BİRİNCİ FEN · İKİNCİ BÂB · SEKİZİNCİ FASIL · İkinci Madde
**Article Two**
Describes the directing sphere [504] and carrier globe of Mercury, along with its structure and motion.
O esteemed one! Know that astronomers have stated: The directing sphere of Mercury is encompassed by a common center-point globe and is the first of two eccentric globes. It encompasses the second of these spheres, and it is the second sphere of Mercury’s four spheres.
Because the directing sphere rotates, moving the center of the eccentric globe it contains from east to west, it is called the directing sphere. In this manner, other spheres with eccentric globes are situated within their common center-point spheres, just as this directing sphere occupies a place within its own common center-point globe.
The outward surface of the directing sphere touches the outward surface of the common center-point globe at a point known as the first apogee. The inner surface of the directing sphere, however, has touched the inner surface of the common center-point globe at a point known as the first perigee. The center of the directing sphere is displaced approximately six degrees from the center of the world towards the apogee point. In this manner, when the directing sphere separates from the common center-point sphere during its motion, two similar globes in the form of eccentric spheres also come into being to complete the other common center-point spheres. Following this, these second eccentric spheres are Mercury’s third sphere, which encompasses the directing sphere and carries the center of its epicycle. The carrier globe is situated within the directing sphere, just as the common center-point globe is within it.
The outward surface of the carrier globe meets the outward surface of the directing sphere at a point known as the second apogee, and its inner surface touches the inner surface of the directing sphere at a point called the second perigee. The center of the carrier globe is displaced three degrees from the center of the directing sphere and nine degrees from the center of the world in the direction of the apogee. As it continues its revolutions, when the carrier globe separates from the directing sphere, two globes of the form described above remain to complete it.
The planet Mercury appears in such a shape and appearance, arranged with such order and discipline, that it possesses two apogees and two perigees; these are considered as parts of the common center-point sphere, so they are named the “first apogee” and “first perigee” pertaining to the common center-point. They are also considered as parts of the directing sphere, so they are called the "apogee of the director" and "perigee of the director." The points of apogee and perigee on the common center-point globe are named the “first apogee” and “first perigee.” The points of apogee and perigee on the directing sphere are named the “second apogee” and “second perigee.” Because it is an absolute truth that each sphere has its own motion, and each sphere completes its rotation around its own center, axis, belt, and poles in this manner, Mercury’s directing sphere also rotates within its common center-point globe, around its own center, with its own motion, from east to west—contrary to the rising of the signs of the zodiac—turning Mercury's second apogee, completing a circuit in one solar year equivalent to the movement of the Sun.
The carrier globe of Mercury also rotates around its own center, with its own motion, from west to east—in accordance with the rising of the signs of the zodiac—rotating Mercury’s epicycle, just as other carrier globes are within the directing sphere. Half of its motion is contrary and reciprocal to the rising of the signs of the zodiac for the directing sphere, while the other half is equal to and in conjunction with the movement of the Sun; it remains in each sign for seventeen days, hesitates in some signs, stays for two months, and completes its circuit in one year. The center of Mercury’s epicycle, as is the case with Venus, always corresponds to the center of the Sun and never opposes it in its motion. Therefore, the planet Mercury does not stray more than a little over half the diameter of its epicycle from the path of the Sun; and its radius at its furthest average distance does not exceed twenty degrees. The truth is only known by God, exalted be He.