There is a Greek word _askos_, which signifies a leathern bag or wine-skin, from which the word _askoma_ is derived. The latter was the word given to a leathern bag which was attached to the oar so as to prevent the water from penetrating through into the ship, and yet allowed, with only slight friction, the oar to be brought backward and forward. There is something slightly similar to-day in the leather flap which is found on the Bristol Channel pilot cutters, covering the discharge from the watertight cockpits, the motion of the ship through the water causing the flap to be pressed tightly against the hull, and thus preventing any water from entering. But in the instance of the Grecian craft the flap was much bigger. There were no rowlocks, but the oar was fastened by a leathern loop to a thole-pin against which the rower pulled his oar. Bear in mind that, whereas the Greek merchant-ship mostly relied on sails, the warship was essentially oar-propelled. And because she must needs carry a large number of rowers they needed supervision. Hence a gangway was placed on either side of the ship, both for that purpose and also for the placing of the fighting men. Illustrations on ancient Greek vases clearly show that some warships were fitted with a hurricane-deck above, and this extended down the length of the ship, but not from one side to the other. This hurricane-deck, if we are to give any credence to contemporary illustrations, was a fairly light affair raised on vertical supports of sufficient strength. In addition to the human ballast of the oarsmen, gravel, sand, and stone were used for trimming the ship. For instance, it might be necessary to get the bows deeper into the water so that the ram came into operation; or, after ramming and receiving damage, it might be found advisable to trim the ship by the stern so as to get the bows well out of water. To what extent these craft leaked one cannot say; but one can reasonably suppose that as they were built of unseasoned wood, as the shocks from ramming were very injurious, and as they had to suffer a good deal of wear and tear through frequent beaching, they made a fair amount of water. At any rate, it is certain that they provided against this in arranging an Archimedean screw, worked by a treadmill, or buckets for getting rid of the bilge-water. It is probable, also, that the drinking-water in cisterns or skins would be deposited as low in the hull as possible. The Greeks, in addition to their technical ability, had inherited a similar sea-instinct to that of the Phœnicians, and this keenness is by no means absent from Greek literature. What, for instance, could be more enthusiastic than the following exquisitely poetic extract from Antipater of Sidon:--