Brass Astrolabe, late 14th or early 15th century
Record status
Individual type · partial
Period
late 14th or early 15th century
This brass astrolabe, inventory number 54330, is dated to the late 14th or early 15th century and is attributed to Paris. The instrument features a three-lobed throne with an integrated base and an omega-type shackle.
Its construction includes a two-piece soldered mater and limb. The back displays five distinct scales, including degree, zodiacal signs, calendar, unequal hours, and a shadow square. The rete, attached via a pin and wedge, accommodates 17 stars marked with flamant pointers and an ecliptic scale. It includes four plates for latitudes ranging from 38° to 60°. The double-ended alidade is counter-changed. The front of the throne is engraved with a gothic 4 or similar mark.
Formerly part of the Henri Michel collection, the object was acquired by the History of Science Museum in Oxford via the Billmeir Collection in 1957.
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
- late 14th or early 15th century
- Type
- Latin-inscribed astrolabe
- Material
- Brass
- Acquisition
- Presented by J.A. Billmeir in 1957
- Throne type
- Three-lobed
- Place recorded
- France
- Place of Manufacture
- Paris (?)
- Number of stars on rete
- 17
Design
- Visible features
- • Engraved gothic numeral 4 or monogram on the throne • Flamant pointers used to indicate stars on the rete • Inscription PIS on the 49° latitude plate • Double-ended counter-changed alidade
- Scales and Engravings
- The back of the astrolabe is equipped with five functional scales for astronomical calculation: a degree scale, a zodiacal signs scale, a calendar scale, a scale for unequal hours, and a shadow square. The zodiacal signs are divided into 10-degree increments, and the calendar follows a month-based cycle. A small mark resembling a gothic 4 or a monogram is engraved on the throne. Additionally, an inscription 'PIS' is found on the plate corresponding to 49° latitude.
- Provenance and Historical Context
- This astrolabe entered the museum's collection in 1957 as a gift from J.A. Billmeir, who had previously acquired it as part of the collection of Henri Michel from Brussels. The historical associations of the instrument have been a subject of scholarly curiosity, particularly concerning the potential original ownership. Beyond its probable Parisian origins, the existence of a specific latitude plate for 51° 40' indicates that the instrument may have been utilized or owned in the Netherlands, Germany, or Oxford, suggesting a history of movement across European centers of learning.
- Construction and Component Details
- The instrument is fabricated from brass and features a three-lobed throne with an integrated base. The ring attached to the throne is of a simple, round cross-section, while the shackle is of the omega type. The mater and limb are constructed from two soldered pieces, with the limb featuring a concentric degree scale numbered every 15 degrees. The rete is designed with an indicator-line structure and a broken meridian band below the ecliptic. It features 17 stars, each indicated by a flamant pointer, and is fixed using a pin and wedge mechanism. The device includes four distinct plates with latitudes varying between 38° and 60°.
Identification
- Inventory Number
- 54330
- 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 nature of the mark on the throne (monogram, maker's mark, or symbol) remains unidentified
- Research required: The interpretation of the PIS inscription as a name (Thomas de Pisan) is contested by the museum