Peurbach (1474) 1R

NEW THEORICAE OF THE PLANETS
BY THE VERY FAMOUS ASTRONOMER GEORG PEURBACH
ON THE SUN
The sun has three orbs, separated from each other everywhere but contiguous with each other. The convex surface of the outermost of these is concentric with [the center of the] world; the concave [surface] is eccentric [with the center of the world]. The concave surface of the innermost [orb] is concentric [with the center of the world], but the convex [surface] is eccentric. The third [orb] is situated between these. Both its concave and convex [surfaces] are eccentric to the [center of the] world. Now an orb with its center at the center of the world is said to be concentric with the world. But an eccentric is an orb with a center other than the center of the world. And thus the first two orbs are complementary eccentrics, and they are called ‘the orbs carrying the aux of the sun.’ For by their motion [the position of] the aux of the sun is changed. But the third orb is simply eccentric, and it is called the orb carrying the sun. For the body of the sun is attached to it and is moved by its motion. These three orbs have two centers.
THEORICA OF THE SUN