>The rule as cited says nothing about the size of individual ships; it's
>just a tax break for big business.
No, big business does not necessarily mean big ships. But there's more:
Greek and Roman Technology (1997):
1 medimnos (Greek) = 46 l
1 modius (Roman) = 8.7 l
Dionysius of Halicarnassus, Roman Antiquities 3.44.2-3:
"...merchant ships of a capacity up to 3000 enter at the mouth
of the river and arrive at Rome under oar or tow."
[larger unload in habour to river barges]
3000 modius = 26 tonnes -> 3000 medimnos = 138 tonnes. He was obviously
talking about medimnos, because he a) was a Greek and b) the other number
would not have made any sense.
There's more to come. I have another source that states that there were
about 60 to 80 ships of the Isis type (1200 tonnage, 2900 brutto register
tons). Have we now made it clear enough that the Roman ships were far
superior to MA and Viking ones?
Regards,
Erik Moeller