The benches on which the rowers sat ran from the vessel's side to timbers which, inclined at an angle of about 64 deg. towards the ship's stern, reached from the lower to the upper deck. These timbers were, according to Graser, called the diaphragmata. In the trireme each diaphragma supported three, in the quinquereme five, in the octireme eight, and in the famous tesseraconteres forty seats of rowers, who all belonged to the same 'complexus,' though each to a different bank. In effect, when once the principle of construction had been established in the trireme, the increase to larger rates was effected, so far as the motive power was concerned, by lengthening the diaphragmata upwards, while the increase in the length of the vessel gave a greater number of rowers to each bank. The upper tiers of oarsmen exceeded in number those below, as the contraction of the sides of the vessel left less available space towards the bows. Of the length of the oars in the trireme we have an indication in the fact that the length of supernumerary oars ([perinheo]) rowed from the gangway above the thranites, and therefore probably slightly exceeding the thranitic oars in length, is given in the Attic tables as 14 feet 3 inches. The thranites were probably about 14 feet. The zygite, in proportion to the measurement, must have been 10-1/2, the thalamite 7-1/2 feet long. Comparing modern oars with these, we find that the longest oars used in the British navy are 18 feet. The University race is rowed with oars 12 feet 9 inches. The proportion of the loom inboard was about one third, but the oars of the rowers amidship must have been somewhat longer inboard. The size of the loom inboard preserved the necessary equilibrium. The long oars of the larger rates were weighted inboard with lead. Thus the topmost oars of the tesseraconteres, of which the length was 53 feet, were exactly balanced at the rowlock.