Al-Khazini
الخازني
The Master of the Science of Weights
Born: ~1115 CE, Merv (modern Turkmenistan)
Died: ~1130 CE, Merv
Also known as: Abu al-Fath Abd al-Rahman al-Khazini, Abd al-Rahman al-Khazini
Al-Khazini was a physicist and astronomer whose "Book of the Balance of Wisdom" was the most sophisticated medieval work on statics, hydrostatics, and the determination of specific gravities. His precise measurements of the densities of metals and gemstones remained unsurpassed for centuries.
Key Accomplishments
- Authored "The Book of the Balance of Wisdom," the most advanced medieval work on hydrostatics and specific gravities
- Measured the densities of metals and gemstones with accuracy within 1% of modern values
- Developed precision hydrostatic balances for detecting counterfeit coins and assessing metal purity
- Compiled the "Zij al-Sanjari," important astronomical tables for the Seljuq court
The Full Story
Abu al-Fath Abd al-Rahman al-Khazini was a scholar of Byzantine Greek origin who was enslaved as a boy and brought to Merv, in the Seljuq Empire (modern Turkmenistan). His owner, a treasury official named al-Khazin, recognized his intellectual gifts and provided him with an excellent education in mathematics and the sciences. Al-Khazini chose to remain in scholarly life even after gaining his freedom.
His masterwork, "Kitab Mizan al-Hikma" (The Book of the Balance of Wisdom), completed in 1121 CE, is one of the most remarkable scientific treatises of the medieval period. It is a comprehensive work on mechanics, hydrostatics, and the science of balances. Al-Khazini described the construction and use of precision hydrostatic balances for determining the specific gravities of metals, gemstones, and alloys. His measured values for the densities of various substances were remarkably accurate, in some cases differing from modern values by less than 1%.
The "Book of the Balance of Wisdom" also contained discussions on the nature of gravity, the concept of a center of gravity, and the physics of levers and balances. Al-Khazini recognized that the weight of a body varies depending on the density of the medium in which it is immersed, anticipating Archimedes' principle in sophisticated practical applications. He used these principles for purposes including detecting counterfeit coins and assessing the purity of metals.
Al-Khazini also compiled the "Zij al-Mu'tabar al-Sanjari" (The Verified Astronomical Tables Dedicated to the Seljuq Sultan Sanjar), an important set of astronomical tables. His work on specific gravity and hydrostatics had no equal in the medieval world and influenced later scholars in both the Islamic world and Europe.
Places
Connected Figures
Al-Biruni
The Master of Geodesy
Earlier scientist whose specific gravity measurements he built upon and refined
The Golden AgeOmar Khayyam
The Mathematician-Poet of Nishapur
Near-contemporary mathematician and astronomer in the Seljuq world
The Seljuk WorldNizam al-Mulk
Founder of the Nizamiyya Universities
Earlier Seljuq vizier whose patronage of learning created the milieu he worked in
Notes
Sources
- [1]N. Khanikoff, "Analysis and Extracts of the Book of the Balance of Wisdom," Journal of the American Oriental Society, 1860
- [2]Donald R. Hill, "Islamic Science and Engineering" (Edinburgh University Press, 1993)
- [3]Eilhard Wiedemann, "Uber al-Khazini," in Sitzungsberichte der Physikalisch-Medizinischen Sozietat, Erlangen, 1906