The seats for the senators, arranged in the orchestra, were straight benches, placed at equal distances from each other, and were not fixed(589). The other benches, which were assigned to the knights and people, were semicircularly disposed around the circumference of the theatre, and spread from the orchestra to the rounded end of the building The extremities of the seats joined the orchestra, and they were carried one above another, sloping, till they reached the remotest part, and ascended almost to the ceiling. Thus the benches which were lowest and most contiguous to the orchestra, described a smaller circumference than those which spread more towards the outer walls of the theatre(590). Over the higher tier of seats a portico was constructed, the roof of which ranged with the loftiest part of the scene, in order that the voice expanding equally, might be carried to the uppermost seats, and thence to the top of the building(591). The benches, which were gently raised above each other, were separated into three sets or tiers: each tier, at least in most theatres, consisting of seven benches. According to some writers, the separation of these tiers was a passage, or gallery, which went quite round them for facility of communication; according to others, it was a belt, or precinction, which was twice the height, and twice the breadth of the seats(592). It would appear, however, from a passage in Vitruvius, that both a raised belt, and a gallery or corridore, surrounded each tier of seats(593). One of the precinctions formed the division between the places of the knights and those of the people(594). In a different and angular direction, the tiers and ranges of seats were separated by stairs, making so many lines in the circumference of the seats, and leading from the orchestra to the doors of the theatre. The benches were cut by the stairs into the form of wedges. The steps of the stairs were always a little lower than the seats; but the number of stairs varied in different theatres. Pompey’s theatre had fifteen, that of Marcellus only seven(595). As luxury increased at Rome, these stairs were bedewed with streams of fragrant water, for the purposes of coolness and refreshment. At the top of each flight of steps were doors called _vomitoria_, which gave egress from the theatre, and communicated directly with the external stair-cases(596).