Abu Al Fath Al Khazini was a 12th century astronomer, engineer, and physicist from Iraq. He made significant contributions to mechanics, physics, and hydrostatics through his book Meezan Al-Hikmah. Some of his achievements included determining the direction of prayer for many Muslim states, developing theories on gravity, hydrostatics, and the speed at which objects fall. He is considered a pioneering authority in physics who made advances beyond his influential teachers, including Ibn Sina, Al-Beiruni, and Ibn al-Haytham.

1. Abu Al Fath Al Khazini (12th century ) ‫الخازني‬ ‫الفاتح‬ ‫أبو‬
He is Abu Al-Fath `Abd al-Rahamn Al-Khazin, or Al-Khazini:
a man of wisdom, an astronomer and an engineer.
He evoked the admiration and astonishment of many when he came out with
his book, Meezan Al-Hikmah, which was a marvel in the fields of mechanics,
physics and hydrostatics.
He was also interested in astronomy and he determined the direction of
the Qiblah in most Muslim states.

2. Al-Khazini stands as an authority in physics for all ages.
He based his determination of the Qiblah on his readings from Ibn al-Haytham
and Al-Beiruni. Most historians of science are unanimous that Al-Khazini stands
as an authority in physics for all generations, that he even surpassed his
teachers
Ibn Sina (Avicenna), Al-Beiruni and Ibn al-Haytham
(who was the first to attempt the discovery of the speed of light) –
all of whom had discussed gravity, albeit not very scientifically and accurately.
He outstripped them, in general, in this discipline as well, and particularly in
Dynamics and Hydrostatics.
His own theories in these two fields are taught to this day.
In astronomy, he excelled in making tables known as the Sinjari tables.
He spoke during his studies about the resistance which bodies immersed in
liquids generally encounter.

3. Abu Al Fath Al Khazini (12th century ) ‫الخازني‬ ‫الفاتح‬ ‫أبو‬
He arrived at a formula that determines the abstract weight of masses
composed of two different materials.
He preceded Torshilly in referring to air as matter with mass, and stating that
air has mass and capillary action similar to liquids.
He also stated that weights of immersed masses are less than their real
weights.
He also explained that the Archimedes’ principle applies to gases in addition to
liquids; such revelations paved the way for the invention of the barometer, air-
vacuums, and pumps.
He also wrote on theories of light, and calculated the deflection of light upon its
passage through air.

4. Abu Al Fath Al Khazini (12th century ) ‫الخازني‬ ‫الفاتح‬ ‫أبو‬
He preceded Newton by several centuries, though not acknowledged by the
West.
He made great efforts in his work on specific weights and gravity and
demonstrated experimentally how all parts of the body direct their descent
towards the centre of the earth due to gravity; showing that the variation in
gravitational pull on different segments of the descending body result from the
variation in the distance between the respective segments and the centre of the
earth.
He based his inferences on experiments and scientific calculations.

5. Abu Al Fath Al Khazini (12th century ) ‫الخازني‬ ‫الفاتح‬ ‫أبو‬
He authored many books including the Mizan Al-Hikmah which came in eight
volumes.
It spoke about hydrostatics, weights, theories on gravity, Archimedes’ and
Menelaus’s views on hydrostatics, specific weights of different materials, and
astronomy.
It solved problems, stated exercises and listed the specific weights of different
materials in tabulated form.
Al-Khazini discussed the relation between the speed at which a body falls to the
distance and time it takes; he gave that in a formula for discovering which
scientists in the West – like Galileo, Newton, and others – claimed credit several
centuries later.

6. Abu Al Fath Al Khazini (12th century ) ‫الخازني‬ ‫الفاتح‬ ‫أبو‬
He completed his Mizan al-Hikmah in 515H/1121CE.
It is the most fundamental work on the hydrostatic balance and its varieties.
This instrument in itself is a crowning achievement throughout the long process
of earlier methods and models suggested and produced over centuries.
The book is also remarkable and unique on mechanics, hydrostatics and
physics.
It contains the tables of specific gravities of many solids and liquids and also the
history of the subject.
The book published in Hyderabad Deccan (1359H/1940CE) contains 8
discourses divided into Abwab (chapters) and fusul (sections).

7. He describes the balance he invented, shows indebtedness to al-Bayruni,
elaborates upon some of the important earlier concepts, discusses the theorems
derived from the classical works of Archimedes and Euclid, and describes the
aerometer of Pappus.
The book also contains information about air, its weight and elevating power like
that of the liquids. He also shows that Archimedes’ principle is true to liquids as
well as gases.
Khazini discusses and explains the gravity of air, capillarity, use of aerometer to
measure densities and temperature of liquids, theory of the lever.
Khazini’s hydrostatic balance was the most perfect of the balances so far
developed.
He defined weight as “the force inherent in solid bodies which cause them to
move, of their own accord, in a straight line towards the centre of the earth; and
towards this centre alone this force, in turn depends upon the density of the
body.” He knew that temperature influences density.