4]), where the pressure, though considerable, would not have been very extraordinary.
It would seem, therefore, to be doubtful whether the Assyrians were really guided by any constructive principle in their preference of one form of the arch over the other.
In describing generally the construction of the palaces and other chief buildings of the Assyrians, it has been necessary occasionally to refer to their ornamentation; but the subject is far from exhausted, and will now claim, for a short space, our special attention.

Beyond a doubt the chief adornment, both of palaces and temples, consisted of the colossal bulls and lions guarding the great gateways, together with the sculptured slabs wherewith the walls, both internal and external, were ordinarily covered to the height of twelve or sometimes even of fifteen feet.

These slabs and carved figures will necessarily be considered in connection with Assyrian sculpture, of which they form the most important part.

It will, therefore, only be noted at present that the extent of wall covered with the slabs was, in the Khorsabad palace, at least 4000 feet, or nearly four-fifths of a mile, while in each of the Koyunjik palaces the sculptures extended to considerably more than that distance.
[Illustration: PLATE 60] The ornamentation of the walls above the slabs, both internally and externally, was by means of bricks painted on the exposed side and covered with an enamel.

The colors are for the most part somewhat pale, but occasionally they possess some brilliancy.