‹‹‹ Vitr. 9.8.11 | Table of Contents | Vitr. 9.8.13 ›››
12On the lip of the large tympanum, which is fixed, are the figures of the celestial signs; above, is the figure of Cancer, and opposite to it, below, that of Capricornus. On the right of the spectator is Libra, on his left Aries.All the other signs are arranged in the spaces between these, as they are seen in the heavens.
12On the lip of the larger drum there are three hundred and sixty-five points, marked off at equal intervals. The rim of the smaller one has a tongue fixed on its circumference, with the tip directed towards those points; and also in this rim is a small opening, through which water runs into the drum and keeps the works going. The figures of the celestial signs being on the lip of the larger drum, and this drum being motionless, let the sign Cancer be drawn at the top, with Capricornus perpendicular to it at the bottom, Libra at the spectator’s right, Aries at his left, and let the other signs be given places between them as they are seen in the heavens.