Skip to content
The Encyclopedia of Horology

Tool · Latin-inscribed astrolabe

Astrolabe

Partially verified

This brass astrolabe (inventory number 45307), dated to approximately 1300, is attributed to Spain. The instrument features a one-piece mater and limb construction. The throne follows a moorish-arch style, designed as a fleur-de-lis flanked by crouching lions. The back of the instrument incorporates four distinct scales including a degree scale, zodiacal signs, calendar, and a shadow square. The rete consists of an indicator-line type design, marked with 25 stars identified by dagger pointers, featuring zoomorphic bird star pointers for select stars such as alcair, alferat, and algorab. The rete also displays zodiacal labels. The instrument is equipped with original double-ended, counter-changed rules and is attached with a pin and horse. The piece was presented by J. A. Billmeir in 1957 and was previously held by the collector and dealer Nicolas Landau of Paris.

Front view of the brass astrolabe showing the rete, throne with lion motifs, and rule.
Front view of the brass astrolabe showing the rete, throne with lion motifs, and rule. — History of Science Museum, University of Oxford. Rights pending — permission not yet requested. Original source

Catalogue identity

Source
www.mhs.ox.ac.uk
Category
Tool · Latin-inscribed astrolabe
Maker / attribution
Not established
Reference
Not recorded
Catalogue / lot identifier
45307
Source-reported date
ca. 1300
Source-reported place
Spain (?)

Source-reported attribution and specifications are not independent authentication. A listing does not establish present ownership, current display, availability or permission to reproduce.

Object description

Construction and Design

The astrolabe is manufactured from brass and features a integrated base construction for the throne. The throne itself is of a moorish-arch type, incorporating a fleur-de-lis motif with crouching lions engraved on both the front and back. The ring connected to the shackle is a simple circular cross-section piece.

The mater and the limb are made in a single-piece construction. The limb contains circular, concentric scales for degrees ranging from 0 to 360 and an equal hours scale for marking the times of day from 1 to 12.

Evidence for this section
  • “The throne is of the moorish arch type made of brass attached with integrated base”
  • “The mater and limb are of one-piece construction.”

Rete and Celestial Markings

The rete is designed as an indicator-line type featuring moorish-arch style bases for the star pointers. It displays 25 stars marked with dagger pointers. Certain stars are specifically indicated with zoomorphic bird-shaped pointers, including alcair, alferat, venterceti, algorab, elfeta, and razalage.

The ecliptic is marked with zodiacal signs, including Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. The rete is attached to the main body via a pin and horse arrangement.

Evidence for this section
  • “The rete contains 25 stars. The rete contains zoomorphs: bird star pointers for the following stars: alcair, alferat, venterceti, algorab, elfeta, razalage”
  • “The rete is attached using a pin & horse.”

Provenance and Back Scales

The back of the instrument contains four primary scales: degree, zodiacal, calendar, and a shadow square. The shadow square consists of four faces, each calibrated to 12 fingers with markings every two fingers.

The object was acquired by J. A. Billmeir between 1955 and 1957 from Nicolas Landau, a Parisian collector and dealer. The accession number is 1957-84/173.

Evidence for this section
  • “The back contains 4 scales of the following types: Degree; Zodiacal signs; Calendar; Shadow square.”
  • “Billmeir bought it from Nicolas Landau, a collector and dealer of Paris, during the period 1955-57.”

Open research questions

  • What is the specific identity of the heraldic crouching lions on the throne?
  • Does the degree of wear on the star pointers indicate significant historical usage or later modification?

Source evidence

Recorded claims and source quotations for Astrolabe
FieldSource-reported valueSource quotation
MaterialBrass“Material Brass”
Dateca. 1300“Date ca. 1300”
Inventory Number45307“Inventory no. 45307”
Star Count25“The rete contains 25 stars.”
Throne TypeMoorish-arch“The throne is of the moorish arch type”
ProvenancePresented by J. A. Billmeir in 1957“Presented by J. A. Billmeir in 1957”
DealerNicolas Landau“Billmeir bought it from Nicolas Landau, a collector and dealer of Paris”

Visible details

  • Throne features crouching lions on either side of a fleur-de-lis
  • Rete includes bird-shaped star pointers
  • Shadow square occupies the lower-left and lower-right quadrants of the back

Research qualifications

  • Place of manufacture is uncertain and noted as 'Spain (?)' by the source
  • Provenance details suggest heraldic significance on the throne but the owner remains unidentified

Photograph identity and source facts were screened before import; rights clearance remains pending.

Consulted source

Astrolabe, inventory 45307 (Spain (?), ca. 1300)

Reviewed 2026-10-26 · Record b99ae20760

Terms in this record

Glossary explanations for terms named in this object’s record.

Other latin-inscribed astrolabe records