Ancient Greek Ship Design
Throughout antiquity, there were two main strands in Greek hull design: that for war and ceremonial ships, ands that for commercial ships carrying cargo. Accounts of these ships have tended to concentrate on military ship design.
Homer describes in the second book of the Iliad how 1186 Greek ships were used for the transport of the Greek army to Troy. The reason for this expedition was probably to obtain the control of the passage to the black sea from Troy (a city which was destroyed by the Greeks in 1180 BC ). Among the ships Homer describes that each of the 50 Boetian Ships carried 120 warriors. The ships were covered by a black paint (probably pitch for the protection of the wood) and had a single sail.. The anchor was a single heavy stone.
The Homeric ship or galley had a sharp black hull, but was not as yet provided with a ram. The keel was probably first laid upon short upright banks of timber, laid level at suitable intervals. From the keel sprang the stem-post , carried upward to a good height, as was also the stern-post. The sides were held together by the thwarts , which formed the seats for the oarsmen. At the bow was a raised platform or deck , on which stood the fighting men of the ship; and there was a similar deck at the stern, on which the arms were kept, and under which there was room for stowage. The length of the fifty-oared galley is calculated to have been about 31m from stem to stern, with a breadth amidships of 3.5m
The galley was propelled by oars and sails together, the mast being raised or lowered as stated above. When raised, it was held in a sort of box , and kept in its place by forestays . When lowered it rested on a sort of crutch. There was also a backstay . The sail was hoisted on a yard having braces and halyards. The sails were square in shape and white in colour. The ropes were of thong; but larger cables were made of byblus, occasionally of hemp or rushes . The ship was steered by paddles. The oars were of pine-wood, the parts being the handle and blade . The oars were fastened to thowls by thongs, and when not in use were drawn in, leaving the blade projecting.
The master of the ship had his place on the forward deck. At times a long pole for pushing was used as an instrument of propulsion. There were up to 118 oarsmen according to Homer.
Homer describes how Odysseus built his own Ship, Argo, by cutting 20 trees. “Argo” was the boat that was taken on a voyage between Greece and Georgia in the quest for the Golden Fleece. Argo was reconstructed in 1971.
Although Argo was square rigged, with a single sail she had a long narrow hull (12 m long at deck level but only 2m beam) designed to be rowed, and there was little space provision for anything but th 20 oarsmen, as can be seen from the deck plan below:
This would not be a very attractive design, capable of encouraging modern-day maritime tourists want to make voyages aboard her, as she did not offer her passengers (who would all have to row the boat) much variety or comfort.
Argo’s hull profile was long and shallow (only 1 metre draft), which meant she could be beached, as she had no keel protruding downwards. Lack of a deep keel, or larboards, would result in in poor performance (drift to lee) when sailing into the wind, but this did not matter as Argo’s propulsion was by sail only with a following wind, otherwise it was by oar-power. There was no rudder fitted, instead a steering oar was employed each side at the stern. The hull was round bilged, with a long bow protrusion at the front extending under the waterline. This made Argo easy to board at the bow when beached.
Ancient commercial boats differed from boats like Argo in that they would be sailed by a crew of only 3-4 sailors, and so oarsmen and rowing stations were dispensed with and propulsion was by sail alone, which is why over the last 2 millennia, their sail plans evolved from square rig through lateen rig, and into fore-and-aft rig, with better performance when sailing into the wind, but also require a deep keel or, alternatively, larboards to be fitted to the hull.
Before the invention of the trireme the standard warship was a single-banked ship with a crew of 50 rowers (25 a side), called a pentekonter (and also the triakonter with 30 rowers). With a distance of around 1 m between the rowers the length of the pentekonter was around 30 m. There is a need for more rowers but estimates show that the ship length was close to the critical length of 35 m that was possible by the materials and technology used. The width of the ship was around 4m. Two versions were used were the undecked open vessels (afrakta) and the vessels with a deck (katafrakta). The rowers were actually warriors and the ship was used for troop transport (like that to Troy).
Biremes and Triremes with Rams
To increase momentum meant more rowers, to reduce extra size and weight meant putting oars and oarsmen over one another. This leads to the bireme (or dieres) (probably introduced by the Erythraeans). This raises the centre of gravity and threatens the stability of a very low-draughted ship. The ingenious solution has only recently been explained and proved. The large number of rowers needs also a synchronization and thus a special training and this changed also the war tactics as the rowers were not professional warriors. It seems strange to reduce the number of warriors but the bireme and trireme were faster than the pentekonter and with their ram (a bronze tipped projection from the bow (front) of the ship) it was much easier to destroy a pentekonter even if it had much more warriors.
The Ram on the reconstruction of the Trireme “Olympias”
The trireme was probably the most formidable ship ever designed for fighting with a ram. Functioning similarly to a modern frigate, the trireme represented the best that naval technology has to offer at that time, one of the most dangerous and effective weapons. The Greeks used the ram to punch a hole in an enemy ship below the waterline and sink it. This tactic was known as diekplous. The trireme when dressed for battle was nothing else but a stripped-down water-borne projectile, propelled by human muscle power.