‹‹‹ Vitr. 9.5.4 | Table of Contents | Vitr. 9.6.2 ›››
6I have described the true circuit of the heavens about the earth, the arrangement of the twelve signs, also that of the northern and southern constellations, because therefrom, from the opposite course of the sun through the signs, and from the shadows of gnomons at the equinoxes, are formed the diagrams of analemmata.
6I have shown how the firmament, and the twelve signs with the constellations arranged to the north and south of them, fly round the earth, so that the matter may be clearly understood. For it is from this revolution of the firmament, from the course of the sun through the signs in the opposite direction, and from the shadows cast by equinoctial gnomons, that we find the figure of the analemma.