Astrolabe, ca. 1250
Record status
Individual type · partial
Period
ca. 1250
This brass astrolabe, identified as inventory number 49033, is attributed to Spain circa 1250 and is maintained in the History of Science Museum, Oxford. It features a simple throne with an integrated base and an omega-type shackle.
The instrument includes a riveted mater and limb, and a rete of the indicator-line type containing 21 stars marked with dagger pointers. The zodiacal signs are engraved on the rete. Four plates are provided, covering latitudes from 30° to 60°. The back of the instrument features unfinished scales, including a shadow square, a calendrical table based on the 28-year solar cycle, and zodiacal and calendar scales. The double-ended, counter-changed alidade is original but has broken tips.
The instrument was presented to the collection by Lewis Evans in 1924, having been purchased from dealer Percy Webster in 1911. It is considered an early Western example.
Evidence at a glance
- Linked sources
- 1
- Photograph views
- 1
- Catalogue references
- 0
Counts describe this entry’s documentation, not authenticity, rarity or completeness. Photographs may show one specimen; check each caption and licence.
Technical characteristics
- Date
- ca. 1250
- Type
- Latin-inscribed astrolabe
- Place
- Spain (?)
- Material
- Brass
- Star count
- 21
- Acquisition
- 1924
- Place recorded
- Spain (?)
- Plate latitudes
- 30°0' to 60°0'
Design
- Visible features
- • The alidade exhibits broken tips at both ends. • The back scales, including the shadow square and calendrical table, remain incomplete. • The rete features star names engraved alongside dagger-shaped pointers. • The instrument is held together by a pin and horse.
- Scales and Markings
- The back of the astrolabe contains four distinct scales: zodiacal signs, a calendar, a shadow square, and a solar cycle. These elements are currently unfinished. The shadow square lacks both labels and numbers, and the calendrical table, which is based on a 28-year solar cycle, remains incomplete. The zodiacal signs and the calendar are arranged in circular patterns. The limb features a degree scale for measurement, though these degrees are not numbered. The womb of the instrument is inscribed with specific latitude details, and the almucantars and azimuths are divided every 5 degrees, represented by plain lines.
- Construction and Design
- The astrolabe is constructed primarily from brass, featuring a simple throne attached with an integrated base and an omega-type shackle. The mater and limb are joined via a riveted construction, with the notch for plate tabs positioned at the throne. The design incorporates a rete of the indicator-line type, which is secured to the main body by a pin and horse mechanism. The rete displays 21 stars, each indicated by a dagger pointer, and features a labelled zodiac. The four accompanying plates provide latitude ranges between 30° and 60°. The alidade is a double-ended, counter-changed component. While it retains its original form, the tips have suffered damage and are broken, and the sighting vanes include notches of an indeterminate function.
- Provenance and Historical Context
- This instrument was presented to the Oxford collection by Lewis Evans in 1924, accessioned under number 1924-0/2090. Evans had acquired the piece in 1911 through Percy Webster, a London-based dealer. Although the object displays Hispano-Moorish stylistic influences, it is not signed or dated. Research suggests that the inclusion of specific plates for 48° and 52° latitudes indicates that it may have originally been intended for use by an individual located in Paris or London.
Identification
- Reference
- 49033
- Inventory number
- 49033
- Source note
- Facts transcribed from the linked source listing or collection record. Attribution and specifications are source-reported and have not been independently authenticated.
Catalogue references
No catalogue numbers recorded. Numbers are only published once transcribed from a verified edition of a standard catalogue — they are never inferred.
Research required
- Research required: The manufacture is tentatively attributed to Spain with uncertainty.
- Research required: The original purpose or intended user location in Paris or London remains speculative based on plate latitudes.
- Research required: The functionality of the notches on the alidade sighting vanes is unidentified.