Agesilaos wrote:
......but a Mediterranean galley will be sunk by a storm of much less magnitude than either a Viking ship or a Mediterranean merchant ship.
That is a very debateable assertion. To begin with, whilst merchant ships (including viking 'knorrs' ) can sink, largely due to the weight of the cargo [The floor of the Mediterranean is littered with the remains of ancient merchant ships from a period of several thousand years], technically galleys rarely sink. Rather, they become waterlogged/flooded, but remain on the surface, which is one of the reasons galley wrecks are extremely rarely found......
...The galley has a high centre of gravity, which makes it unstable; its construction leaves it vulnerable to torque forces (they were long and thin and held in tension by what was , in effect an elastic band)
The stability of a vessel is not governed just by 'centre of gravity', rather the relationship between three points; centre of gravity, centre of buoyancy, and metacentre. Without wishing to get into technical details, it is the relationship between all three, called the metacentric height which governs stability. In any event, galleys have a low, rather than high centre of gravity.
Agesilaos refers to the tensioning device employed in galleys, but it was not "
in effect an elastic band". Just the opposite, in fact, not designed to stretch, but to provide rigidity. Nor does this tensioning device, which the Greeks called '
hypozoma/girdle' have any effect whatsoever on "torque", or twisting, forces (how could it?).
It was originally an Egyptian invention and its purpose was to minimise 'hogging' and 'sagging'. When a long vessel floats on waves at sea, it can be resting on a wave at the bow and another at the stern, with a trough in between. Naturally a long hull will tend to flex in the middle, called 'sagging'. Similarly if a long vessel is supported by a wave in the middle, the bow and stern will tend to droop, called 'hogging'. By tensioning a strong rope from bow to stern, until it is as rigid as an iron bar, the hull is strengthened to resist these fore-and-aft forces. This ingenious device allows galleys to be longer and lighter, yet stronger, than they otherwise would be. The effect is similar to that of a bowstring on a bow, which prevents the bow stave from flexing forward at all.
My point about 'biremes', and even smaller galleys such as 'pentekonters',is that they were still plentiful and useful in Alexander's day. And that technologically these oared ships were just as capable of crossing the Atlantic as other types, despite their limitations......though I agree with Agesilaos that they certainly wouldn't be one's first choice......
Nor should my being pedantic in correcting mistaken sweeping statements about the capabilities of ancient ships in general, and 'biremes' in particular be seen as somehow supporting Mr Hubbard's views, which can only be politely described as eccentric in the extreme, and as Agesilaos points out, incorrect and based on flawed logic, such as the 'ad ignorandiam' fallacy.
I was merely following up on Amyntoros' comments about the capabilities of ancient ships.....
..but perhaps to educate on the subject of sea transport in the late classical and early Hellenistic period.
As to "suicidal tendencies", there were many who thought Columbus and other later explorers were so inclined.......
Nor should it be forgotten that ancient Mediterranean seafarers ventured out into the wild oceans despite their fears,e.g Pytheas around Alexander's era venturing north to the British Isles and beyond to discover and describe the 'midnight sun' and arctic, or the Carthaginian Hanno the Navigator who may have circumnavigated Africa in the 5th C BC.......