Astrolabe, Inventory 47901
Record status
Individual type · partial
Period
ca. 1350
This brass astrolabe, designated inventory number 47901, dates to approximately 1350 and is associated with Oxford. Unlike many European counterparts, this instrument is constructed from a single, thin plate, which serves as both the mater and the limb.
The womb is engraved for a latitude of 51°, matching that of Oxford. Due to the absence of a distinct limb or womb, the Y-shaped rete is riveted directly to the plate. An unusual design choice involves the calendar being placed on the outer band of the rete, the Tropic of Capricorn, rather than the back. The back of the instrument is entirely occupied by a quadrant, providing an increased scale for observational use. , and seventeen stars marked with flamant pointers.
It is currently held by the History of Science Museum, Oxford, having been acquired via Oriel College in 1924.
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. 1350
- Type
- Latin-inscribed astrolabe
- Stars
- 17
- Latitude
- 51°
- Material
- Brass
- Rete style
- Y-shaped
- Acquisition
- 1924
- Construction
- Single thin plate
- Place recorded
- Oxford
Design
- Visible features
- • Single thin brass plate construction with integrated limb • Calendar engraved on the Tropic of Capricorn band of the rete • Back face entirely occupied by a quadrant scale • Rete attached to the plate via a rivet
- Rete and Back Scales
- The rete features seventeen stars, identified by flamant pointers. A departure from the configuration of most period instruments, the calendar is located on the outer band of the rete at the Tropic of Capricorn. The zodiac labels are also engraved on the rete, utilizing Gothic numerals for the scales. The entirety of the back of the instrument is utilized for a quadrant, which allows for a larger scale than would be possible if the back also contained the calendar. The back displays three primary scales: a degree scale, a quadrant arc, and an unequal hours scale.
- Construction and Design
- The instrument is constructed from a single thin plate of brass, which serves as the base for all functional components. Because the design omits a traditional separate limb and womb, the outer edge of this plate serves as the limb, containing both an equal hours scale and a degree scale. The Y-shaped rete is mounted to this plate using a central rivet. This configuration is noted as unusual for European astrolabes of the period. The plate is dedicated to a latitude of 51°, suitable for Oxford, and carries almucantars, azimuths, and circles such as the equator and the Tropic of Capricorn. The lack of additional tympans reflects a specific focus on the local environment of the maker.
- Provenance and Historical Context
- The astrolabe is part of the collection of the History of Science Museum in Oxford, on loan from Oriel College since 1924. It is associated with the 14th-century intellectual environment in Oxford, specifically the 'Merton School' of astronomer-physicians. While it has been suggested that the object may have originated from the bequest of Simon Bredon, no definitive documentary proof confirms his ownership of this specific piece. The instrument is regarded as having been designed for active use by scholars rather than for display.
Identification
- Reference
- 47901
- Inventory number
- 47901
- 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 specific attribution to a Merton School fellow remains speculative
- Research required: The original ownership by Oriel College is described as presumed