Tilley's and Morrison's Triremes - Evidence and Practicality

Article excerpt

The designer of the reconstructed Greek trireme, Olympias, first proposed by John Morrison and now built and tested at sea, takes issue with Alec Tilley's divergent ideas and proposals about these ships, together with their practicality. The author is a naval architect.

Alec Tilley has, since 1976 (Tilley 1976), been suggesting that the term trieres, or trireme, referred to several types of ancient Mediterranean warships, smaller and simpler than the one first proposed in principle by John Morrison (1941), now generally accepted as the most likely form of the trieres, and recently reconstructed in Greece as a complete ship tested at sea.

Tilley's ideas about triremes certainly follow the general principle that, when recreating artefacts of the past, the minimum solution should be favoured. But when dealing with ships, it is not merely a matter of simplicity of form but also of necessary material strength, stability and performance. The price of under-shooting the minimum in any of these aspects is failure, functional or catastrophic.

The difficulty with Tilley's suggested triremes is that he seems not to have given much consideration to the hulls necessary to accommodate his proposed oar-systems. When one calculates their likely stability, performance and strength, they appear to be inadequate either for survival or, on account of the remarkable attested performances of Greek triereis, in speed under oar. These are grave shortcomings, no matter how much he tries to support his views by his own interpretations of evidence. The well-tried and tested 'rules' and methods of naval architecture by which ships of all kinds have long been designed to make safe and effective vessels cannot be ignored. But this is what Tilley seems to have done, in, moreover, fast oared ships whose hulls have to be closely integrated with their oar-systems if they are to be successful.

Nevertheless, although his ideas may not be universally supported by students of this field, it is right that they should not be ignored. As no critical discussion of them seems to have been published after a lapse of nearly 20 years, this article has been written as an attempt to fill some of that gap, so far as it can be done without going too far into technical detail, essential though that detail is to any proper critique of his proposed triremes.

Linguistic considerations

In suggesting that triremes had three oarsmen to a 'room' (Tilley 1992), i.e. on one bench or thwart extending right across the ship, he starts from the northern European usage of the term 'double-banked' to mean, of boats, that two men sit on one thwart, each pulling his own oar, one over each side of the boat. In pursuing that usage back in time and into the Mediterranean, Tilley omits to mention the oared warships which were standard in that sea for about three centuries or more, the triremi. Those had three oarsmen on each side of the ship, each pulling one oar from the bench in each room (should this be called a half-room, to be consistent with Tilley?). As this alia sensile oar-system had six men in each of Tilley's 'rooms', according to him it was a six-banked system and triremi were not really triremes, though there can be few who would dispute that they were.

This simple, if somewhat over-rigorous, linguistic approach may have led Tilley to misunderstand Morrison's use of the term 'room' (Morrison & Williams 1968: 155). Morrison's wording indicates that he was thinking of that space on each side of the ship separately, following the meaning plainly appropriate in the case of galleys like triremi, when discussing the term triskalmos as meaning having three tholepins for working oars and concluding that a trieres has three tholepins in each room on each side of the ship. Unlike multi-oared ships' boats, such as the naval cutter which Tilley used to demonstrate his theories, galleys were longer vessels with many more oars and they were designed for independent operation; they have nearly always had a middle-line gangway to enable them to be manned from the stern and then worked at sea. …