Besides an estate of 400, or after Augustus, of 1200 sestertia, no person was admitted to this dignity but one who had already borne some magistracy in the Commonwealth. The age is not sufficiently ascertained, probably not under 30.
The dictator, consuls, prætors, tribunes of the commons and interrex, had the power of assembling the Senate.
The places where they assembled were only such as had formerly been consecrated by the augurs—and most commonly within the city. They made use of the temple of Bellona, without the walls, for the giving audience to foreign ambassadors, and to such provincial magistrates as were to be heard in open Senates, before they entered the city, as when they petitioned for a triumph, and in similar cases. When the augurs reported that an ox had spoken, which we often meet with among the ancient prodigies, the Senate was presently to sit, sub dio, or in the open air.
The regular meetings (senatus legitimus) were on the Kalends, Nones, and Ides in every month, until the time of Augustus, who confined them to the Kalends and Ides. The senatus indictus was called for the dispatch of business upon any other day except the dies Comitialis, when the Senate were obliged to be present at the Comitia.
The Senate was summoned anciently by a public officer, named viator, because he called the Senators from the country—or by a public crier, when anything had happened about which the Senators were to be consulted hastily and without delay: but in latter times by an edict, appointing the time and place, and published several days before. The cause of assembling was also added.
If any one refused or neglected to attend, he was punished by a fine, and by distraining his goods, unless he had a just excuse. The fine was imposed by him who held the Senate, and pledges were taken till it was paid—but after 60 years of age, Senators might attend or not, as they pleased.
No decree could be made unless there was a quorum. What that was is uncertain. If any one wanted to hinder the passing of a decree, and suspected there was not a quorum, he said to the magistrate presiding, “Numera Senatum,” count the Senate.
The magistrate who was to preside offered a sacrifice, and took the auspices before he entered the Senate house. If they were not favorable, or not rightly taken, the business was deferred to another day. Augustus ordered that each Senator, before he took his seat, should pay his devotions with an offering of frankincense and wine, at the altar of that god in whose temple the Senate were assembled, that they might discharge their duty the more religiously. When the consuls entered, the Senators commonly rose up to do them honor.
The consuls elect were first asked their opinion, and the prætors, tribunes, &c. elect, seem to have had the same preference before the rest of their order. He who held the Senate, might consult first any one of the same order he thought proper.
Nothing could be laid before the Senate against the will of the consuls, unless by the tribunes of the people, who might also give their negative against any decree by the solemn word “Veto,” which was called interceding. This might also be done by all who had an equal or greater authority than the magistrate presiding. If any person interceded, the sentence was called “Senatus auctoritas,” their judgment or opinion.