Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
The Roman land-estates were, considered as larger holdings, uniformly
of limited extent. That described by Cato had an area of 240 jugera;
a very common measure was the so-called -centuria- of 200 -jugera-.
Where the laborious culture of the vine was pursued, the unit of
husbandry was made still less; Cato assumes in that case an area of
100 -jugera-. Any one who wished to invest more capital in farming
did not enlarge his estate, but acquired several estates; accordingly
the amount of 500 -jugera-,(2) fixed as the maximum which it was
allowable to occupy, has been conceived to represent the contents of
two or three estates.
