The Bireme or two-banked oared vessel, which had been the principal warship in the Mediterranean for centuries, was superseded in the sixth century B.C. by the trireme. Thucydides, who is the first writer to provide us with any real information about them, says that the Corinthians were the first to have built triremes ‘in Greece’. This suggests that they may have originated elsewhere, for he goes on to say that ‘triremes in large numbers were first owned by the tyrants of Sicily and the men of Corcyra’. One thing that is certain - despite controversy which still exists as to the exact construction of the vessels - is that the trireme was rowed at three levels and there was one man to each oar. Evidence for this comes again from Thucydides who, in a passing remark, says: ‘It was decided that each sailor, taking his oar, cushion and oars trap–-’
In order to achieve the third bank of oars, what the designers had done was to provide the vessel with an outrigger: an extension beyond the ship’s side that gave the top level of oarsmen (‘thranites) a greater leverage. The total crew of a trireme consisted of about 200 men, of whom 170 were oarsmen. The thranites at the top numbered 31 on each side. Below them came the second bank (gygites) with 27 rowers to each side, and at the bottom, also with 27 men each side, came the thalamites. Both the two lower decks of oars were worked through holes or ports in the side, and it is clear enough that the least enviable position in the ship was that of the thalamites. They had little enough chance of escaping if the trireme was holed or otherwise overwhelmed. Aristophanes also makes the joking comment that it could be very unpleasant to be on the bottom tier if someone above decided to relieve himself. The remaining members of the crew consisted of fifteen deck hands, fourteen soldiers (some of whom were archers), and a flautist who piped the time for the oarsmen. The helmsmen, whose job was all-important on the ‘run-in’ towards an enemy trireme, steered by means of two broad-bladed steering-paddles as had been the fashion for centuries. In command of each trireme was atrierarch (master, and sometimes owner). Trierarchs were usually rich men of some consequence, and the competition between them to produce the finest and the most efficiently worked trireme was intense. True, they gained no financial reward for having the best ship and the best crew, except for a simple wreath or stephanos - as treasured then as medals in later centuries. Although the all-important oarsmen came from the poorer classes, they were free citizens -quite unlike the galley-slave labour of later years in the Mediterranean. It was the oarsmen, in fact, who by their predominance in numbers over the rich land-owning citizens were to provide the basic substratum upon which Athenian democracy was to evolve. Sometimes, as in modern days, they were no more than the tools of demagogues, but on rare occasions, as under men like Pericles, they formed the fertile sub-soil for the brief but golden age of Athens.
The Greek trireme, like the bireme before it, and like the singlebanked galley that survived in the Mediterranean as late as the eighteenth century, was almost entirely dependent upon manpower. Under favourable conditions with the wind from abaft the beam -preferably as far aft as possible - the trireme could be propelled by its simple squaresail which was set upon a short mast. Under fair-weather conditions, then, the trireme’s oarsmen could be given a respite, but in the fickle Mediterranean Sea it would rarely be for long. In any case, when it came to action, the trireme was entirely dependent upon manpower, for the cumbersome mast, sail and attendant rigging were stowed away or sent ashore before an engagement. This was why a fleet defending its home coastline would usually pick a place near a shelving beach where the unnecessary gear could be left behind. On the other hand, a fleet advancing, say, across the Aegean from the coastline of Ionia or elsewhere, might have come all the way under oars. The defensive fleet, therefore, even if outnumbered, always had an advantage over the attacker in the fact that its men would have spent less time at the oars before battle commenced.
From an inventory found in the dockyard of Piraeus it would seem that even the longest oars did not exceed four or four and a half metres in length. The ship itself, whose ancestry went all the way back to the hollowed canoe of primitive times, was long and narrow-gutted. On a beam of three metres at the bottom, which extended to six metres at the level of the thranites on the outriggers, the trireme would have been about 37 metres long. Such a vessel was clearly unsuited for heavy-weather work and, indeed, there were only about four, or at the most five, months of the year in which the trireme could safely operate. ‘The limitation factor in ancient warfare’, as I have said elsewhere, ‘was determined not only by the harvest season, when most of the nation’s population was engaged in ensuring the bread supply, but also by the fact that armies could not be transported, garrisons maintained, or sea battles fought, except in calm weather.’
The principal weapon of this period, as of the centuries before, was the vessel itself. It was the great underwater ram in the bows which was the forerunner of the cannon and guns of later days. The trireme was in fact launched at its opponent like a giant arrow. The moment of impact was ‘the moment of truth’ for all aboard. In order to withstand the shock, the vessel had to be specially constructed, and all-important - as of course in all ship construction -was the vessel’s keel. This was usually made of oak (with a false keel of some softer wood that could be replaced when it wore out through the constant hauling up, and launching from, a beach). The wooden ribs forming the supports on to which the vessel’s planking was set were firmly imbedded in the keel. The trireme’s planks, usually of pine, were laid one on top of another in what is called carvel fashion. They were fastened to the ribs by bronze nails or wooden dowels. The average thickness of a trireme’s planks would appear to have been about three inches.
The extreme length of the hull in proportion to the beam meant that additional longitudinal strength was necessary, and this was provided for by zosteres (‘waling-pieces’, in nautical terms), which were strong wooden planks extending from bow to stern designed to prevent the vessel from sagging in the middle. There were often as many as four of these zosteres to strengthen the weakness inevitably left by the oar-ports for the rowers. The lowest of them was the strongest and had a different purpose altogether. This waling-piece was cut and fashioned in such a way as to dip downward towards the bows, at which point it was firmly bolted from side to side through the great projecting beak of the ram. The ram itself was also made of wood but was sheathed with bronze. Since the whole ‘firepower’ of the galley consisted in ramming the enemy, it was essential that provision should be made for the ‘recoil5 or shock on the moment of impact. To reinforce the basic additional strength already provided by the zosteres, the hull was further strengthened by a series of heavy rope cables known as hypo^omata. These encircled the whole hull from stem to stern and gave even further longitudinal strengthening.
Some war vessels, and in particular those of Egypt, tended to carry a large number of heavily armed soldiers to board the enemy immediately after the ramming had taken place. This concept of, as it were, fighting a land-battle afloat was discarded after some time by most of the more experienced naval powers such as the Athenians and the Phoenicians. At the time of Xerxes, however, boarding parties were still all-important. The tactical use of the ram later became the paramount factor in any sea battle. Ideally, of course, the objective was to catch the enemy beam on, breaking clean into his ship’s side and holing him. But the ram could also be used by clever manoeuvring to run right down the side of the opponent snapping off the oars like matchsticks (the looms of the oars leaping back under the impact and killing or maiming the rowers). Having thus disabled the opponent, the trireme could then back off and, almost at leisure, come in and administer the coup de grace by holing the stricken enemy. It was, one might say, the far-distant, man-impelled, precursor of the torpedo.
Early representations of galleys from the sixth and seventh centuries show the ram as a long single spur projecting a considerable distance out from the bow. Such a single-headed long ram clearly had the disadvantage that it might well snap off in the enemy’s side, tearing open the bow of the attacker. At a later date it was found that a shorter but stronger ram, involving in some cases three separate points - rather like a trident - was more effective and could be better braced into the trident’s stem and sides. (This is shown on the prow of the famous Victory of Samothrace - about 300 B.C.) Further additions to the prow of the vessel were projections above the water-line on the stem itself, as well as heavy wooden catheads projecting on either side of the bows which protected the forward oars after the ram had penetrated, as well as serving to tear away the enemy’s upperworks as the trireme swept past in a sweeping blow.
During the years after Marathon, as the Persians girded themselves for the second round, the whole of the eastern and central Mediterranean saw a phenomenal increase in shipbuilding activity. It was not only in the Levant and Greece and the Aegean islands that the impending conflict made its presence felt. In Sicily the Greek colonies were only too well aware that the threat to Greece was a threat to themselves, and that the Carthaginians were enlarging their fleet not only to protect their colonies in Sicily but to evict and destroy the Greek colonies, most of which were planted on the eastern side of the island. Carthage, the offspring of Phoenicia, was determined to assert its claim to the control of the central and western Mediterranean. The whole of the ensuing conflict united such strange bed-fellows as the far-distant Ethiopians, and the mountain men of the Persian Empire, with the seamen of the Levant, Egypt and north Africa, as far afield as the great Gulf of Tunis where Carthage dominated the waters. In the face of such apparently overwhelming might it was hardly surprising that those Greek islands and mainland city-states which had not already medised were actively considering doing so. The only hope for Greece and for the future of its people and its culture lay in those two disparate states, Athens and Sparta. Now that Themistocles had largely committed the Athenians to being the naval shield of the country, it was clear that the brunt of an attack by land should be borne by the Spartans and other allies.