A MAGHRIBI ASTROLABE WITH TINNED RETE
A MAGHRIBI ASTROLABE WITH TINNED RETE
A MAGHRIBI ASTROLABE WITH TINNED RETE
A MAGHRIBI ASTROLABE WITH TINNED RETE
3 More
A MAGHRIBI ASTROLABE WITH TINNED RETE

18TH CENTURY

Details
A MAGHRIBI ASTROLABE WITH TINNED RETE
18TH CENTURY
the brass mater and limb riveted together, integrated undecorated throne with ring and shackle, degree scale to limb 0-360° divided by 1° marked by 5°, the inner mater marked with eight engraved concentric circles and tinned, the reverse engraved with concentric scales, from the outer perimeter in: two altitude arcs to upper left and right quadrants 0-90° divided by 1° marked by 5°; zodiacal scales 0-30° divided to 1° with numbered subdivisions by 5°; calendar with western months, divided to days of the year, marked in 6 groups for each month (5 for February); central area with two projections of unequal hours, each 1-6; shadow square divided every 12 marked in groups of 3.
The plate engraved on both sides with stereographic projections for latitudes for 28° and 30°, altitude circles every 3° and azimuth arcs every 10°, circles for Cancer, Equator and Capricorn, payer lines and horizon.
The brass rete tinned, with hook pointers for 26 stars, all but one named, the eclitpic with labelled zodiac divided to 6°, three raised turning handles. alidade with pinhole sights, pin and horse.
5¼in. (13.4cm.) diameter
Literature
King, D. 'On the History of Astronomy in the Medieval Maghrib', in Études d'histoire des sciences arabes, Abattouy, ed., 2007, pp. 175-218

If you wish to view the condition report of this lot, please sign in to your account.

Sign in
View condition report

Lot Essay

The tinning to this astrolabe is a feature very rarely seen on Islamic scientific instruments, but is more common on other brass works of art. By the nature of their regular use, rubbing to the tinned surfaces is likely and it is possible that other brass astrolabes have lost such a surface over the years.
The star pointers to the rete, shaped like a shepherds hook, are based on a traditional 18th century Maghribi near-symmetrical pattern: see two astrolabes held at the Museum of the History of Science in Oxford by al Battuti, Inv. No. 52713 and Inv. No. 51459, and another unsigned Inv. No. 52713. Though unsigned, the mater of this astrolabe is very finely engraved and still has traces of tinning to the outer brass surfaces. It is possible that it dates from earlier in the 18th century than the tinned plate, rete and alidade.
The importance of Islamic science in the medieval world is well documented, but interest in astronomy and astrology continued for centuries thereafter. In particular traditions of instrument making carried on, best exemplified by fine astrolabes such as the current lot. Often described as an analogue celestial computer, the planispheric astrolabe is an instrument that enables its user to carry out calculations to determine the time of day or night based on the observation of the Sun and Stars.

More from Travel, Science and Natural History

View All
View All