Ivory and silver diptych sundial
Record status
Individual type · partial
Period
circa 1600 ?
This unsigned ivory and silver diptych dial, catalogued by the Museum of the History of Science, Oxford (inventory number 83993), dates to circa 1600. The object measures 64 x 68 x 22 mm and is constructed from ivory leaves with silver components.
It features complex, multi-functional timekeeping surfaces. The outer side of the upper leaf originally featured a pin gnomon dial, though the pin is now missing. The inner side of the upper leaf contains a latitude scale, while the lower leaf houses a compass bowl and a horizontal string gnomon dial for common hours. The instrument is decorated with geometrical border designs and incorporates a painted compass card.
The dial is attributed to Spanish manufacture based on stylistic indicators, specifically the painting techniques applied to the compass card. It includes specific provisions for adjustment and storage, including a latitude adjustment arm and a dedicated compartment for the missing gnomon pin.
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 1600 ?
- Type
- Iberian diptych dial
- Origin
- Spanish
- Condition
- Pin missing from upper leaf gnomon
- Materials
- Ivory and silver
- Dimensions
- 64 x 68 x 22 mm
- Place recorded
- Spain
Design
- Visible features
- • Geometrical decoration borders the ivory leaves. • The compass card is painted in red, blue, and silver with a fleur-de-lis indicating north. • A latitude adjustment arm is positioned on the right side of the lower leaf. • The pin gnomon on the upper leaf is missing.
- Attribution and Origin
- The object is currently unsigned, providing no explicit information regarding its maker. The attribution to Spanish manufacture is derived from the stylistic treatment of the compass card. The estimated date of the dial is circa 1600. The museum documentation references scholarly work regarding the broader context of ivory sundials during the 16th and 17th centuries to assist in classification.
- Case and Exterior Features
- The diptych dial is constructed from ivory, with its structure comprising an upper and lower leaf. The overall dimensions of the object are 64 x 68 x 22 mm. The exterior surfaces of the leaves are ornamented with simple geometrical decoration along the borders. The upper leaf exterior originally featured a pin gnomon dial for common hours, marked 1 to 12 twice. This surface is decorated with green, red, and blue colors, with concentric circles appearing at the center. However, the pin itself is missing from the assembly. A storage compartment for the missing pin is located on the left edge of the lower leaf.
- Dial Functions and Internal Mechanisms
- The internal face of the upper leaf contains a latitude scale, marked on the right side in red. This scale ranges from 0 to 80 degrees, divided into 1-degree increments, with numerical markers at 5-degree intervals. The internal face of the lower leaf features a horizontal string gnomon dial for common hours, with markings reading 5 to 12 to 7. A compass bowl is integrated into the lower leaf, containing a paper compass card. This card is silvered and painted in red, blue, and silver, with a fleur-de-lis representing north. An arm for adjusting the instrument to the latitude is mounted on the right side of the leaf.
Identification
- Inventory number
- 83993
- 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 dating is prefaced with a question mark, indicating uncertainty.
- Research required: The attribution to Spanish origin is based on stylistic associations rather than a maker's signature or explicit provenance.
- Research required: The pin for the gnomon dial on the outer upper leaf is missing.