CHAPTER II.
THE PRINCIPLES AND GENERAL CHARACTERISTICS OF ASSYRO-CHALDÆAN ARCHITECTURE.
Chaldæa was the cradle of the civilization, and consequently of the art, whose characteristics we have to define. Now the soil of Chaldæa to a great depth beneath the surface is a fine loose earth, similar to that of the Nile Delta. At a few points only on the plain, and that near the Persian Gulf, are there some rocky eminences, the remains of ancient islands which the gradual encroachment of the two great rivers has joined to the mainland of Asia. Their importance is so slight that we may fairly ignore their existence and assert generally that Chaldæa has no stone. Like all great rivers, the Tigris and Euphrates in the upper and middle parts of their courses carry down pieces of rock from their native mountains, but after they enter upon the alluvial ground near the boundary between Assyria and Chaldæa their streams become sluggish, and these heavy bodies sink to the bottom and become embedded in the soil; the water no longer carries on with it anything but the minute particles which with the passage of centuries form immense banks of clay. In the whole distance between Bagdad and the sea you may take a spade, and, turn up the soil wherever you please, you will not find a stone as big as a nut.
In this absence of a natural stone something had to be found to take its place, and the artificial material we call brick was invented. The human intellect refuses to give up the contest with nature before the first obstacles that seem to bar its progress; if it cannot brush them aside it turns their flank. The least accident is often enough to suggest the desired expedient. The origin of almost all the great discoveries that are studded over the history of civilization may be traced to some lucky chance. The first inhabitants of Chaldæa fashioned rude kitchens for the cooking of their simple food out of moist and plastic clay, the fires of reed and broken wood lighted on these simple hearths reddened and hardened the clay till it became like rock. Some bystander more observant than the rest noted the change and became the father of ceramics. We use the word in its widest, in its etymological sense. Ceramics is the art of fashioning clay and burning it in the fire so as to obtain constructive materials, domestic utensils, or objects of luxury and ornament.[127]
Even before the first brick or pottery kiln was erected it must have been recognized that in a climate like that of Chaldæa the soil when dried in the sun was well fitted for certain uses. Among the débris left by the earliest pioneers of civilization we find the remains of vases which seem to have been dried only in the sun. But porous and friable pottery like this could only be used for a few purposes, and it was finally renounced as soon as the art of firing the earth, first in the hot ashes of the domestic hearth, and afterwards in the searching flames of the close oven, was discovered. It was otherwise with brick. The desiccation produced by the almost vertical sun of Mesopotamia allowed it to be used with safety and advantage in certain parts of a building. In that condition it is called crude brick, to distinguish it from the harder material due to the direct heat of wood fires.
In any case the clay destined for use as a building material was subject to a first preparation that never varied. It was freed from such foreign bodies as might have found their way into it, and, as in Egypt, it was afterwards mixed with chopped or rather pulverized straw, a proceeding which was thought to give it greater body and resistance. It was then mixed with water in the proportions that experience dictated, and kneaded by foot in wide and shallow basins.[128] The brickmakers of Mossoul go through the same process to this day.
As soon as the clay was sufficiently kneaded, it was shaped in almost square moulds. In size these moulds surpassed even those of Egypt: their surfaces were from 15¼ to 15½ inches square, and their thickness was from 2 to 4 inches.[129] It would seem that these artificial blocks were given this extravagant size to make up for the absence of stone properly speaking; the only limit of size seems to have been that imposed by difficulties of manufacture and handling.
Crude brick never becomes hard enough to resist the action of water. In Greek history we read how Agesipolis, King of Sparta, when besieging Mantinea, directed the stream of the Ophis along the foot of its walls of unburnt brick, and so caused them to crumble away. Cimon, son of Miltiades, attacked the defences of Eion, on the Strymon, in the same fashion. When desiccation was carried far enough, such materials could be used, in interiors at least, so as to fulfil the same functions as stone or burnt brick. Vitruvius tells us that the magistrates who had charge of building operations at Utica would not allow brick to be used until it was five years old.[130] It would seem that neither in Chaldæa nor still less in Assyria was any such lengthy restriction imposed. It is only by exception that crude bricks of which the desiccation has been carried to the farthest possible point have been found in the palaces of Nineveh; almost the only instance we can give is afforded by the bricks composing the arches of the palace doorways at Khorsabad. They are rectangular, and into the wedge-shaped intervals between their faces a softer clay has been poured to fill up the joints.[131] As a rule things were done in a much less patient fashion. At the end of a few days, or perhaps weeks, as soon, in fact, as the bricks were dry and firm enough to be easily handled, they were carried on to the ground and laid while still soft.
This we know from the evidence of M. Place, who cut many exploring shafts through the massive Assyrian buildings, and could judge of the condition in which the bricks had been put in place by the appearance of his excavations. From top to bottom their sides showed a plain and uniform surface; not the slightest sign of joints was to be found. Some might think that the bricks, instead of being actually soft, were first dried in the sun and then, when they came to be used, that each was dipped in water so as to give it a momentary wetness before being laid in its place. M. Place repels any such hypothesis. He points out that, had the Assyrian bricklayers proceeded in that fashion, each joint would be distinguishable by a rather darker tint than the rest of the wall. There is nothing of the kind in fact. The only things that prove his excavations to have been made through brick and not through a mass of earth beaten solid with the rammer are, in the first place, that the substance cut is very homogeneous and much more dense than it would have been had it not been kneaded and pressed in the moulds; and, secondly, that the horizontal courses are here and there to be distinguished from each other by their differences of tint.[132]