Astrolabe Catalogue

astrolabe, inventory number 42223 from London, 1559
thumbnail for astrolabe (front), inventory number 42223 from London, 1559
thumbnail for astrolabe (back), inventory number 42223 from London, 1559
thumbnail for astrolabe (rete front), inventory number 42223 from London, 1559
MakerThomas Gemini
Inventory no.42223
AcquisitionTransferred from the University Observatory, Oxford, in 1936

This astrolabe was made for Queen Elizabeth I. Made by the immigrant craftsman Thomas Gemini in the year of her coronation, it carries her coat-of-arms and the inscription 'Elizabeth Dei Gratia Angliæ Franciæ & Hiberniæ Regina etc.' It is possible - indeed likely - that it was commissioned by her court favourite Robert Dudley, the future Earl of Leicester. Dudley's household accounts for 1559 record a payment to Gemini for an unspecified but evidently substantial astronomical instrument.

From later inscriptions we know that the instrument was owned by John Greaves, Savilian Professor of Astronomy in Oxford, and was used by him in a journey to the Levant in 1637-40. It was presented to the University for the use of the Savilian Professors, by John's brother Nicholas Greaves.

View all images for this astrolabe
View detailed provenance for this astrolabe

Throne, Ring and Shackle

The throne is of the simple type made of brass with s-shaped scroll work support(s) made of brass attached with integrated base made of brass . More information


The mater and limb are of three pieces construction. Scales on the limb: equal hours scale; degree scale. More information


The back contains 1 scales of the following types: Degree. The universal on the back contains 2 scales. More information

Rete, Nut & Bolt

The rete contains 28 stars. The zodiac on the rete is labelled: Aries , Taurus , Gemini , [only the symbol is present] , Leo , Virgo , Libra , Scorpius , Sagittarius , Capricornus , Aquarius , Pisces.

The rete contains 1 scale of the following type: Ecliptic.
The rete is attached using a nut & bolt. Brass screw with washer thread into the arm on the back. More information


There is one plate . More information

Rules & Alidades

Type Details
AlidadeDouble-ended, counter-changed.
AlidadeSingle-ended. Rule for use with the universal planisphere. Slotted for a cursor and bracchiolus, which are missing.
More information


MHS Home | Contact Us | ©2006 Museum of the History of Science