Torquetum

The torquetum or turquet is a medieval astronomical instrument designed by persons unknown to take and convert measurements made in three sets of coordinates: horizon, equatorial, and ecliptic. It is characterised by R. P. Lorch as a combination of Ptolemy's astrolabon (Greek: aστpoλaẞov) and the plane astrolabe.^[1] In a sense, the torquetum is an analog computer.

^ Lorch, R. P. (1976). "The Astronomical Instruments of Jabir ibn Aflah and the Torquetum". Centaurus. 20 (1): 11–34. Bibcode:1976Cent...20...11L. doi:10.1111/j.1600-0498.1976.tb00214.x.

[:0-1] Lorch, R. P. (1976). "The Astronomical Instruments of Jabir ibn Aflah and the Torquetum". Centaurus. 20 (1): 11–34. Bibcode:1976Cent...20...11L. doi:10.1111/j.1600-0498.1976.tb00214.x.

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