After the conquest of Asia the Achæmenids generally gave to the fire-altars the form of Græco-Lycian chapels. In the sculptures of a royal tomb at Nakhsh-i-Rustam we see a king in adoration before Ormuzd, and a fire-altar, which has the form of a square block of masonry with projections in imitation of pilasters, supporting an entablature formed of three steps one above the other; the highest, larger than the other two, forms the platform on which the fire is lighted (fig. 141).[62] The architectural influence of Assyria is manifest in the construction of certain fire-altars. Near Firuzabad are the ruins of Jur, particularly interesting on account of the remains of an _atesh-gah_ ninety-one feet high, described by travellers, and apparently a copy of the staged towers (_zikkurat_) of Chaldæa and Assyria, a type of which, the most complete in existence, is here handed down to us. M. Dieulafoy remarks that the atesh-gah at Jur resembles the minaret of the mosque of Ibn Tûlûn, one of the oldest Mussulman edifices. Thus types of religious architecture invented by the Chaldæans exercised their influence even on the modern art of the East.[63] The funeral rites imposed by the Avesta had another consequence--that of creating a kind of architecture unknown in any country besides Persia. Human corpses might neither be committed directly to the ground, nor burnt, nor thrown into the river, for this would have caused pollution to water, earth, and fire. Cities of the dead had been established in remote and deserted spots: these were tall round towers called _dakhmas_, built of masonry, and showing no architectural ornament even round the top. These towers supported a wooden trellis-work on which the corpses were laid; birds of prey came and tore these abandoned bodies to pieces: they often carried off separate limbs to a distance, where wild beasts devoured what was left of them. That which remained in the charnel-house was buried, but previously covered with wax to avoid all direct contact with the ground. Herodotus has preserved a reminiscence of these distressing practices. “The corpse of a Persian” he says, “is not buried until it has been torn to pieces by dogs or birds of prey.... The Persians cover the dead body with wax, after which they inter it.” There is still at the present day in Persia a certain number of ruins of the sepulchral towers of the Mazdeans, and one of the best known is not far from Teheran. But the dakhmas only served for popular burials; for the Achæmenid kings, at any rate, broke the Mazdean law, which perhaps itself made in practice an exception in favour of the royal family. The tombs of the Achæmenid princes can be divided, from the architectural point of view, into two large classes, according as they are or are not anterior to the conquest of Egypt. The former are conceived according to the style and plan of Græco-Ionian tombs, the latter according to the Egyptian hypogæa.