Armillary sphere. The primary sphere consists of six metal rings. Between the primary sphere and the meridian ring, there is a movable metal semicircle fixed to the poles. A small yellow wooden square acts as a sliding indicator. Attached to the meridian ring, there is a graduated altitude quadrant with a yellow altitude quadrant with a yellow star as a sliding indicator. The sphere with its meridian ring is sustained by a metal arm attached to the pillar of a metal tripod stand. For full details about the cartography and construction of this armillary sphere please refer to the related publication.