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WHEN WAS BITON?

BY

M.J.T. LEWIS

Biton’s treatise on the Construction of war engines and artillery has proved a headache to all who have studied it. Until the late Eric Marsden interpreted it along lines which are for the most part con- vincing, its mechanical detail remained almost impenetrable. Our present concern, however, is not with the technicalities of the trea- tise but with the other major problem, that of its date. To explain this problem it is necessary to sketch in the historical background1). Artillery was invented at Syracuse in 399 B.C. in the form of the gastraphetes, a mechanised version of the hand-bow, which followed the same basic lines as the later . Although at first a hand arm, it soon evolved into two larger and static versions, one shoot- ing heavy bolts and the other throwing stones. By about 370 it had reached Greece proper where, around 350 and probably in Mace- don under the aegis of Philip II, the fundamentally new principle of torsion was devised, whereby the bow was replaced by a pair of arms inserted into vertical springs formed of twisted skeins of hair or sinew and held in a frame. After the death of Alexander torsion arrow- shooters and stone-throwers were in widespread use throughout the Greek world in field warfare and especially in siege work, both in attack and defence. A programme of intensive research and devel- opment around 270 came up with refined proportions and complex formulae for calibration, which brought the torsion to a state of comparative perfection and high performance. Thereafter the Greeks added only relatively minor refinements. This is the briefest of summaries of a complicated story, and clos- er detail need not bother us. But the outline is right. The evolution of Greek artillery is well attested by specialist technical treatises and by a host of minor sources, whether literary, archaeological or epi- graphic; and, as a result of detailed study by a succession of schol- 1) The standard (and classic) work is E.W. Marsden, Greek and Roman Artillery: Historical Development (Oxford 1969) (= Marsden 1969) and Greek and Roman Artillery: Technical Treatises (Oxford 1971) (= Marsden 1971). © Koninklijke Brill NV, Leiden, 1999 Mnemosyne, Vol. LII, Fasc. 2 928 02-03-1999 16:48 Page 160

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ars, we know more about than about any other of the many machines devised by the Greeks. We can therefore state with confidence that in the second half of the fourth century the princi- ple of torsion came to rule the artillery roost. The older non-torsion catapult was quite rapidly squeezed out, and there is not a single ref- erence in any kind of source to such a machine being built between the end of the fourth century B.C. and the limited reappearance of the small hand-held arcuballista in imperial Roman times. Against this clear-cut background, Biton’s treatise has long stood out as an awk- ward embarrassment because, while it must have been compiled in the heyday of torsion, the artillery it describes is entirely non-torsion. Although addressed to a king Attalus, the treatise, terse and high- ly technical, is clearly written for the craftsman rather than the lay- man. It is, moreover, not an original work but a compilation of spec- ifications for six devices which date not from Biton’s own day but from earlier periods. (1) A small non-torsion stone-thrower built at Rhodes by Charon of Magnesia. (2) A non-torsion stone-thrower built at Thessalonica by Isidorus of Abydos. (3) A giant siege tower built for Alexander the Great by Posi- donius of Macedon. (4) A sambuca built by Damios of Colophon. (5) A medium non-torsion gastraphetes (arrow-shooter) built at by Zopyrus of Tarentum. (6) A non-torsion gastraphetes for field use built at by the same Zopyrus2). Of these builders only Posidonius, though otherwise unknown, is firmly dated by the reference to Alexander. Zopyrus has been plau- sibly equated with a Pythagorean of that name who flourished no later than the mid-fourth century3). Charon’s stonethrower at Rhodes is thought to pre-date the Macedonian occupation of 332 (Marsden 1969, 75). Damios and his sambuca will concern us short- ly. Isidorus’ engine must post-date the foundation of Thessalonica in 2) Full edition Marsden 1971, 64-77, with translation and notes. The only ear- lier study of any value is A. Rehm and E. Schramm, Bitons Bau von Belagerungsmaschi- nen und Geschützen, ABAW, NF 2 (1929), with translation. Later but partial studies are O. Lendle, Die Sambyke des Damios, in: J. Cobet, R. Leimbach, A.B. Neschke- Hentschke (ed.), Dialogus für Harald Patzer (Wiesbaden 1975) (= Lendle 1975), 111- 127, and O. Lendle, Texte und Untersuchungen zum technischen Bereich der antiken Polior- ketik, Palingenesia 19 (Wiesbaden 1983) (= Lendle 1983), 38-58, 107-113. 3) H. Diels, Antike Technik3 (Leipzig 1924), 23.