This brass astrolabe unusually does not have a mater, but consists of a plate with a zodiacal calendar scale as well as markings for a plate for the sixth climate on one side, and a degree scale, a double horary quadrant and a shadow square on the other side. A simple throne is an integral part of the body.
The OBVERSE of the body has two circular scales along the edge as follows (from the outside: a) A zodiacal scale with the usual Latin names of the signs in Latin (some abbreviated, e.g., 'Chapri' for Capricorn), each sign with a 30 degree scale, numbered by 5 and divided to 1; b) A calendrical scale with the usual Latin names of the months (some abbreviated, March spelled 'MARCIVS' and October as 'OCTV') and the corresponding number of days, numbered by 5 and divided to 1. The equinoxes are at the 10th March and 13 1/2 September.
The centre of the disc has markings for a plate for the sixth climate, marked 'C 6'. The almucantars are marked for every 5 degrees, numbered by 5 from 5 to 75. There are hour curves for equal hours 1 to 24. The horizon is marked 'ORIZON', and east and west are marked 'ASENDENS' and 'DESENDENS'.
The REVERSE has a double degree scale: the outer scale clockwise 0 to 360 and the inner scale four times 0 to 90.
The top half of the disc is marked as a double HORARY QUADRANT, each numbered 1 to 6 to 12. The lower half is engraved with a double SHADOW SCALE to the base 12, numbered by 1. The date and the signature are given in the centre of the scale.
The RETE is damaged and part of the tropic of Capricorn is missing. The ecliptic is marked with the first letters of the zodiacal signs, each sign has a 30 degree scale, numbered by 10 and divided to 5 and 1. The unlabelled star pointers are wedge shaped.
- Made in: Italy
- Diameter: 115 millimetres
Inscription Positionback, in centre of double shadow scale
Inscription Content1507 OPVS FALCONI
Inscription Commentdate of production and name of maker
This very unusual instrument has the markings for the mater, plates and back all in one body. The equal hour scale is very unusually indicated by 24 curves.
The instrument was in the 'wartime exhibition' at the British Museum in the gallery destroyed by incendiary bombs in 1941 and the rete is consequently badly damaged.For instruments by Falcono, see Gerard L'E. Turner, "Two Early Renaissance Astrolabes by Falcono of Bergamo", in Marco Beretta, Paolo Galluzzi and Carlo Triarico (eds), Musa Musaei. Studies on Scientific Instruments and Collections in Honour of Mara Miniati (Florence, 2003), pp. 53-62.
Britain, Europe and Prehistory
Astrolabe; sheet brass, without rim; a) outer edge: zodiac signs and degrees; scale of months and days; equinoxes at 10 March and 13.5 September; rete with 21 crude star-pointers(renewals); b) outer scale of degrees; two shadow squares; signature; scale of curved lines of unequal hours.
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Object reference number: MCC3710
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