Torquetum

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The torquetum or turquet is a medieval astronomical instrument designed to take and convert measurements made in three sets of coordinates: Horizon, equatorial, and ecliptic. In a sense, the Torquetum is an analog computer. The first torqueta is thought to have been built by Jabir ibn Aflah (Geber) in the 12th century or 13th century, though the only surviving examples date from the 16th century. Detail from The Ambassadors. A torquetum can be seen in the famous portrait The Ambassadors (1533) by Hans Holbein the Younger. It is placed on the right side of the table, next to and above the elbow of the ambassador clad in a long brown coat or robe. The painting shows much of the details of the inscriptions on the disk and half disk, which make up the top of this particular kind of Torquetum.