Tobias Volckmer Astrolabe
Record status
Individual type · partial
Period
1594
This 1594 astrolabe, crafted from brass and measuring 200 mm in diameter, is signed by Tobias Volckmer of Brunswick. The instrument is distinguished by a mater structured as a flat disc lacking a traditional rim and the absence of movable plates.
The throne incorporates a circular table listing weekdays, their associated numbers, and planetary symbols, while a compass bowl is riveted to the back. The rete displays 30 Latin star names, later supplemented with Arabic names in a cursive script, and an ecliptic marked with zodiacal signs. The back of the instrument is densely engraved with multiple concentric circular scales including altitude, zodiacal, Gregorian and Julian calendars, lunar mansions, and winds.
A bottom segment houses planetary house sections, and a top quadrant accompanies the signature cartouche. The alidade and rule feature specific scales for declination and linear calculations, reflecting the instrument's complex design and intended use for detailed astrological and astronomical measurement.
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
- 1594
- Type
- Astrolabe
- Maker
- Tobias Volckmer
- Diameter
- 200 mm
- Provenance
- Bequeathed by Octavius Morgan
- Place recorded
- Germany
- Maker / attribution
- Tobias Volckmer
- Place of manufacture
- Brunswick
Design
- Visible features
- • Compass bowl riveted to the top throne • Signature cartouche reads 'THOBIAS VOLCKMER BRAUNSWEIGGENSIS FACIEBAT 1594' • Red pigment traces visible in the 1594 date and horoscope schema • Back scales include concentric Gregorian and Julian calendars
- Back Plate and Scales
- These include concentric scales for altitude, the zodiacal signs, and dual calendars for both the Gregorian and Julian systems. Additional circular scales represent the 28 lunar mansions, marked with their respective qualities, and the Latin names of the winds. The bottom section of the instrument's back is dedicated to planetary house sections. This area is divided into seven segments representing the planets, with each section subdivided into columns associated with specific times and planetary influence. A quadrant is positioned on the top right, while a signature cartouche and a shadow scale appear on the left.
- Construction and Mater
- The astrolabe is manufactured from brass and measures 200 mm in diameter. Its primary structure is defined by the mater, which takes the form of a disc without a rim. The outer perimeter of this mater is marked with a 360-degree altitude scale, numbered by 10 degrees, and a 24-hour scale. The throne serves as an extension of the mater, featuring a circular table that maps the Latin names of the weekdays to their corresponding numbers and planetary symbols. A compass bowl is mounted to the rear of the throne, providing a secondary utility for orientation.
- Signatures and Inscriptions
- The maker's mark is contained within a cartouche on the back of the instrument, reading 'THOBIAS VOLCKMER BRAUNSWEIGGENSIS FACIEBAT 1594'. It is reported that the date in this signature appears to have been filled with red pigment at some stage. The instrument contains further internal markings, such as a horoscope schema, which also retains traces of red. The rete features 30 Latin star names, which include corresponding magnitudes and planetary temperaments. In a separate, more cursive script, Arabic star names have been added to the rete, indicating later additions or revisions to the instrument's original engraving.
Identification
- Reference
- MLA 1888,12-1.280
- Inventory number
- MLA 1888,12-1.280
- 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 date 1594 appears to have been filled with red pigment after production
- Research required: The Arabic star names are described as being added in a different, more cursive script than the original markings