Ancient World Merchant Ships
Construction
Below is a wreck of a Roman merchant ship from about 200 BC.
You can see the amphorae, probably filled with olive oil or wine.
Here they are building the replica of the Kyrenia II.
There is no real frame, the planks are fitted with tongue-like tenons and set into mortises, as the drawing below shows.
This type of construction is difficult and requires a high degree of skill, but is also very strong and light. The frame or ribs were added after the planking was set-up.
Rigging and Masting
Here we are on very uncertain ground. It seems reasonable that in Ursa's day, the use of blocks (pulleys) was unknown. The Egyptians never knew the block and tackle, but they were very tradition-bound and avoided change at all cost, even useful innovations. But the ancients were very clever in their own way so this does not preclude complex and sophisticated rigging. They would have known how to grease the yardarm halyard with goat or lamb fat and pass it over or through a pulleyless lead. The rest of the rigging can be worked without pulley blocks. The mast was held up by a heavy forestay attached to the head and running down to the prow. Back stays were set-up as well as athwartship shrouds.