Such, we may believe, was the trireme of the palmy days of Athens. Built for speed, it was necessarily light and handy, and easily turned, so that the formidable beak could be plunged into the enemy's side, the moment a chance was given. But it required sea room for its man[oe]uvres, and in a narrow strait or land-locked harbour, such as that of Syracuse, was no match for the solid balks of timber with which Corinthian and Syracusan shipwrights strengthened the bows of their vessels. Against these the pride of Athens was hurled in vain, only to find itself broken up and rendered unseaworthy by the crash of its own ram. With the defeat of Athens comes in the fashion of larger vessels with more banks of oars, quadriremes, quinqueremes, and so on up to sixteen banks, when the increase of the motive power had been more than overtaken by the increase in bulk and weight. The principles of construction in these larger vessels seem to have been the same as in the trireme. The space for each man was probably somewhat less, and the handles of the upper tiers of oars were weighted with lead, so as to give a balance at the thowl between the parts outboard and inboard. A question difficult to solve has often been raised respecting the pace at which these ancient galleys could be propelled. If five-man power could be taken as equivalent to one-horse power, then for the propulsion of the trireme there would have been available about thirty-five horse power, but that would hardly give a very high rate of speed. There is a passage in Xenophon[3] in which he speaks of a distance of about 150 nautical miles, from Byzantium to Heraclea, as possible for a trireme in a day, but a long day's work. Assuming eighteen hours' work out of the twenty-four, a speed of something over eight knots per hour would be required for this, which may perhaps seem excessive. Still we may believe that by a crew when fresh a pace not less than this could be achieved. [3] _Anab._ vi. 42.