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//Source(s): http://myhouse.com/mc/planet/astrodir/ASTROLAB.HTM (((kadrey remarks: This page was constructed and written by James E. Morrison, who teaches an Introduction to Astronomy course at Montgomery College at Tokoma Park in Connecticut.)))// "The Astrolabe in Europe "The astrolabe moved with Islam through North Africa into Spain (Andalusia) where it was introduced to European culture through Christian monasteries in northern Spain. "It is likely that information about the astrolabe was available in Europe as early as the 11th century, but European usage was not widespread until the 13th and 14th centuries. The earliest astrolabes used in Europe were imported from Moslem Spain with Latin words engraved alongside the original Arabic. It is likely that European use of Arabic star names was influenced by these imported astrolabes. "By the end of the 12th century there were at least a half dozen competent astrolabe treatises in Latin, and there were hundreds available only a century later. European makers extended the plate engravings to include astrological information and adapted the various timekeeping variations used in that era. Features related to Islamic ritual prayers were generally discarded in European instruments. "The astrolabe was widely used in Europe in the late Middle Ages and Renaissance, peaking in popularity in the 15th and 16th centuries, and was one of the basic astronomical education tools. A knowledge of astronomy was considered to be fundamental in education, and skill in the use of the astrolabe was a sign of proper breeding and education. Their primary use was, however, astrological. "Geoffrey Chaucer thought it was important for his son to understand how to use an astrolabe, and his 1391 treatise on the astrolabe demonstrates a high level of astronomical knowledge. "Astrolabe manufacturing was centered in Augsburg and Nuremberg in Germany in the fifteenth century, with some production in France. In the sixteenth century, the best instruments came from Louvain in Belgium. "By the middle of the seventeenth century astrolabes were made all over Europe. (...) A particularly interesting workshop was founded by Georg Hartmann in Nuremberg in about 1525. It is clear that Hartmann used an early form of mass production to produce his high quality instruments. It is very likely that most workshops acquired parts of finished instruments from specialists, or other shops were employed for services such as gilding. "Brass astrolabes were quite expensive, and only the wealthy could afford a good one. Paper astrolabes became available as printing developed, and many were surely made, although few survive. "Several interesting astrolabe variations to make a single instrument usable in all latitudes were invented in the 15th and 16th centuries, but due to their high cost and complex operation, never gained the popularity of the planispheric type. (...)" Richard Kadrey (kadrey@well.com)
 * Dead medium: the Astrolabe in Europe**
 * From: kadrey@well.com (Richard Kadrey)**