James Hyslop reports... a 17th century Italian armillary sphere from Spain has just sold at Christies for a whopping £187,250. That's quite a result when set against the guide price which was (a by no means small) £30,000-£50,000 ($49,050-$81,750). All rings on the sphere were labelled in Latin with punched lettering, supported in the outer ring, divided 0°-90°-0°-90°, with punched numerals, an hour ring and s pointer to the top; the armillary was composed of two fixed meridian rings, equatorial, tropics and polar circles and a wider zodiac band which was divided on both inner and out surfaces. The outer surface was marked with engraved images for each house, whilst the inner rotating rings bore engraved image of sun and a crescent moon. The item stood 35.5cm (14inches) high on its tripod stand. The instrument was offered as part of the Manolo March Collection From Son Galcerán, Mallorca, sold in London on 28-29 October. Notably the sale was handled by the European Furniture, Decorative Objects and Early Sculpture department which may indicate a rival market to the scientific instrument collecting community when it comes to such items.

The armillary sphere is a demonstrational model of the universe. Composed of several rings (Armillae in Latin) and a band for the Zodiac, it represents the apparent movement of the celestial sphere around the Earth and marks the Sun's annual progress around the ecliptic. Their use can be traced back to antiquity and the handful of earliest extant examples date from the Middle Ages. But it was in the 16th and 17th centuries that their construction reached a peak and they became such iconic instruments of science. Elaborate and decorative examples were made for princely collections and they became symbolic of astronomy in paintings and engravings of the time. Find out more about Armillary Spheres in our A-Z of Scientific Instruments.