The Romans also demonstrated in their calendar, the implicit faith they
placed in this distinction of days. The fortunate days were marked in
white, and the unfortunate in black; of these were the days immediately
after the Calendae, the Nones, and the Ides; the reason was this: in the
363rd year from the building of Rome, the military tribunes, perceiving
the republic unsuccessful in war, directed that its cause should be
inquired into. The senate having applied to L. Aquinius, he answered,
"That when the Romans had fought against the Gauls, near the river Allia,
and had experienced so dreadful a defeat, sacrifices had been offered to
the gods the day after the ides of July, and that the Fabii having fought
on the same day at Cremera, were all destroyed." On receiving this answer,
the senate, by the advice of the pontiffs, ordered, that for the future
no military enterprise should be formed on the days of the calends, the
nones, or the ides. Vitellius having taken possession of the sovereign
authority on the 15th of August, and on the same day promulgated some
new laws, they were ill received by the people, because on that day had
happened the disastrous battles of the Allia and Cremera. There were other
days esteemed unhappy by the Romans, such as the day of sacrifices to the
dead; of the Lemuria; and of the Saturnalia, the 4th before the nones of
October; the 6th of the ides of November; the nones of July, called
Caprotinae; the 4th before the nones of August, on account of the defeat
at Cannae; and the ides of March, esteemed unlucky by the creatures of
Caesar.

In addition to these, were days which every individual considered
fortunate or unfortunate for himself. Augustus never undertook any thing
of importance on the day of the nones. Many historical observations have
contributed to favour these superstitious notions. Josephus remarks, that
the temple of Solomon was burnt by the Babylonians on the 8th of
September, and was a second time destroyed on the same day by Titus.