REMAINS OF ASSYRIAN CITIES.--Enormous grass-grown mounds, enclosed by crumbled ramparts, alone mark the sites of the great cities of the Assyrian kings. The character of the remains arises from the nature of the building material. City walls, palaces, and temples were constructed chiefly of sun-dried bricks, so that the generation that raised them had scarcely passed away before they began to sink down into heaps of rubbish. The rains of many centuries have beaten down and deeply furrowed these mounds, while the grass has crept over them and made green alike the palaces of the kings and the temples of the gods. [Footnote: Lying upon the left bank of the Upper Tigris are two enormous mounds surrounded by heavy earthen ramparts, about eight miles in circuit. This is the site of ancient Nineveh, the immense enclosing ridges being the ruined city walls. These ramparts are still, in their crumbled condition, about fifty feet high, and average about one hundred and fifty in width. The lower part of the wall was constructed of solid stone masonry; the upper portion of dried brick. This upper and frailer part, crumbling into earth, has completely buried the stone basement. The Turks of to-day quarry the stone from these old walls for their buildings.] PALACE-MOUNDS AND PALACES.--In order to give a certain dignity to the royal residence, to secure the fresh breezes, and to render them more easily defended, the Assyrians, as well as the Babylonians and the Persians, built their palaces upon lofty artificial terraces, or platforms. These eminences, which appear like natural, flat-topped hills, were constructed with an almost incredible expenditure of human labor. The great palace-mound at Nineveh, called by the natives Koyunjik, covers an area of one hundred acres, and is from seventy to ninety feet high. Out of the material composing it could be built four pyramids as large as that of Cheops. Upon this mound stood several of the most splendid palaces of the Ninevite kings. [Illustration: RESTORATION OF A COURT IN SARGON'S PALACE AT KHORSABAD. (After Fergusson.)] The group of buildings constituting the royal residence was often of enormous extent; the various courts, halls, corridors, and chambers of the Palace of Sennacherib, which surmounted the great platform at Nineveh, covered an area of over ten acres. The palaces were usually one-storied. The walls, constructed chiefly of dried brick, were immensely thick and heavy. The rooms and galleries were plastered with stucco, or panelled with precious woods, or lined with enamelled bricks. The main halls, however, and the great open courts were faced with slabs of alabaster, covered with sculptures and inscriptions, the illustrated narrative of the wars and labors of the monarch. There were two miles of such sculptured panelling at Koyunjik. At the portals of the palace, to guard the approach, were stationed the colossal human-headed bulls. [Illustration: SCULPTURES FROM A GATEWAY AT KHORSABAD.]