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
A similar indication of the rising importance of urban life in Rome is
presented by the great development of the urban police. To this period
probably belong in great measure the enactments under which the
four aediles divided the city into four police districts, and made
provision for the discharge of their equally important and difficult
functions--for the efficient repair of the network of drains small and
large by which Rome was pervaded, as well as of the public buildings
and places; for the proper cleansing and paving of the streets; for
obviating the nuisances of ruinous buildings, dangerous animals, or
foul smells; for the removing of waggons from the highway except
during the hours of evening and night, and generally for the keeping
open of the communication; for the uninterrupted supply of the market
of the capital with good and cheap grain; for the destruction of
unwholesome articles, and the suppression of false weights and
measures; and for the special oversight of baths, taverns, and
houses of bad fame.