Armillary sphere brass with wood globe on brass stand, diameter of base 2 1/2 ins, outside diameter of meridian 4 1/2 ins, by Caspar Vopel of Cologne, German dated 1542
Made in 1542 by Caspar Vopel of Cologne, Germany, this brass armillary sphere encloses an early example of a terrestrial globe. A broad band, finely engraved with the star patterns of the Zodiac encircles the instrument. The armillary sphere is a demonstration device to explain the movements of the Sun, Moon, stars and planets across the sky. Its interlocking rings can be used to teach astronomical principles in same manner as a celestial globe or act as a model the universe. Based on the premise of an Earth centred universe, the armillary sphere was modified in the seventeenth century to teach the theory that the Earth orbits the Sun.