Research Proposal : Digital Simulation of Galley Warfare

Take a look at Dr.Jorit Wintjes proposal for a research project that would examine the realities of ancient galley warfare. How would the naval tactics really have functioned?

 A  slideshow  lays out his ideas and can while away a few minutes.

Proposed in 2016,  wonder if it progressed any further ?

Take a look HERE

 Wintjes has a prolific output in connection with ancient naval themes. Some interesting titles below... Hopefully the digital galley battle simulator is coming soon?

• The ghost fleet of Seleucia Pieria, in: N. Hodgson, P. Bidwell, J. Schachtmann (ed.), Roman Frontier Studies 2009. Proceedings of the XXI International Congress of Roman Frontier Studies (Limes Congress) held at Newcastle upon Tyne in August 2009, Oxford 2017, 699-702.
• Sea power without a navy? Roman naval forces in the principate, in: M. Jones (ed.), New Interpretations in Naval History. Selected Papers from the Seventeenth McMullen Naval History Symposium, Newport (Rhode Island) 2016, 13-24.
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• The classis Britannica - Just a "normal" provincial fleet? in: A. Morillo (ed.), Proceedings of the 20th International Congress of Roman Frontier Studies (2006). Leon 2009, 47-56.
• Defending the Realm: Roman Naval Capabilities in Waters Beyond the Mediterranean, in: M. M. Yu (ed.), New Interpretations in Naval History. Annapolis 2009, 1-13.
•  The Classis Britannica - aspects of the history of Roman naval units in North Western Europe, in: Hadrianic Society Bulletin 2, 2007, 13-19.
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• On a plank and a prayer – The Roman “navies” of the 5th to 7th centuries – The Roman Army School 2014, Hadrianic Society, St Chad's College, Durham, April 2014.
• Fleeting Shadows on Shifting Sands? Roman Naval Bases in NW-Europe – The Roman Army School 2014, Hadrianic Society, St Chad's College, Durham, April 2014.
• Challenging the orthodoxy – the late Roman navy – The Roman Army School 2013, Hadrianic Society, St Chad's College, Durham, März 2013.
• Navy ranking, or: The tale of the troublesome trierarchs – The Roman Army School 2013, Hadrianic Society, St Chad's College, Durham, März 2013.
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• The Trireme – the ship that changed the ancient world? – International Commision of the History of Technology Conference, Barcelona Juli 2012.
• East of Suez – Roman Sea Power in the Eastern Mediterranean – Israeli Society for the Promotion of Classical Studies Symposium, Jerusalem Juni 2012.
• The “real” navy? The classis Ravennata – a case study  – The Roman Army School 2012, Hadrianic Society, St Aidan's College, Durham, April 2012.
• Sea power without a navy? Roman naval forces in the principate - 2011 Naval History Symposium, United States Naval Academy, Annapolis, September 2011.
• The battle of Bedriacum reconsidered - 2011 Spring Conference, British Commission for Military History, Lady Margaret Hall College, Oxford, Mai 2011.
• New research on the Roman navy - The Roman Army School 2011, Hadrianic Society, St Aidan's College, Durham, April 2011.

SHOCK AND OAR : Part III

 

One of the failings of much writing about galley warfare, and especially trieres combat, in the past has been to focus on the act of ramming only from the point of view of the target.


I have scribbled about rams and the effects on the target. What I would also like to get across is the fact that a ramming attack is a double-edged event. To put into perspective, to the other lunatics like me and maybe some half -interested others, how the full picture of what was going on in this type of combat was more complex, more uncertain. more frightening and more skillfull than is generally appreciated.

Dare you take to sea for battle in a trieres ?

Trieres combat, and galley combat in general, required the cooperative efforts of 200 or more  men to put to use the near-perfected product of thousands of hours of skilled work by experienced craftsmen. The whole project could be wrecked by poor management, a moment's error of judgement or the vagaries of nature. In the Second World War many thousands of tank crew took imperfect vehicles into combat and found the harsh realities of cooperation under restricted conditions while under threat of death an almost intolerable physical and psychological challenge.  A few moments could bring a shift between the vehicle and its crew being victorious and elated at destroying and damaging other vehicles and into a state of abject fear and trepidation as the enemy turned the tables on them. A lot of technology and training could be put in danger by a ditch beside the road, a poor electrical connection or if the team in the other tin can had a smidgin more luck or skill.

In the back of each crewman's mind....

Newton's Third Law was first defined and written down by him but many people had prior awareness of it. The crew of a trieres in particular. If a ram is accelerated into a target then the attacking ship will also feel some repercussions. Newton's First Law was felt by the oarsmen in their legs and arms as they accelerated the ship towards the target. Newton's Second law was appreciated by the kybernetes in his calculation of how much speed he could coax from his crew and how fast they could accelerate and how much momentum he would need to damage his target.

The Third Law means that the momentum of the attacker will come back to bite him if he slams his trieres into a target without regard to this relationship. It is one thing to shoot a stone ball into the wall of a town with as much force as one can generate from a katapeltes and quite another to treat a mass of wood populated by 200 men in the same way.

A trieres hitting an imoveable target will almost instantly decelerate to a stop.  The trieres is subjected to an opposite force which stops it dead. The crew also experience this opposite force, which also stops them dead- maybe literally. This is the same deceleration which affects the unfortunates in a car crash. This is what trieres combat with rams is about. A series of car crashes.: but car crashes which are executed deliberately and in a controlled manner.

The trieres in a car crash has two problems to overcome.

The first is that the structure of the ship should survive the impact. If it does not then the crew is lost anyway and even if the target is eliminated then they have gained no advantage for their side.

The second is that the crew should survive the impact. The crew must be able to continue the fight after damaging a target ship otherwise their effort gains no advantage for their side.

THE SHIP

A trieres had two systems which contributed to its survival in a collision.

The ram itself was mounted at the front of the vessel as an extension of the keel and supported by the stem post. The centre of mass of the ship is projected forward very closely to the driving centre of the ram which means their is little turning moment to stress the structure. The ram mounting is solid and braced to resist being deviated from a forward course as it impacts the target. The ram itself is of massive bronze and formed like a modern girder. It is harder and stonger than any wood it impacts. The whole structure of the ship is mounted onto the keel and this forms the axis of attack as it bears the whole mass of the ship into the target. Because the ship is built to withstand the force of the sea resisting its progress then it is well suited to surviving an impact along that same axis. It is not coincidence that the ram as a weapon developed out of the cutwater as a hydrodynamic structure. Trieres must have been built to withstand the expected stresses of combat impacts.

 In addition, the ship's crew were not passive passengers but riders who could act to help achieve an effective impact. The rowers could obey commands to accelerate or decelerate and the kybernetes could steer the ship into the target at an angle of attack of his choosing. A good kybernetes could judge, given an appreciation of the relative courses of his own ship and the target, the correct angle of impact to achieve a hole in the enemy's vessel.

THE CREW
The crew were well aware of the implications of the meeting, no matter how controlled, Flying oar looms and tight spaces under the deck left little scope for avoiding at least a sore head from an unexpected collision.

Brace,brace,brace : one possible method after Wegener-Sleeswyk

 The deck officers must have communicated the moment of expected impact to the keleustes and on to the oarsmen. The oars must be out of the water at the moment of impact and the men braced on the beams and benches around them to take the strain.  The stresses he would experience are about 1.5G which amounts to a man of 75kg being slammed in the front by 113kg or so. It gets worse. If the target is more massive than the rammer then deceleration is more sudden and the impact rises to a maximum of 2G. This means each rower must brace himself as if being slammed by 150kg or approximately 3 medium sized lambs or two unarmoured dwarves.

Multiplied by 2 !

 EXECUTING THE ATTACK : DON'TS

If the ram was slammed into the enemy ship at a wildly oblique angle then the lateral forces experienced by the ram mounting could shatter the structure and tear it off. This we know happened on a large scale in early ramming battles. Experience was gained and applied in future tactics.

If the approach to ram was conducted at too-acute an angle then it may either not bite, experiencing a greater resistance from the hull than if it was attacked obliquely, or the speed of a target pursued may be so great that the net ramming speed is insufficent to damage the target.

The combined impact velocity of the attacker and target must be kept in a range sufficient to breach the target's hull but insufficient to damage the attacker. This is why the best way to attack another ship was from the stern quarter.

Gets it right the second time ! A perfect anastrophe.

The worst way to attack another ship was on the bow quarter. In this configuration each vessel will experience a force equal to the sum of their momenta. A trieres built to sail at 15 knots and be rowed at 10 will be severely tried, to say the least, by a head-on impact at equivalent to 20 knots.

It was only marginally less bad to attack a target from the beam if the target was moving. If the target is crossing then the lateral stress on the bow timbers was at its maximum and this was the weakest aspect of its structure. In addition, the forces affecting the crew of the attacker would be severe. They would be thrown forwards by the deceleration of the impact AND to the side opposite to that to which the target was moving. Heaven help any on deck who did not have a good hand-hold in that situation.

And what of the human sardines squished amongst sweat, farts, bilge and curses into this high-speed wooden can and expected to hurtle themselves at an unseen foe? What happens to them on impact ?

So much seems to hinge upon the kybernetes that we can only increase our admiration for these men. They were not of sufficient social status to warrant more than a few cursory lines from ancient authors but it was their skill and judgement derived from years of experience which was the key to a successful ramming attack.

The kybernetes must control the speed of his vessel. He must control the angle of attack and he must judge the timing to perfection with his ship moving in three planes on the sea.

The poet Lucian wrote about the pilot of a giant grain freighter, The Isis, he visited in Athens harbour in AD. This was about a sailing ship of great size but a sneaking admiration is to be detected in this terse and outwardly disrespectful description of an unassuming kybernetes who must have nevertheless exuded a sense of great  skill and confidence.

'Samippus: And all depends for its safety on one little old atomy of a man, who controls that great rudder with a mere broomstick of a tiller! He was pointed out to me; Heron was his name, I think; a woolly-pated fellow, half-bald. 
Timolaus:  He is a wonderful hand at it, so the crew say; a very Proteus in sea-cunning.'
(Lucian - The Ship. 35)



EXECUTING THE ATTACK : DOS

Once the ram became de rigeur for sea battles, mariners must have rapidly gained knowledge of how to use it to best effect by reports spread of various trials and errors. Herodotos tells us that the Phoceans learnt an early lesson in his account of the battle of Alalia in 535bc. They won, but many of their ships were almost as wrecked as their targets, the bows being ruined by the impact forces.
By the time we have good evidence for the structure of warships we can see all the longitudinal timbers meet behind the ram so that all impact forces are distributed along the whole ship and focussed through the bronze tip of the ship.

To hit an enemy effectively only required a small advantage in speed to give the required excess force to penetrate the tenon-and-peg hulls of triereis. Computer simulation has established that  different types of wood in the target or different angles of approach do not significantly change the basic rule which is that an advantage of 1/2 knot in speed will mean a penetrating hit.

On the other hand this means that vastly excessive speed will send the attacker barrelling in to the target and as the breach widens and the attacker slows he is more likely to get wedged-in and unable to withdraw. In this classic situation the crew of the ruined ship will launch a frantic boarding attempt, seeking for survival aboard the (more) bouyant victor.

The same excessive speed will tumble deck passengers into the briney and injure some rowers.

Shock and Oars !

This means that lightness of touch was a required attribute of a successful warship commander. The cooperation between the deck officers to feed information to the poop deck and the cooperation - almost empathy - required between the kybernetes, pentekontarchos and trierarch could only be developed by intensive practice. Just when sufficient speed had been achieved, just where the best angle of attack lay to ensure a hit and space to back-off, and the exact moment at which to stop rowing and brace for impact should all be judged and broadcast to ensure an attack was delivered.

The best position for an attack was to sit on the tail of the target as per an aerial dogfight.
In this position the target's speed is obvious, any change of course he makes is signalled by movements of his pedalia. By the same token, the target cannot read the attacker's changes in course and speed until after a disadvantageous delay.

 

The other significant advantage of the tailing position is that when the ram is set at the target it will hit a receeding target at an acute angle which minimises the stresses on the attacker. Transverse stress were the worst in terms of damaging a ship's bows and converging course would give increased shock of impact.

In trieres combat the secret was to ram the enemy in the right place, from the right position of attack, and with just enough force necessary to do the job.

In later times, as larger ships appeared, one could count  more on the mass of ones' own vessel to survive impact especially against smaller vessels. The trieres was a Formula One vehicle rather than a Stock Car and had to be treated as such.

SHOCK AND OAR : PART II

The ram is an instrument used to project the kinetic energy of the attacker into the hull of the target. If the energy put into the structure of the target exceeds the stress limits for that structure then it is damaged. At sea a damaged structure fills with water to the disadvantage of its crew.

Sometimes, one must improvise.

Studies of ram function have accelerated since the discovery of the Egadi rams. Previously there were only three known and only 1 in perfect condition. Now we have many rams including some which show battle damage which can be analysed.

Bent blades - from Egadi

What is surprising is the similarity of form the rams show. They are similar across time from monuments in ancient Greece of 4^th century BC down to Rome of the first centuries AD. The found rams also show great similarity between Roman, Carthaginian and Greek examples.

Rams from Athens 4thcenBC?, on Arc de Triomph d'Orange 20BC, Egadi3(Carthaginian)241BC

We know the ancients were no slouches in the technological sense. If something could be made to function better then it would be adopted if the economic situation allowed. Witness the use of mechanical pumps, piped water, katapelta and the experimentation that produced Hero's steam turbine, Archimedes steam cannon etc. The Antikythera mechanism has been shown to be a wonderfully complex 'laptop' for celestial time and place calculations. It cannot have existed in isolation.

Not made by numbskulls

 The structural similarities the rams are showing us reveal effective mechanical principles that had been developed from experience and were held-to because they worked.

The earliest images we have of rams show – if they are true military rams and not cut-waters – rounded spike-like forms. 

Phoenician Ship ? From Nineveh

These would do the job of holing an opponent but the big problem with ramming as a tactic is at once apparent. Once one has smashed the ram into the opponent there is the problem of extrication. If the ram has a uniformly increasing size then the point exerts massive stress and will penetrate easily. As the point moves into the target the hole is widened as the rest of the ram follows.

At some point, however, the compressive and resistive forces counter the attacker's momentum and the intrusion is stopped and the ram is gripped. This is nicely illustrated by those of us who have energetically tried to split logs which are too wet or tough and, even though one strikes along the grain, they allow the blade of an axe in but grip it tight at some point allowing no escape.

Stuck in a slightly different way...

Boar spears and bayonets also have this problem – hence the cross-piece use to prevent deep penetration and the standard advice for bayoneteers to twist their weapon before attempting to pull it out of their adversary. 

 

The hull structure of ancient ships comprised planks laid edge-to-edge that were joined with many mortise-and-tenon joints. These were very tightly made. The resulting shell is very resistant to splitting and to lateral disruption. This kind of structure would grip a flat blade or a spike-formed penetration. A sheet of steel will simply fail and be punched open but a composite wooden structure will react elastically and grip the intrusion.

 

The solution to the problem of holing and disrupting a wooden hull of the type used in triereis is rather more cunning. One must break the planks to make gaps and one must also overcome some of the joints to make recovery impossible and one must prise the hole wider to allow a serious amount of water in.

Not surprisingly the ancient rams fit this purpose perfectly.

The form is at first somewhat disguised by the ancient aesthetics of seeing the only appropriate device for penetrating an enemy at sea as a trident. This is the weapon of Poseidon or Neptune, the lords of the undersea. If one's maritime enemy should be smitten it is only fair to call upon and to acknowledge the help of the earthshaker. So when we look at an ancient ram we see a trident from the side superimposed on the geometry of a technical solution to staving-in the hull of a ship. 

One of Poseidon's tridents on the sea floor at Egadi

It is not accidental that the ram has the three 'blades'. A single blade can wedge and be stuck. Two blades may penetrate but hold a single plank. Three blades can strike across two planks and three joint-lines giving a better chance of success. More blade are superfluous and begin to dissipate the force applied.

The blades hit the target like chisels or axe-blades with their blades entering along the grain. The widening profile splits the wood. The vertical extent of the ram means at least one joint line will be hit and, hopefully, burst. The strakes on ancient triereis wer in the order of 20 to 30 centimetres wide. The separation of the ram blades is of the same order thus ensuring a spread of attack across at least one and probably two joint lines and three or four strakes.

Side of hull impacted by ram (Oldfield2012)

 Once the blades have wedged open the target's planking then the momentum of the attacker is transmitted across the whole of the ram's cross-section – the so-called 'driving centre' – because the blades have a vertical cross-piece which joins them and presses all the wood in front into the target. This breaks the tenons out from their mortises. Once out of place they will never go back. There is no need to drive the ram deep into the target hull. It must just break the hull shell's integrity. (Steffy(1983) refers to this when he says the ram 'pounded' rather than pierced the target).

The hull shell of the target ships has now suffered a devastating blow from piston with sharp blades. The force developed by a triereis of circa 50 tonnes hitting at 10 knots has been calculated by John Coates as circa 66 tonnes. This is applied over the driving centre of the ram which is less than 50cm square. Something will give !

Hole made in hull. Police are looking into it.

Computer simulations (Oldfield 2012) have been run to discover how much energy is needed to breach hulls in relation to woods used and the relative velocities and inertia of triereis. The results confirm that the concept of ancient warships as massive hulks engaging each other like mastodons with rams instead of tusks and delivering terrible damage to each other until one succumbs are completely wrong.

 

The first point to be aware of that it is not speed we are discussing here but relative velocity. It makes a big difference to the impact if two ships are moving in the same or opposite directions. This will also have big implications for how we imagine triereis to operate, as we shall see. If the ships move towards each other the impact forces are much greater than if one is stationary or the target is moving away. 

Luckily, this is not a head-on collision so the force of impact will be reduced. Somewhat.

Oldfield discovered that the forces generated by a trieres ram are more than sufficient to catastrophically damage a trieres hull so long as the collision velocity was 0.5 knots ! No need for cries of 'ramming speed' and extra lashes for the galley slaves ! A smooth approach at reasonable speed would result in a nice smooth impact and busting of the target's flush. The best angles for attack were, as may be expected, those closer to perpendicular. The strength of the mortise-and-tenon hull is greater against acute-angled attacks. Also, attacks with high closing velocities had a much greater chance of success than those pursuing – but this has a downside we shall discuss later.

Successful attacks can be made in the arcs shown -for set relative velocities and wood(Oldfield2012)

These finding mean that the kybernetes would know he could count on holing the target in a head-on attack and in an attack against a fleeing enemy he had to strike a careful balance to deliver his maximum effect which, if done correctly only need a 0.5 knot advantage in speed to hole the target.

What we stand with now is a model for trieres battles which involves combatants more like first world war stringbags than mastodons.

Gertcha...!

The opponents can easily damage each other if they are given the chance but each also has a high degree of manoeuvrability to use in evading being hit – or making a hit. Once hit effectively the game was probably quickly up (see this blog entry -  'Get Down Ship' 20/08/14).

The weapon developed to equip the trieres was well suited to its purpose. It is hard to imagine a better form. It was developed with full knowledge of the hull construction techniques then in use and exploited their weaknesses. These weaknesses would be well-known to the commanders – kybernetes, pentekontarchos and trierarch, as they stood anxiously on the poop-deck and sought to manoeuvre their ship to ensure its survival and success.

"And all depends for its safety on one little old atomy of a man, who controls that great rudder with a mere broomstick of a tiller! He was pointed out to me; Heron was his name, I think; a woolly-pated fellow, half-bald."                             -Lucian:'The Ship/The Wishes'(Sean McGrail in control of Olympias from Trireme Trust)

Suus omnes rostra ad me*

SHOCK AND OAR : PART I

 

The bronze fitting which was mounted at the bow of a trieres was there to damage an enemy ship and to guard the ship it was mounted on.

Digital model of Egadi 1 : Roman ram

 In English this is called a 'ram'.

This English term has a pro-active meaning as it does in the other Teutonic-influenced languages. The ram is an object which is meant to be propelled or driven forward and to impact on something. We have the battering ram used to open gates or to smash walls of a defended place. 

 

We have the hydraulic ram used in many pieces of machinery which is a tough head or bit which is pushed into a mould or target with tremendous force in order to cut or form it.

In ancient Greek the word used is ἐμβόλου-embolon. From the verb emballein which is to insert. This word is related to our modern 'embolism'. An embolism is an obstruction caused by an embolus which is, in turn something which blocks, intervenes or is inserted into something. It is also a wedge used to pry timber apart into planks. Very appropriate for something which shivers ship's timbers.

From BUZZLE.com

The Latin word used for the metal fitting at the bow of a warship is 'rostrum'. The word rostrum is still used today as it was by the Romans. It is the beak of a squid or the modified projecting mouthparts of the hemiptera. etc.

Eagle, Assassin Bug,Dolphin,Squid : all rostracising

 The 'rostrum' that modern speakers stand on is a descendant of the 'Rostra' which was a place in the Roman forum for public speaking decorated with the bow fittings of vanquished foes' ships.

Rostra in the forum at Rome

This Latin word implies that the bow-fitting is a characteristic feature of the warship. Part of its visual identity is the posession of the projecting 'beak'. Just as we may also think of a bird of prey as being characterised by its projecting, obvious, hooked beak.

OK. Talons too...

It is interesting that in the age when the Latins went to sea in a big way – the Punic Wars of the third and second centuries BC – they saw to it that ramming had declined as the main naval tactic. The Romans were learning to fight at sea after the great age of the trieres and against opponents who were proficient but not exactly 'rulers of the seas'. Also, the Roman experience of warfare at sea did not place the emphasis on ramming but on close combat using the ship as a platform for deck fighters.

Battle on land at sea

 There existed a fundamental difference in the mental concept of the ship's bow as a military weapon. The Greek mentality saw the embolon as something to be driven into the enemy. It was the weapon on the ship. 

 The Romans saw the rostrum as the finishing touch to the ship-of-war. The terrible beak on the Imperial Eagle which gave it its martial and scary character. Whereas the Greeks epitomised the warship as the delivery system for a weapon of impact, the Romans saw it as a vessel for carrying fighters which in its military incarnation had to have a beak to fit the part. 

Wall painting from Pompeii

 A Roman ship did not have to ram to be effective whereas a Greek trieres was nothing if it was not a ramming machine.

One can not have too many pictures of Olympias!

(* It's all beak to me. approx.)

A BEACH IS LIFE

In ancient naval battles commanders sometimes actually chose to run their ships in to the shore as a tactic. This seems, at first, rather puzzling. Why should ships throw away their mobility to fight ? How could they cast themselves ashore which is what good navigators try to avoid, isn't it?

'Time and tide wait for no ship'

Ancient galleys were built for speed. They did not carry large quantities of provisions and there was no space on board for cooking or sleeping. At a pinch men could eat bread dipped in olive oil while they rowed but the normal procedure was to eat ashore.

'Otter's noses in a bun-only 2 drachma!'

The stern of a galley curves steeply upwards and the hull draught is generally shallow. This means that such ships can easily drive up against a beach without becoming fast. With the use of an anchor to each side the ship can be secured against moving in the wave wash. The crew would then disembark via ladders set against the threnys. 

Æneas casually deserting Dido up his gangplank or 'apobathra'
Oops,, black sail and figure in background has helmet...
this is Theseus casually deserting Ariadne

When it was time to depart the crew could row away from the land. It has been suggested that ships could have carried wooden rails to allow them to be drawn completely out of the water on any shallow beach for maintenance but this was not the everyday occurrence of simply running in to shore for a meal break or overnighting.

How NOT to beach a galley - these will be here for some time...10years?.

An answer becomes more apparent when one considers the alternatives for a fleet which is either surrounded or outnumbered. Ramming tactics rely on getting around the enemy to deliver the deadly blow while safe from the target. Counter-tactics can be evasion or facing the enemy head-on when the rams of both neutralise each other. Should a fleet have a suitable beach to its rear it makes sense to back water and drive the ships in so that they form a bulwark of rams facing to sea. Any assault must now be a meeting of the ships' prows and a slugfest between epibatai. Generally, not so many epibatai were carried, 10 to 40, but a beached ship could also use the manpower of the rowers to fend -off attackers with poles or oars if nothing else.

If the shore was occupied by friendly forces then reinforcements could board the ships and add to their defence. A palisade could even be thrown around the beached ships producing an armed fort to defend the vessels.
The attacker would have to keep all his rowers at their station and if he could not board and take the beached ships he must attempt to get lines onto them and drag them to sea. An alternative was to disembark troops or call supporting forces and make an assault from the land.

In any event the beaching tactic was a good one to avoid rapid or certain defeat and gave the underdog a chance to save some of his ships or delay the inevitable so he could escape after dusk or save his manpower by disembarkation. The cost of a trieres was quite enormous and so both sides made great efforts to either capture enemy vessels or preserve their own. A trieres was not like a tank or destroyer – it was not a disposable artefact which was merely a means to allow soldiers to fight. Tanks or destroyers allowed men to attack the enemy but the loss of the machines was not of itself important. They could be replaced. Even the crews were relatively quickly trained. A trieres was a synthesis of ship-building skills, selected raw materials, sailors and soldiers which created a weapon of war, transport and power projection. It was replaceable but at great cost and effort. 

 A trieres cost 1 talent per month to keep in service. This is was enough to feed a family of four for 120 years or more at Athenian prices! To build a trieres cost a whopping 10 talents.

For food, Greece has got talents.

If a hard-pressed commander found he had a suitable shore to hand rather than the all-too-prevalent, deadly, rocky coastline around the Aegean then beaching was to be considered. Trieres could back at close to the speed they could advance and thus a ship could run for the beach, keeping its ram to the enemy.

If the ship must be given up at last then the crew could escape overland to man another ship and fight again.

Three hundred mens' fate and the time needed to create another such unit meant the loss of a single trieres would be keenly felt and so flight or beaching was a rational tactic for a fleet in danger. In a battle at sea a single successful ramming attack could seal the fate of a vessel and crew in a few minutes. Beaching gave the crew a fighting chance against superior numbers and would at least prolong the fight and give the crew a possible route to safety, and life.

Epibatai, beached and bleached.