Roman shipbuilding and navigation
Where a modern ship is built by science, worked out with computers and precision instruments, a vessel in ancient Rome was closer to a craft, guided by guesswork, handed-down methods and personal experience. Seafaring did not come naturally to the Romans, a largely land-dwelling people; the shipwright's skills reached them from the nations they had defeated in battle, above all the Greeks and the Egyptians.
Only a handful of written records survive picturing Rome's ships, their sails and rigging included, while the wrecks archaeologists have dug up offer further hints about how such craft were made. These sources tell us that a Roman shipwright would finish the outer shell of the hull before turning to the frame and the rest. At first the planks of that shell were stitched together; from the 6th century BCE, though, they were joined by the mortise-and-tenon technique, in which each plank slotted into the next with no stitching required. The opening centuries of our own era then saw Mediterranean shipbuilders take up a different approach, one still used now, in which the frame went up first and the hull followed. Being more methodical, it cut the time a ship took to build quite sharply. Vessels of the size and sophistication Rome achieved with its great cargo ships and warships would not be matched anywhere until the 16th century CE.
A warship was made to be light and swift. Because it needed to work the waters close inshore, it carried neither ballast nor any surplus load, and its hull was built long and narrow. Damage rarely sent such a ship to the bottom; after a sea battle the disabled hulls would frequently be left floating on the surface. Mounted on the vessel was a ram of bronze, driven into the wooden hulls of the enemy to hole them or to snap their oars. Drawing on the wind through its sails as well as the muscle of its oarsmen, a warship could move at great speed. In time the Roman fleet grew into the mightiest in the Mediterranean, a dominance that led the Romans to speak of the sea as Mare Nostrum, 'our sea'.
Warships came in many forms. From the 7th to the 4th century BCE the leading one was the 'trireme', whose oarsmen sat at three heights, upper, middle and lower, with something like fifty men to a bank. Those placed lowest fared worst: penned beneath their fellow rowers, they took the water that came in through the oar-holes. It is worth remembering, too, that these men were not, as is commonly imagined, slaves; most were Roman citizens serving in the military. Larger craft carrying still more rowers eventually replaced the trireme.
Cargo ships, by contrast, were designed to carry a great deal of freight a long way at reasonable cost. Their hulls were broader, sheathed in a double layer of planking, and given a solid core so they sat steadily. Where a warship stayed shallow, the deep V-shaped underside of a merchantman kept it well below the surface and stopped it hugging the coast. A pair of large steering-oars was fitted on either side off the stern, each worked by a slender tiller bar running to a set of cables. From one to three masts carried big square sails, with a small triangular one at the bow. Merchant ships were rowed too, and keeping hundreds of oarsmen in step was no simple matter; to help them, an instrument would sound and the oars kept time to the music.
What these ships carried ranged from raw materials, bars of iron, copper, and blocks of marble and granite, to farm produce such as the grain grown in the Nile valley of Egypt. Rome under the Empire was, by ancient standards, an enormous city of roughly a million people, and goods from every quarter reached it through two harbours: Pozzuoli, west of the Bay of Naples, and the vast complex at Ostia, where the Tiber meets the sea. On nearing its destination a large merchant ship would be met, much as one is today, by a group of towboats that hauled it in to the quay.
How long a voyage took varied greatly from route to route. Roman navigation leaned not on refined instruments such as compasses but on experience, familiarity with a stretch of water, and close observation of nature. When the air was clear, Mediterranean sailors could usually keep the mainland or an island in view, which made finding their way far easier, and they steered by their position against one familiar landmark after another. If the weather closed in, or the land dropped from sight, they judged their heading from the pole star or, less reliably, from the midday Sun, reading direction, too, from the wind and swell. On the whole, sea travel in Roman days was not unlike our own, with sizeable ships crossing the water again and again to carry supplies from across the Empire.
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Question 1 - 5
Choose TRUE/FALSE/NOT GIVEN
1.
The Romans learned how to build ships from the peoples they had defeated.
True
False
Not given
2.
The wrecks of ships have told historians more about Roman shipbuilding methods than surviving texts have.
True
False
Not given
3.
Building the frame before the hull made ships faster to construct.
True
False
Not given
4.
Warships sank as soon as they were damaged in battle.
True
False
Not given
5.
Of all the rowers on a trireme, those positioned lowest had the easiest working conditions.
True
False
Not given