ANCIENT BOAT DEPICTED ON VASE.
The ‘bireme,’ or two-banked vessel, does not appear in Homer. But, as we have seen, it was probably in existence before Homer’s time. If of Egyptian parentage, it was adapted for use on the Mediterranean waters by the shipwrights of Sidon or Tyre. It is a curious reflection that this remarkable evolution of banked vessels should, so far as we can judge, have occupied about two thousand years; the curve, if we may use the expression, of development rising to the highest point in the useless Tesseraconteres of Ptolemy, and after Actium declining to the dromons and biremes of the Byzantine Emperor Leo, and finally subsiding into the monocrota or one-banked vessels, the galleys of mediæval times.
The problem which taxed the ingenuity of those early shipwrights was briefly this, how to get greater means of propulsion by increasing the number of oars, without such increase in the length of the ship as would, by increased weight, neutralise the advantage and still further diminish that facility in turning which was of the greatest moment to the ancient war-vessel. Galleys with fifty oars on either side had already been constructed,[2] and all the speed that a hundred pairs of hands could give had been obtained, when the invention of the bireme exhibited the means of nearly doubling the power without much increasing the weight to be moved, since but little additional height or breadth was required.
[2] Perhaps even with a hundred, if έκατόζυγος is to be taken literally.
The normal adjustment of the horizontal space between the oarsmen was then, as it is now, regulated by that canon of the ancient philosopher, ‘Man is the measure of all things.’ Twice the man’s cubit gives room for his legs when in a sitting posture. Hence the two-cubit standard (σχ̅ημα ’διπηχαϊκόν) which is referred to by Vitruvius as the basis of proportion in other constructions besides ships and boats. Given this as the interscalmium (space between the thowls) or distance between points at which the oars in the same tier were rowed, it is clear that the rowing space of a vessel’s side would be, for a penteconter, or twenty-five a side, seventy-five feet, and for a hecatonter, if there ever was such a thing, 150 feet. To this must be added the parts outside the oarage space (παρεξειρεσία), for the bows ten feet, and something more, say twelve feet, for the stern. So that a penteconter would be a long low galley of about ninety-seven feet in length. The new invention nearly doubled the number of oars without increasing the length of the oarage space.
It was found that by making apertures in the vessel’s sides at about three feet from the water and dividing the space between the (zyga) thwarts, room could be made for a second row of men with shorter oars, but still handy and able to add to the propulsion of the vessel. For these seats were found in the hold (thalamus), and hence while the upper tier of the bireme took their name from the zyga, benches or thwarts, and were called ‘Zygites,’ the men of the lower tier were called ‘Thalamites.’ These names were continued when the invention of the ‘thranos,’ or upper seat, had added a third or upper tier with longer oars to the system, and so introduced the trireme. If the number of the zygites in the penteconter was twenty-five a side, and the first bireme was a converted vessel of that class, the number of thalamites, owing to the contraction of the bow and the stern, would necessarily be two or three a side less. Thus we may consider a converted penteconter to have been capable of carrying a rowing crew of between 90 and 100 men. Similarly a triaconter would have been capable of adding nearly twenty pairs of arms to her propelling power. When, in consequence of the new invention, vessels were expressly built as triremes, we may imagine that for convenience’ sake the benches or zyga would be a little raised, so as to give more room for the raised seat of the thalamites that was fastened on to the floor of the vessel.
The narrowness of the vessels affected the disposition of the rowers in the Greek galleys in a peculiar way. It is evident from the testimony of the ancients that they adhered strictly to the principle of ‘one man to each oar.’ The arrangement seen in mediæval galleys was absolutely unknown to them, and would not have suited them. It belongs to a different epoch and a different order of things, when the invention of the ‘apostis’ had made the use of large sweeps rowed by two or three men possible, and a vessel with sets of three rowing upon the same horizontal plane might be called a trireme, though utterly unlike the ancient vessel of that name.
In the ancient vessel the tiers of oarsmen must have sat in nearly the same vertical plane, obliquely arranged, one behind and below the other. Thus in the bireme the zygite, as he sat on his bench, had behind him and below him his thalamite whose head was about 18 inches behind the zygite thwart and a little above it. Moreover, as his seat was now a little raised, the zygite required an appui for his feet, which was formed for him on the bench on which the thalamite next below and in front of him was sitting; on either side of him his feet found a resting-place. As the zygite fell back during the stroke and straightened his knees, there was plenty of room for the thalamite below to throw his weight also on to his oar. There seems to have been but little forward motion of the body. The arms were stretched out smartly for the recovery, as we learn from Charon’s instructions to Dionysus in the ‘Frogs’ of Aristophanes, and then a driving smiting stroke was given (cf. the words έλαύνειν, παίειν, άναρρίπτειν ̔άλα πηδῷ) and the brine tossed up by the blade.