On the Universe

OR ON COSMOGRAPHY. 15

of the fourth month; the shortest at the beginning of the tenth. The oblique orb declines from the equator as much as the boundary of the longest and shortest days does from the medium ones—namely, by 23 degrees. Thus, the two smallest circles near the poles are distant from the pole of the world, or the equator, as much as the oblique orb is distant from it, so that they are nothing other than a sign of the revolution of the pole of the oblique orb itself. The Meridian circle is the greatest, divided into 360 degrees, passing through the poles of the world and through the middle of the sky, placeable anywhere in the middle space between sunrise and sunset. When the Sun reaches this, it is noon by day; at night, it is midnight. It is divided into four times 90 degrees from the Horizon, which is also called the boundary, because it separates the part of the sky that is seen from the part not seen. This, however, also divides the equator into four times...