After the decay of the Proto-Babylonian or Chaldæan empire (B.C. 2300–1500), when the seat of Interamnian rule moved to the Tigris-Euphrates basin, and the three Assyrian periods flourished (B.C. 1500–555),[358] iron was largely used. It was produced, according to Layard (_loc. cit._) in the Tiyari mountains, and it is still found in quantities on the slopes, three or four days’ journey from Mosul. The north-western palace of Nimrúd (Kalah) showed, amongst the rubbish-heaps, much rusty iron and a perfect helmet like that represented in the bas-reliefs. There were Swords and daggers, shields and shield-handles, rods, and the points of spears and arrows, which fell to pieces on exposure. Amongst the few specimens preserved were the head of a trident-like weapon, some Sword-handles, a large blunt spear-pile, the point of a pick, several objects resembling the heads of sledge-hammers, and a double-handed saw of iron or steel (?), about three feet eight inches long by four inches and five-eighths broad, for cross-cutting timber. The British Museum owns a fine collection of Assyrian sheet or plate iron-work; pieces of unfinished forgings; a rude triangular lump through which a round hole has been driven (by a heated punch?); several cylindrical bars, straight and curved; wall-cramps, nails, and door-hinges; a ladle; rings of sizes (one being three inches in diameter); a signet-ring containing a silver bezel or seal; and, lastly, a portion of what seems to have been a double-sided comb. In much later days the Assyrians of Xerxes’ army carried, according to Herodotus, shields, spears, daggers, and wooden clubs spiked with iron. The Greeks learned their metallurgy, as they did all their arts, from Egypt; and, following in the footsteps of the Phœnicians, diffused them throughout the Western World. In Theseus’ time, according to Wilkinson—that is, B.C. 1235—‘iron is conjectured not to have been known, as he was found buried with a brass (copper, bronze?) Sword and spear.’ They did not use iron weapons, and probably had no iron during their first foreign campaign—the Trojan war. The Parian (Arundelian) Chronicle (dating its notices from Cecrops, B.C. 1582) and the Rhodian myths refer to a conflagration in the Cretan mountains which taught metallurgy to the Idæan Daktyls (Δάκτυλοι Ἰδαῖοι):[359] this would, however, be a comparatively late date when we regard Egypt.[360]