Astrolabe by Georg Hartmann
Record status
Individual type · partial
Period
1527
This brass astrolabe, measuring 162 mm in diameter, was made by Georg Hartmann in 1527. The instrument features a mater constructed from two soldered layers of brass, comprising the plate and the combined limb and throne.
The throne is decorated with scrollwork and flowers, while the suspension consists of a saddle-like shackle and two rings. The face includes concentric degree scales and hour numbering. Three plates are present, engraved with various lines for coordinates, including tropic lines, equator lines, and latitude indicators for Nuremberg and other locations. The back of the mater includes a degree scale, zodiacal signs, a calendar scale, and a central double shadow square.
A signature and date are engraved within the shadow square, alongside the Laudian coat-of-arms on the top half. The rete, pin, wedge, rule, and alidade are missing from the instrument.
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
- 1527
- Type
- Nuremberg astrolabe
- Maker
- Georg Hartmann
- Diameter
- 162 mm
- Signature
- GEORGIVS HARTMAN NOREMBERGE FECIT ANNO M D XXVII
- Place recorded
- Nuremberg
- Place of origin
- Nuremberg
- Maker / attribution
- Georg Hartmann
Design
- Visible features
- • Darkened exterior surface finish • Saddle-like suspension shackle • Engraved signature and date on the back • Laudian coat-of-arms on the reverse
- State of Preservation
- The instrument is incomplete, with several key functional components missing. Specifically, the rete, pin, and wedge are absent from the central assembly. Additionally, the rule and alidade, which are necessary for taking measurements using the instrument, are not present. Despite the absence of these parts, the primary brass structure of the mater and the three plates remain intact. The engraved details, including the latitude lines, zodiacal scales, and signature, remain visible, and the overall dimensions of the 162 mm diameter frame are maintained.
- Provenance and History
- The astrolabe was documented in England by the seventeenth century, where it entered the collection of Archbishop Laud. This ownership is confirmed by the presence of his coat-of-arms on the back of the instrument. The archbishop's arms are those of the archbishopric of Canterbury combined with his own heraldic devices. The instrument currently exhibits a darkened, black exterior surface. This coloration is suspected to be a result of long-term exposure to atmospheric conditions, specifically the environment of a nineteenth-century gas-lit room. While the exterior and some internal areas show this effect, the inner surfaces of the plates remain unaffected by this process.
- Construction and Design
- The astrolabe is composed of a mater formed from two soldered brass layers, creating the base for the limb and the throne. The throne features scrollwork and floral decoration, while the suspension system uses a shackle and two rings. The limb is divided into two concentric circles, with the outer circle containing degree markings and hour divisions, and the inner circle featuring quadrant divisions. The instrument includes three internal plates engraved with meridians, equator lines, and tropic markers. These plates also display latitude engravings, including specific markings for Nuremberg at 49 degrees 27 minutes. The rear of the mater features additional circular scales for zodiacal signs and a calendar, surrounding a central shadow square and the Laudian coat-of-arms.
Identification
- Inventory number
- 38642
- 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: Cause of the blackening is attributed to possible nineteenth-century gas-lit conditions
- Research required: Exact extent of missing components beyond the rete, pin, wedge, rule and alidade