What were astrologers like, a thousand years ago? Or alchemists?
What’s your image of medieval, oriental wizards?
Workers at the Taqf ad Din Observatory, 1577. From Sahinhah-nama.
This summer the Museum of the Topkapi Palace in Istanbul, Turkey, hosted an exhibit entitled “Science and Technology in Islam.” The exhibit came from the Institute for the History of Arabic-Islamic Science at theUniversity of Johannes Wolfgang Goethe in Frankfurt, Germany. Middle Easterners who lived from the 11th to the 16th century were represented in the exhibit with about fifty different examples of their works. Some were original manuscripts, but most were copies of the scientists’ original instruments. The display cases held text books and retorts, astrolabes and water clocks and mills—much of the equipment
I’d expect a wizard to have used. But I didn’t see any crystal balls, or smell any bubbling witches’ brew. There were medical books with detailed anatomical drawings, and botanical texts illustrating the characteristics and uses of different flowers. Antique chemistry texts accompanied glass stills and retorts that looked as if they could be from a modern research facility.
I found a touch of humor in a miniature copy of a watermill: Not only was its purpose to raise stagnant water, but the machinery was operated by the lowliest of Middle Eastern working animals, the donkey.
Two kinds of instruments were represented with a number of examples. The first were gold and brass astrolabes (mainly for finding the altitudes of celestial objects). The principle of the astrolabe is still used in equatorial mounts for telescopes. One of the first in the display was a 16" flat gold astrolabe made in 1629 for the Safasid ruler Abbas II. Another gold astrolabe was from Toledo, Spain, made in 1029 during the time of the Moors. A similar 15th century instrument, called an equatory, could be used to calculate celestial longitudes and latitudes. Still another kind, this one called a torquetum, was made in the 12th century by Jabir b.Allah. It could measure the three astronomical coordinates, horizon, equatorial, and ecliptic, and could show their relationships.
The astrolabes were each a marvel of intricate and careful engraving. Not only were the network of circles and ellipses and the various tables finely drawn, but also the pieces were beautifully decorated with scrolls and arabesques and Arabic inscriptions. These were both precision instruments and prized possessions that a man would have used and displayed with pride.
One of the better known Middle Eastern scientists, al-Biruni, was represented in the museum by two inventions. The first was a gold, 8" spherical astrolabe; the other was a device for determining the specific gravity of solid objects. A Persian scholar, al-Biruni lived from 973 to 1048 AD. He was knowledgeable in physics, mathematics, astronomy, geography, and history; he taught Greek and Arabic science and philosophy, and conducted experiments on astronomical phenomena. He is quoted as having said, “Just because only Allah is omniscient, that doesn’t justify our ignorance.” Among others of his time, al-Biruni helped lay the foundations of scientific research.
The second well- represented instrument was the clepsydra or water clock, that measured the passage of time by the flow of water. Clepsydras commonly measured the amount of time a lawyer could talk in court in ancient Greece and Rome. One colorful clock in the shape of an elephant was from the early 13th century. An earlier one, from the 12th century, was a balance that indicated the passage of minutes. The most complicated clepsydra was made in the mid-13th century by another Middle Eastern scientist, Ridwan al-Sa’ati. It marked the full hours by opening a gate every hour -- balls dropped from the beaks of two birds into a sounding bowl. Quarter hours were marked by a pointer that moved horizontally. A semicircular disk on the top had 12 holes, lit from inside, to show the hours at night.
The 14th century astronomer, Ibn al-Shatir, was represented by a copy of his sundial from the Omayyad Mosque in Damascus. Al-Shatir was the scholar whose models of the Moon and the motions of Mercury predated similar models by Copernicus.
At the end of the exhibit, when I stopped to look back, what struck me was the quality of the work. Here were represented 600 years of complex and exacting workmanship and scholarship. The medieval, oriental wizards had crafted these things by hand, without the help of electricity, or controlled heat, or “clean rooms,” or computer technology. How often did their work explode in their faces? How often was it laughed out of court? And what do we owe to them now?
“Science and Technology in Islam,” at the Topkapi Museum, Istanbul, 21 June-15 August 2004. Paselk, Richard A.,“The Torquetum” http:// www.humboldt.edu/~rap1/EarlySciInstSite/Instruments/Torquetum/Turq.html
Saliba,George “Greek Astronomy and the Medieval Arabic Traditions,”American Scientist, July-August 2002. http://www.midtownreview.com