Astrolabe by 'Abd al-A'imma
Record status
Individual type · partial
Period
early 18th century
This early 18th-century brass astrolabe is attributed to the maker 'Abd al-A'imma of Iṣfahān. The instrument features a one-piece mater and limb construction with a degree scale on the limb.
The throne is of the indo-persian engraved type, featuring an integrated base embossed with an ornate foliate design, a round cross-section ring, and an omega-type shackle. The back of the instrument contains 16 distinct scales, including altitude, sine/cosine, cotangent, and shadow squares, alongside a serial number reading 'Opus twenty-four' and the maker's signature in a cartouche. The rete is of the foliate type and currently lacks star pointers.
It is held by a simple, recent replacement nut and bolt. The instrument includes four plates with latitudes ranging from 29° to 37° and a gazetteer containing coordinates for 32 cities.
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
- early 18th century
- Type
- Arabic-inscribed astrolabe
- Maker
- ‘Abd al-A’imma
- Place
- Iṣfahān
- Plates
- 4
- Material
- Brass
- Acquisition
- Purchased in 1944
- Serial Number
- Opus twenty-four
- Place recorded
- Iṣfahān
- Maker / attribution
- 'Abd al-A'imma
Design
- Visible features
- • Foliate engraved throne design • Ornate, foliate-style rete construction • Serial number 'رابع عشرون' (Opus twenty-four) inscribed on the back edge • Maker signature 'عبد الائمة' in a cartouche on the back
- Construction and Design
- The astrolabe is crafted from brass and features a one-piece construction for the mater and limb. The throne, identified as the indo-persian engraved type, is attached via an integrated base embossed with a foliate pattern. The instrument is suspended by a simple round cross-section ring and an omega-shaped shackle. A central tab for the tympans is positioned at the base, 180 degrees from the throne. The rete is of the foliate single-knob style, with the ecliptic broken at the Cancer sign and the horizontal support bar. , and it is secured to the instrument with a nut and bolt identified as a recent replacement.
- Scales and Inscriptions
- The back of the astrolabe is densely inscribed with 16 distinct scales arranged in concentric circles and quadrants. These include functions for altitude, declination, the azimuth of the Qibla, sine/cosine, cotangent, and shadow squares. Additional inner scales account for zodiacal signs, lunar mansions, faces, and triplicities. Inscriptions are present on the back edge, including the serial number designated as 'Opus twenty-four'. The maker's signature, reading 'Abd al-A'imma, is located within a cartouche on the instrument's back. The womb of the mater houses a gazetteer detailing coordinates for 32 cities, including Baghdad, Isfahan, and Mecca.
- Provenance and Acquisition
- The astrolabe is part of the Clay Collection, which was acquired by the History of Science Museum at the University of Oxford from R. S. Clay in 1944. R. S. Clay was an optical physicist who curated his collection through acquisitions from various London-based auction houses and dealers during the early 20th century. The object is catalogued under inventory number 43739 and accession number 1944-1/580. The collection primarily focused on optical instruments, with this piece representing one of two astrolabes acquired from Clay's holdings.
Identification
- Serial number
- رابع عشرون
- Inventory Number
- 43739
- 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 nut and bolt are documented as recent replacements
- Research required: The rete is noted to contain zero stars marked with bulb pointers