Astrolabe Catalogue

astrolabe, inventory number 47674 from Paris, ca. 1400
thumbnail for astrolabe (front), inventory number 47674 from Paris, ca. 1400
thumbnail for astrolabe (back), inventory number 47674 from Paris, ca. 1400
thumbnail for astrolabe (rete front), inventory number 47674 from Paris, ca. 1400
Dateca. 1400
MakerJean Fusoris
Inventory no.47674
AcquisitionPresented by Lewis Evans in 1924

Several regional origins were formerly suggested for this beautiful late medieval astrolabe. Lewis Evans, in whose collection it came to the Museum in 1924, thought it was Spanish. R. T. Gunther, the Museum’s first Curator and author of The Astrolabes of the World (1932), listed it as Spanish but thought it was French. What confused them was that the latitude plate engraved within the mater is marked 40, but on examination the almucantars are for approximately 49° (Paris). Gunther suggested that the figure 40 was the co-latitude (the difference between the latitude and 90), but that sounds too clever an explanation. Perhaps it was just a mistake.

The other difficulty was that in Evans and Gunther’s time the family of European late Gothic astrolabes to which this instrument belongs was only just beginning to be recognized as a distinctive group. It was not until a detailed study was published by Emmanuel Poulle in 1963 that they could be attributed to the Paris workshop of Jean Fusoris (in operation from the 1390s to 1415). This instrument can now be recognized as typical of the Fusoris atelier, with one difference, which is that many of the stars on the rete are marked with their Arabic rather than their Latin names.

It is possible that the figure 40 was placed on the plate by an early owner, as it differs slightly from the shape of the numerals around the limb. Near to it, but peculiarly off-centre, is the inscription ‘Jeh Charla’, or perhaps ‘Jeh Char la’. A horizontal bar through the first h, symbol for contraction in medieval handwriting, indicates that it should be read as Jehan, the contemporary spelling of the French name Jean. This early owner – if that is what he is – was thus a Frenchman named Jean Charla or, if the inscription is unfinished, perhaps Jean Charles la [something]. Or, more intriguingly, it could be a phonetic rendering of the name of Fusoris’s business partner, Jean de Châlon, who died in 1414.

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Throne, Ring and Shackle

The throne is of the three-lobed type made of brass with integrated support(s) made of brass and has a simple, round cross-section ring made of brass and eye-bolt type shackle made of brass . More information


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


The back contains 5 scales of the following types: Zodiacal signs; Calendar; Equal hours; Shadow square. More information

Rete, Pin & Wedge

The rete contains 38 stars. The zodiac on the rete is labelled: aries , taurus , geminy , cancher , Leo , virgo , Libra , scorpius , sagetarius , kapricornus , akarius , pi .
The rete is attached using a pin & wedge. simply decorated. More information

Rules & Alidades

Type Details
RuleDouble-ended, counter-changed. The rule is not original. Possible replacement?.
AlidadeDouble-ended, counter-changed. Center contains the dominical letters “A-G” for determining actual dominical letter (with calendar scale).
More information


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