In the Assyrian biremes the oars of the lower tier were worked through holes in the vessel’s sides. This arrangement would of course at once supply a fulcrum and keep the oars in their places. But it is not so easy to see how the oar of a common row-boat, or the uppermost tier of a bireme, obtained their purchase on the vessel, and were prevented from slipping along its side. Assyrian vessels had no rowlocks, and in general the oars are represented as simply rested without any support on the upper edge of the bulwark. But this can scarcely have been the real practice; and one or two representations, where a support is provided, may be fairly regarded as showing what the practice actually was. In the figure of a _kufa_, or round boat, already given, it will be seen that one oar is worked by means of a thong, like the [--] or [--] of the Greeks, which is attached to a ring in the bulwark. In another bas-relief, several of the oars of similar boats are represented as kept in place by means of two pegs fixed into the top of the bulwark and inclined at an angle to one another. [PLATE CXXXIII., Fig. 6.] Probably one or other of these two methods of steadying the oar was in reality adopted in every instance. With regard to Assyrian commerce, it must at the outset be remarked that direct notices in ancient writers of any real authority are scanty in the extreme. The prophet Nahum says indeed, in a broad and general way, of Nineveh, “Thou hast multiplied thy merchants above the stars of heaven;” and Ezekiel tells us, more particularly, that Assyrian merchants, along with others, traded with Tyre “in blue clothes, and broidered work, and in chests of rich apparel.” But, except these two, there seem to be no notices of Assyrian trade in any contemporary or quasi-contemporary author. Herodotus, writing nearly two hundred years after the empire had come to an end, mentions casually that “Assyrian wares” had in very ancient times been conveyed by the Phoenicians to Greece, and there sold to the inhabitants. He speaks also of a river traffic in his own day between Armenia and Babylon along the course of the Euphrates, a fact which indirectly throws light upon the habits of earlier ages. Diodorus, following Ctesias, declares that a number of cities were established from very ancient times on the banks of both the Tigris and the Euphrates, to serve as marts of trade to the merchants who imported into Assyria the commodities of Media and Paraetacene. Among the most important of these marts, as we learn from Strabo, were Tiphsach or Thapsacus on the Euphrates, and Opis upon the Tigris.