He adds two hills, the Quirinal and Viminal; then in continuation he enlarges the Esquiliae, and takes up his own residence there, in order that respectability might attach to the place.

He surrounds the city with a rampart, a moat, and a wall: thus he enlarges the pomoerium.

They who regard only the etymology of the word, will have the pomoerium to be a space of ground without the walls; but it is rather a space on each side the wall, which the Etrurians in building cities consecrated by augury, reaching to a certain extent both within and without in the direction they intended to raise the wall; so that the houses might not be joined to it on the inside, as they commonly are now, and also that there might be some space without left free from human occupation.

This space, which it was not lawful to till or inhabit, the Romans called the pomoerium, not for its being without the wall, more than for the wall's being without it: and in enlarging the city, as far as the walls were intended to proceed outwards, so far these consecrated limits were likewise extended.
45.

The state being increased by the enlargement of the city, and every thing modelled at home and abroad for the exigencies both of peace and war, that the acquisition of power might not always depend on mere force of arms, he endeavoured to extend his empire by policy, and at the same time to add some ornament to the city.