According to the Greek writers, Phoenician vessels were mainly of two kinds, merchant ships and war-vessels.[99] The merchant ships were of a broad, round make, what our sailors would call “tubs,” resembling probably the Dutch fishing-boats of a century ago. They were impelled both by oars and sails, but depended mainly on the latter. Each of them had a single mast of moderate height, to which a single sail was attached;[910] this was what in modern times is called a “square sail,” a form which is only well suited for sailing with when the wind is directly astern. It was apparently attached to the yard, and had to be hoisted together with the yard, along which it could be closely reefed, or from which it could be loosely shaken out. It was managed, no doubt, by ropes attached to the two lower corners, which must have been held in the hands of sailors, as it would have been most dangerous to belay them. As long as the wind served, the merchant captain used his sail; when it died away, or became adverse, he dropped yard and sail on to his deck, and made use of his oars. Merchant ships had, commonly, small boats attached to them, which afforded a chance of safety if the ship foundered, and were useful when cargoes had to be landed on a shelving shore.[911] We have no means of knowing whether these boats were hoisted up on deck until they were wanted, or attached to the ships by ropes and towed after them; but the latter arrangement is the more probable. The war-galleys of the Phoenicians in the early times were probably of the class which the Greeks called triaconters or penteconters, and which are represented upon the coins. They were long open rowboats, in which the rowers sat, all of them, upon a level, the number of rowers on either side being generally either fifteen or twenty-five. Each galley was armed at its head with a sharp metal spike, or beak, which was its chief weapon of offence, vessels of this class seeking commonly to run down their enemy. After a time these vessels were superseded by biremes, which were decked, had masts and sails, and were impelled by rowers sitting at two different elevations, as already explained. Biremes were ere long superseded by triremes, or vessels with three banks of oars, which are said to have been invented at Corinth,[912] but which came into use among the Phoenicians before the end of the sixth century B.C.[913] In the third century B.C. the Carthaginians employed in war quadriremes, and even quinqueremes; but there is no evidence of the employment of either class of vessel by the Phoenicians of Phoenicia Proper.