Diptych Dial, circa 1620
Record status
Individual type · partial
Period
circa 1620
This diptych dial is attributed to Thomas Tucher, dating to circa 1620, Nuremberg. The instrument is constructed from three layers of ivory, with two folding leaves, creating a double diptych configuration with brass components.
It incorporates a wide array of timekeeping and astronomical features, including a universal equinoctial dial, a polar dial, a lunar volvelle with an aspectarium, and a conversion table for Italian and Babylonian hours. Decoration consists of polychrome foliate and floral motifs. The instrument also features an integrated compass with magnetic deviation and a list of fifteen cities with their respective latitudes. Dimensions are 110 x 87 x 20 mm.
The object includes specific brass plate covers, one of which conceals earlier ivory engravings. The dial currently exhibits signs of wear, including missing components such as bun feet, a wind vane, and a missing pin for the polar dial, while the compass glass is cracked.
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
- circa 1620
- Type
- Nuremberg diptych dial
- Maker
- Thomas Tucher
- Material
- Ivory and brass
- Maker's Mark
- Snake
- Configuration
- Double diptych dial
- Place recorded
- Nuremberg
- Maker / attribution
- Thomas Tucher
Design
- Visible features
- • Polychrome floral and foliate decoration • Compass with magnetic deviation and snake maker's mark • Visible latitude scale on the universal equinoctial dial component
- Condition and Marks
- The object bears the maker's mark in the form of a snake, punched twice within the compass housing. The instrument shows several signs of previous use and partial loss. Notably, two of the four bun feet on the brass plate side are missing. Additional damage is observed in the compass, where the protective glass is cracked. Furthermore, a wind vane on the leaf featuring the wind rose is absent, and the polar dial on the corresponding leaf is missing its central pin, limiting its current functionality as a diagnostic instrument.
- Construction and Composition
- The object is constructed of three layers of ivory, featuring two folding leaves that expand the functional space of the instrument. The core structure is augmented by brass components, including plates, volvelles, and a compass assembly. Dimensions are recorded as 110 mm by 87 mm by 20 mm. On one leaf, a brass plate covers the exterior, featuring a pierced lunar volvelle and aspectarium. Evidence of underlying ivory engravings suggests the brass plate was applied to cover previous work. Decoration across the ivory surfaces is executed in polychrome, featuring birds, flowers, and foliage in the spandrel spaces and remaining open areas.
- Timekeeping and Astronomical Features
- The dial integrates multiple horological functions. One side functions as a standard diptych dial, while another hosts a universal equinoctial dial adjustable for latitudes between 0 and 90 degrees. Further features include a polar dial on an inner leaf, which provides sunlight duration information and solar declination via zodiac symbols. A conversion table on one leaf allows for the translation of Italian and Babylonian hours. Below the compass, which displays cardinal points and magnetic deviation, another polar dial calibrated for latitude 45 degrees provides additional temporal data, including Italian and Babylonian hour scales and day/night length indicators.
Identification
- Inventory Number
- 73044
- 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: Missing wind vane and polar dial pin
- Research required: Cracked compass glass
- Research required: Two missing bun feet