Numa Pompilius

postea sive a Numa, ut ait Fulvius, sive, ut Iunius, a Tarquinio XII facti sunt menses et dies CCCLV, quamvis luna XII suis mensibus CCCLIIII dies videbatur explere. sed ut dies unus abundaret, aut per inprudentiam accidit, aut, quod magis credo, ea superstitione qua inpar numerus plenus et magis faustus habebatur.

Later there came to be twelve months and 355 days. Fulvius says that Numa did this, and Junius that Tarquin did. Yet the moon seemed to complete its twelve months in 354 days. The one extra day was either a mistake or, as I rather believe, came from the superstition that held an odd number to be full and luckier.

Sequitur Iulius qui, cum secundum Romuli ordinationem, Martio anni tenente principium, Quintilis a numero uocaretur, nihilo minus tamen etiam post praepositos a Numa Ianuarium ac Februarium retinuit nomen, cum non uideretur iam quintus esse sed septimus. sed postea in honorem Iulii Caesaris dictatoris, legem ferente M. Antonio M. filio consule, Iulius appellatus est, quod hoc mense a. d. quartum Idus Quintilis Iulius procreatus sit.

Next comes July. Under Romulus's plan, when March began the year, it was called Quintilis from its number, "fifth." It kept that name even after Numa put January and February in front of it, though it no longer seemed to be the fifth month but the seventh. But later it was named Iulius in honor of Julius Caesar the dictator, under a law proposed by the consul Mark Antony, son of Marcus. The reason was that Julius had been born in this month, on the fourth day before the Ides of Quintilis.

Sed secutus Numa, quantum sub caelo rudi et saeculo adhuc impolito solo ingenio magistro comprehendere potuit, uel quia Graecorum obseruatione forsan instructus est, quinquaginta dies addidit, ut in trecentos quinquaginta quattuor dies, quibus duodecim lunae cursus confici credidit, annus extenderetur.

Then came Numa, and he added fifty days. He did this as far as he could understand things, in a rough land and an age still unrefined, with only his own mind for a teacher. Or perhaps he had learned from the observations of the Greeks. With these days the year was stretched to 354 days, the time in which he believed the moon completes twelve cycles.

Numae ordinationem finitimi mox secuti totidem diebus totidemque mensibus, ut Pompilio placuit, annum suum computare coeperunt, sed hoc solo discrepabant, quod menses undetricenum tricenumque numero alternauerunt.

The neighboring peoples soon followed Numa's plan. They began to count their year with as many days and as many months as Pompilius had chosen. They differed only in that their months alternated between 29 and 30 days.

paulo post Numa in honorem imparis numeri, secretum hoc et ante Pythagoram parturiente natura, unum adiecit diem, quem Ianuario dedit, ut tam in anno quam in mensibus singulis praeter unum Februarium impar numerus seruaretur. nam quia duodecim menses, si singuli aut pari aut impari numero putarentur, consummationem parem facerent, unus pari numero institutus uniuersam putationem imparem fecit.

A little later Numa added one more day in honor of the odd number, a secret that nature revealed even before Pythagoras. He gave the day to January, so that the year and every month except February would have an odd number of days. If all twelve months had an even number of days, or all had an odd number, the total would be even. So one month with an even number made the whole count odd.

cum ergo Romani ex hac distributione Pompilii ad lunae cursum sicut Graeci annum proprium computarent, necessario et intercalarem mensem instituerunt more Graecorum.

Under this arrangement of Pompilius the Romans counted their year by the course of the moon, as the Greeks did. So they also had to set up an intercalary month, after the Greek custom.