2.
Capua was not a port, and
portoria venalicium can not then refer to customs-duties, but must mean some other form of tax on merchandise, most probably a sales-tax of some kind. The town meant in the next clause cannot be identified, but it has been conjectured that it was a town which grew out of one of Hannibal's semi-permanent camps (Pliny,
N.H. III. 95). If so, it may have been a harbour, and
potorium would have its ordinary meaning of a
port-tax.
My translation takes it thus, and regards
Castrum as the shorter genitive of
Castra. Possibly we should read
Castrum Portorium (cf.
Castrum Novum in XXXVI. iii. 6), but this leaves
fruendum with no obvious construction. There is corruption in the text of the earlier part of the sentence, and perhaps it extends into this clause; in this case certainty as to the meaning is probably unattainable.