Nocturnal and sundial by Girolamo della Volpaia
Record status
Individual type · partial
Period
1567
This brass nocturnal and sundial, measuring 97 mm in diameter, is signed by Girolamo della Volpaia and dated 1567. The instrument is constructed from three superimposed circular disks, with a central sighting hole and a rotating pointer.
The nocturnal side features a zodiacal calendar scale and a volvelle consisting of two discs, the upper featuring 24 teeth and various scales, including a month scale and an inscription reading 'MEDIA NOX PER TOTVM ANNVM'. The second face functions as a sundial and quadrant, displaying an hour diagram for Italian hours, a 90-degree scale, and latitude information. The instrument includes a suspension mount resembling an astrolabe throne.
It is calibrated for a latitude of 43° 44', corresponding to Florence, and incorporates multiple inscriptions, including the signature in a scroll on the second face.
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
- 1567
- Type
- Italian nocturnal and sundial
- Maker
- Girolamo della Volpaia
- Place
- Florence
- Diameter
- 97 mm
- Provenance
- Dott. Filiberto Catinari, Fermo
- Place recorded
- Italy
- Maker / attribution
- Girolamo della Volpaia
- Latitude Calibration
- 43° 44'
Design
- Visible features
- • Central circular disc features a zodiacal calendar scale with 0° Aries at March 10 • Upper disk of the nocturnal is notched with 24 protruding teeth • Second face includes a quadrant scale of 90 degrees • Suspension mount designed as an astrolabe-style throne
- Nocturnal Construction
- The nocturnal side of the instrument consists of three superimposed brass disks of varying diameters. The central disk is marked with a zodiacal calendar scale, while the inner volvelle features two components: a lower disk with a 24-hour scale and an upper disk featuring 24 edge teeth. A pivoting long pointer marked 'HOROLOGIVM NOCTVRNVM' rotates around the central sighting hole. Various concentric scales are engraved on the upper disk, including a month scale and numeric sequences. An inscription, 'MEDIA NOX PER TOTVM ANNVM', is found in the fourth ring, with a matching 'MEDIA NOX' marker on the first disk to facilitate time calculation using the polar star.
- Mounting and Provenance
- The instrument includes a decorative suspension mount, or throne, integrated into the central plate, mirroring the style of an astrolabe. This component allows for the tool to be held or suspended during use. Records indicate the provenance of the instrument traces back to Dott. Filiberto Catinari of Fermo, acquired in 1992. The object is currently held in the collection of the Istituto e Museo di Storia della Scienza in Florence.
- Sundial Face and Quadrant
- The reverse side of the instrument serves as a sundial and quadrant, designed for latitudes 43° and 44°. It features a diagram for Italian hours, marked 9 to 24, and includes a 90-degree quadrant scale divided into single-degree increments. Surrounding the main diagram are calendar scales and a solar motion table labeled 'SOL IN SIGNO'. The signature of Girolamo della Volpaia is present in a scroll, alongside an inscription indicating the latitude and specific line markings for post-meridiem time.
Identification
- Inventory Number
- 3811
- 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 exact origin of the instrument beyond the attribution to Florence remains subject to historical research
- Research required: The precise function of the complex numeric inner scales on the nocturnal face is not fully detailed in the source