Accession No

1467

Brief Description

astrolabe, Flemish-style, with latitude plates and universal projection, attributed to School of Arsenius, tentatively attributed to Zeelst, Flemish or Dutch, c. 1570

Origin

Flanders [modern-day Belgium]; or a Dutch (Holland) copy of a Flemish instrument

Maker

School of Arsenius [attributed] Zeelst [tentative attribution]

Class

astronomy

Earliest Date

1570

Latest Date

1580

Inscription Date

Material

metal (brass)

Dimensions

diameter 285 mm

Special Collection

Provenance

On loan from King's College, University of Cambridge from 18/07/1968.

Inscription

Description Notes

Astrolabe, Flemish-style, with latitude plates and universal projection, School of Arsenius, c. 1570.

Planispheric astrolabe of brass, with rete, four plates, pin, rule, and horse.

Mater with decorative throne welded to brass arc riveted to rim. Suspension ring loosely held to throne by ring. Rim of mater is marked with scales of time (twice XII hours) and degrees (labelled in tens of degrees), divided to half degrees/two minutes. Degree scale is labelled anti-clockwise from VI, i.e. East. Engraved in the womb is a Quadratum Nauticum: a square divided to 2 degree units and labelled in tens along its edges, 90-0-90. Outside, the edges are labelled: Latitudo mino vel Austr, Latitudo maior aut borealior, Longitudo minor sive occidet, and Longitudo maior seu orient. Within square, marked by grid and lines radiating from centre, are labelled directions and wind names in Dutch: Norden Septentrio, Nordt ten osten, Nordt nordt oest, Nordt oesten nordt, Nordt oesten, Nordt oesten oest, Oest nordt oest, Oest ten norden, Oest oriens, Oost ten Zuyden, Oest Zuyd oest, Zuyd oesten oest, Zuyd oest, Zuyd oesten zuyd, Zuÿd zuÿd oest, Zuyd ten oesten, Zuÿd Meridies, Zuyd ten westen, West zuyd uuest, Zuÿd uuest ten zuÿd, Zuÿd westen, Zuyd west ten uuesten, West zuÿd west, west ten Zuyden, West Occidens, West ten norden, West nordt uuest, Nordt uuesten west, Nordt westen, Nordt uuesten nordt, Nordt nordt west, Nordt ten westen; and Apartias, Aquilo, GRECHO, Cecias, Subsolanus, Wlturnus, SYROCHO, Euroaster, Auster, Lybonoch~, LEBECCIO, Africus, Zephrus, Corus, MAGISTRALIS, Circius.
On the reverse is a universal projection of the Frisius type, with 10 labelled stars: aquila, Arct’rus, Hircus, Liera [Lyra?], Oculis 2, Canis minor, Orionis sinister pes, Canis maior, postrema fu aque, Canopus.

Flemish-style rete with tulip within the ecliptic, and overlapping knotwork effect. Ecliptic divided to single degrees, and marked in tens. Zodiac houses marked with astrological signs, house names (in Latin), and numbers 1 (Aries)-12. Thirty-one star pointers, labelled: Hircus, dorsu~ 4, Principiu~ Caude urse ma:, bootis sinister hum~:, Arcturus, Corona Septen~:, Caput Hercules, Caput drconis, Ophiuci caput, Aquila, Pegasi humerus, Liera [=lyra?], crus pegasi, pegasi umbilicus, pectus cascio (within ecliptic); cauda capricorni, crus aquaru~, cauda ceti, venter ceti, Ceti itares (?), Oculus 2, Orionis sinister pes, Orionis sinister humerus,Canis maior, Canis minor, Cor leonis, Lucida Hydre, Cariens fundus, Corniola dextra, Spica virginis,Cor 8 (outside ecliptic). Pointer for Cor leonis, originally attached to ecliptic, has broken into two. Some construction lines visible on reverse.

Latitude plates for 39o & 49o; 45o & 52o30’; 48 o & 51o. Fourth plate engraved with calendar zodiacal scales, shadow square, and lines of equal hours. First point of Aries is 11th of March. On reverse is a Horizontale catholicu~, with horizons marked at 2 degree intervals.

References

Events

Description
An astrolabe is a model of the heavens with the earth placed at the centre. A section of the heavens is projected on to the astrolabe. The co-ordinates of stars and planets are depicted on a grid called the rete. The earth is represented by latitude plates of which there are more than one. This is because the movement of the stars depends upon the latitude of the place from where the observation is made. Cambridge has a latitude of 52°, Rome 42°, Madrid 41°, and Paris 49°. Each latitude plate has circles and lines engraved on them which include the tropic of Cancer and Capricorn, the equator and a twilight line. The rete and latitude plates are housed within the mather which has a raised edge called the limb. On European astrolabes the limb is engraved with a degree scale showing 0° to 360° and / or a scale of 24 equal hours.

On the back of the astrolabe are engraved several scales including a calendar scale and a shadow square. On Islamic astrolabes extra scales and tables are engraved for finding the direction of Mecca (for times of prayer). At the back of the astrolabe is also the alidade (see diagram above). The alidade has sights through which an astronomer would take simple observations of the sun or of a particular star, to find the time of day or night. The sights can also be used for finding the heights of buildings, trees or hills.

From display label:

A standard astrolabe possessing engraved plates for 6 latitudes, with a Frisius universal projection on the reverse. The tulip shape in the rete is a characteristic feature of Flemish astrolabe design, although, with the migration of craftsmen, it also came to be employed outside the Low Countries. A wind rose inscribed in the womb is labelled in Latin and Dutch.

FM:39709