nature of the Mesopotamian soil were better suited by thick vaultings, which, then as at the present day, never ceased to be the rule there.
Quite as little as the Chaldæans, and for the same motives, did the Assyrians make a frequent and regular use of the column as an element of their architecture. Victor Place notices, like the explorers of Lower Chaldæa, several façades in the palace of Sargon adorned with pilasters and half-columns of brick, projecting beyond the plane of the walls, and having no object except to relieve the monotony of the structure. Perhaps, too, these half-columns, which are found in groups of seven, had, like the two famous pillars in the Temple of Solomon, a mystical and symbolical meaning, the number seven playing an essential part among the mythological conceptions of the Chaldæo-Assyrians. Elsewhere a few bases of columns and a few monolithic capitals have been found, which prove that the Assyrians used stone supports for monumental porches, as we ascertained in the palace of Tello. A fragment of a bas-relief preserved at the British Museum, and coming from the palace of Assurbanipal, shows us (fig. 43) the façade of a great building adorned with a projecting roof, supported by four pilasters and four columns. The base of these columns rests on the back of gigantic lions, which seem to advance to meet one another, two and two. On the back of the lion the architect has placed a coussinet, surmounted by a torus and by the stem of the column. In the ruins of the palace of Kouyunjik, four bases of columns were found still in place, and seeming to belong to a covered gallery; there were also two small winged bulls with human heads, crowned with the tiara, and supporting on their back a spheroidal base decorated with geometrical designs in relief. At Nimroud Sir A. H. Layard noticed also two crouching sphinxes bearing bases of columns (fig. 44); according to the same architectural principle the foot of the arches rested upon the gigantic bulls which flanked the chief entrances of the palaces.
The stem of the columns was probably of wood, painted or covered with a metallic envelope. Round the inner courtyards there were, as in the courts of oriental palaces in our own day, porticoes formed of cedar beams resting on bases analogous to those which we have just noticed. Strabo31 reminds us that in Babylon beams of palm-wood were used in the construction of houses: “They are careful,” he says, “to wrap round each palm-wood pillar with rush-cords, which are then covered with several coats of paint.” Things were not done quite in this way in the houses of the rich and in princely residences. A fragment of a cedar beam of the size of a man was discovered at Khorsabad. It was still overlaid with a plating of bronze decorated with designs in repoussé, which imitate the bark of a palm-trunk.
An enormous block of limestone, 39 ft. 3 in. high, brought to light at Khorsabad, comprises an entire capital and a part of the stem at the same time (fig. 45); it is almost the only Assyrian capital known. It affects the spheroidal form, and its convex part is decorated with a double line of curved festoons in relief; there was a similar ornament, no doubt, at the base. Several capitals from Warka are also preserved at the British Museum, but they were found among ruins of the Sassanian epoch. Nevertheless the resemblance which some of them bear to the architectural features of the bas-reliefs is so close that they are probably representatives of a style inherited from a former period. They are of that form, so well known in the sculptures, which has the character of the Ionic order, and was probably its original.
In imitation of their southern neighbours the Assyrians used the column especially in chapels of little importance, in which the supports had no vault or terrace to uphold. Bas-reliefs from Khorsabad and Kouyunjik represent sanctuaries the roof of which is supported by small columns with a base and a capital, which partake at once of the Ionic and of the Doric order of the Greeks (fig. 47). These little structures recall the Chaldæan shrine of the god Samas (fig. 29). An object which appears to be the base of a small column exists in the Nimroud Gallery of the British Museum. It is of sandstone, and, to judge from its size, it must have formed part of a small chapel or shrine, such as we see in the sculptures. The ornamental design upon it is partly similar to that of the large capital figured above, but presents some variations from it. There is a small hole into which the pillar was doubtless fastened by a peg or metal dowel.
The Assyrian palace, like Arab houses, developed itself entirely in area, and not in height; there was rarely a second story on the platform. Nevertheless such a second story exists sometimes; it is then open at the sides, and the roof is supported by small columns. These columns, of wood rather than of stone or brick, form a gallery over the façade, and they are adorned at their upper extremity with a double volute as a capital. Bas-reliefs show us houses thus surmounted by a colonnade, which supports a light, flat roof of wooden beams. At the present day, houses in Kurdistan are still built on the same lines, and show an identical arrangement in two stories; the lower without windows, the upper open at the sides.
In a word, the Assyrians, like the Chaldæans, not having at their disposal building-stone in great abundance, were obliged to construct their edifices almost exclusively of brick, the capabilities of which they tried to the utmost. The result of this was that they never had those halls of columns which are the triumph of Egyptian architecture. However thick one may suppose pillars of brick, or columns formed of bricks moulded in the shape of segments of a circle, to be, these supports will never offer the same guarantee of solidity as the stone column. Wherever a heavy burden, such as a vault or a terrace, had to be supported, great walls were raised of an extraordinary thickness, which it would have been imprudent to pierce with windows capable of diminishing its resistance. Air and light only penetrated into the apartments by the doors; often, too, an opening was contrived at the summit of the vault or dome, formed of a cylindrical pipe of burnt clay carried through the entire thickness of the structure.