Abū al-'Iz Ibn Ismā'īl ibn al-Razāz al-Jazarī (1136 – 1206)
Al Jazari was a prominent Arab polymath: a scholar, inventor, mechanical engineer, craftsman, artist and astronomer from Al-Jazira, Mesopotamia who lived during the Islamic Golden Age (Middle Ages).
He is best known for writing the Kitáb fí ma'rifat al-hiyal al-handasiyya (Book of Knowledge of Ingenious Mechanical Devices) in 1206, where he described fifty mechanical devices along with instructions on how to construct them.
Biography:
Little is known about Al-Jazari, and most of that comes from the introduction to his Book of Knowledge of Ingenious Mechanical Devices.
He was named after the area in which he was born, al-Jazira—the traditional Arabic name for what was northern Mesopotamia and what is now northern Iraq and northeastern Syria, between the Tigris and the Euphrates.
Like his father before him, he served as chief engineer at the Artuklu Palace, the residence of the Diyarbakır branch of the Turkish Artuqid dynasty which ruled across eastern Anatolia as vassals of the Zangid rulers of Mosul and later Ayyubid general Saladin.
Al-Jazari was part of a tradition of craftsmen and was thus more of a practical engineer than an inventor who appears to have been "more interested in the craftsmanship necessary to construct the devices than in the technology which lay behind them" and his machines were usually "assembled by trial and error rather than by theoretical calculation."
Some of his devices were also inspired by earlier devices, such as one of his monumental water clocks being based on that of a Pseudo-Archimedes.
Mechanisms and methods:
While many of al-Jazari's inventions may now appear to be trivial, the most significant aspect of al-Jazari's machines are the mechanisms, components, ideas, methods and design features which they employ.
Crankshaft and connecting rod mechanismWhile many of al-Jazari's inventions may now appear to be trivial, the most significant aspect of al-Jazari's machines are the mechanisms, components, ideas, methods and design features which they employ.
Crankshaft and connecting rod mechanism
The hand-operated crank was known in Han China, but Al-Jazari was the first to incorporate it in a machine and he thus invented the crankshaft. It transforms continuous rotary motion into a linear reciprocating motion, and is central to modern machinery such as the steam engine, internal combustion engine and automatic controls.The hand-operated crank was known in Han China, but Al-Jazari was the first to incorporate it in a machine and he thus invented the crankshaft. It transforms continuous rotary motion into a linear reciprocating motion, and is central to modern machinery such as the steam engine, internal combustion engine and automatic controls.
The connecting rod was also invented by al-Jazari, and was used in a crank and connecting rod system in a rotating machine he developed in 1206, in two of his water-raising machines: the crank-driven saqiya chain pump and the double-action reciprocating piston suction pump.
Design and construction methods
Donald Routledge Hill writes:
"We see for the first time in al-Jazari's work several concepts important for both design and construction: the lamination of timber to minimize warping, the static balancing of wheels, the use of wooden templates (a kind of pattern), the use of paper models to establish designs, the calibration of orifices, the grinding of the seats and plugs of valves together with emery powder to obtain a watertight fit, and the casting of metals in closed mold boxes with sand."
Escapement mechanism in a rotating wheel
Al-Jazari invented a method for controlling the speed of rotation of a wheel using an escapement mechanism.
Mechanical controls
According to Donald Routledge Hill, al-Jazari described several early mechanical controls, including "a large metal door, a combination lock and a lock with four bolts."
Segmental gearAccording to Donald Routledge Hill, al-Jazari described several early mechanical controls, including "a large metal door, a combination lock and a lock with four bolts."
Segmental gear
A segmental gear is "a piece for receiving or communicating reciprocating motion from or to a cogwheel, consisting of a sector of a circular gear, or ring, having cogs on the periphery, or face."
Professor Lynn Townsend White, Jr. wrote:
"Segmental gears first clearly appear in Al-Jazari, in the West they emerge in Giovanni de Dondi‘s astronomical clock finished in 1364, and only with the great Sienese engineer Francesco di Giorgio (1501) did they enter the general vocabulary of European machine design."
Water-raising machines
Al-Jazari invented five machines for raising water, as well as watermills and water wheels with cams on their axle used to operate automata, in the 12th and 13th centuries, and described them in 1206. It was in these water-raising machines that he introduced his most important ideas and components.
Saqiya chain pumpsAl-Jazari invented five machines for raising water, as well as watermills and water wheels with cams on their axle used to operate automata, in the 12th and 13th centuries, and described them in 1206. It was in these water-raising machines that he introduced his most important ideas and components.
Saqiya chain pumps
The first known use of a crankshaft in a chain pump was in one of al-Jazari's saqiya machines. The concept of minimizing intermittent working is also first implied in one of al-Jazari's saqiya chain pumps, which was for the purpose of maximising the efficiency of the saqiya chain pump The first known use of a crankshaft in a chain pump was in one of al-Jazari's saqiya machines. The concept of minimizing intermittent working is also first implied in one of al-Jazari's saqiya chain pumps, which was for the purpose of maximising the efficiency of the saqiya chain pump
Al-Jazari also constructed a water-raising saqiya chain pump which was run by hydropower rather than manual labour, though the Chinese were also using hydropower for chain pumps prior to him.
Saqiya machines like the ones he described have been supplying water in Damascus since the 13th century up until modern times, and were in everyday use throughout the medieval Islamic world.
Double-action suction pump with valves and reciprocating piston motion
In 1206, Al-Jazari described the first suction pipes, suction pump, double-action pump, valve, and crank-connecting rod mechanism, when he invented a twin-cylinder reciprocating piston suction pump.
This pump is driven by a water wheel, which drives, through a system of gears, an oscillating slot-rod to which the rods of two pistons are attached.
The pistons work in horizontally opposed cylinders, each provided with valve-operated suction and delivery pipes.
The delivery pipes are joined above the centre of the machine to form a single outlet into the irrigation system. This may be the only one of al-Jazari's water-raising machines which had a direct significance for the development of modern engineering.
This pump is remarkable for three reasons:
Al Jazari was a prominent Arab polymath: a scholar, inventor, mechanical engineer, craftsman, artist and astronomer from Al-Jazira, Mesopotamia who lived during the Islamic Golden Age (Middle Ages).
He is best known for writing the Kitáb fí ma'rifat al-hiyal al-handasiyya (Book of Knowledge of Ingenious Mechanical Devices) in 1206, where he described fifty mechanical devices along with instructions on how to construct them.
Biography:
Little is known about Al-Jazari, and most of that comes from the introduction to his Book of Knowledge of Ingenious Mechanical Devices.
He was named after the area in which he was born, al-Jazira—the traditional Arabic name for what was northern Mesopotamia and what is now northern Iraq and northeastern Syria, between the Tigris and the Euphrates.
Like his father before him, he served as chief engineer at the Artuklu Palace, the residence of the Diyarbakır branch of the Turkish Artuqid dynasty which ruled across eastern Anatolia as vassals of the Zangid rulers of Mosul and later Ayyubid general Saladin.
Al-Jazari was part of a tradition of craftsmen and was thus more of a practical engineer than an inventor who appears to have been "more interested in the craftsmanship necessary to construct the devices than in the technology which lay behind them" and his machines were usually "assembled by trial and error rather than by theoretical calculation."
Some of his devices were also inspired by earlier devices, such as one of his monumental water clocks being based on that of a Pseudo-Archimedes.
Mechanisms and methods:
While many of al-Jazari's inventions may now appear to be trivial, the most significant aspect of al-Jazari's machines are the mechanisms, components, ideas, methods and design features which they employ.
Crankshaft and connecting rod mechanismWhile many of al-Jazari's inventions may now appear to be trivial, the most significant aspect of al-Jazari's machines are the mechanisms, components, ideas, methods and design features which they employ.
Crankshaft and connecting rod mechanism
The hand-operated crank was known in Han China, but Al-Jazari was the first to incorporate it in a machine and he thus invented the crankshaft. It transforms continuous rotary motion into a linear reciprocating motion, and is central to modern machinery such as the steam engine, internal combustion engine and automatic controls.The hand-operated crank was known in Han China, but Al-Jazari was the first to incorporate it in a machine and he thus invented the crankshaft. It transforms continuous rotary motion into a linear reciprocating motion, and is central to modern machinery such as the steam engine, internal combustion engine and automatic controls.
The connecting rod was also invented by al-Jazari, and was used in a crank and connecting rod system in a rotating machine he developed in 1206, in two of his water-raising machines: the crank-driven saqiya chain pump and the double-action reciprocating piston suction pump.
Design and construction methods
Donald Routledge Hill writes:
"We see for the first time in al-Jazari's work several concepts important for both design and construction: the lamination of timber to minimize warping, the static balancing of wheels, the use of wooden templates (a kind of pattern), the use of paper models to establish designs, the calibration of orifices, the grinding of the seats and plugs of valves together with emery powder to obtain a watertight fit, and the casting of metals in closed mold boxes with sand."
Escapement mechanism in a rotating wheel
Al-Jazari invented a method for controlling the speed of rotation of a wheel using an escapement mechanism.
Mechanical controls
According to Donald Routledge Hill, al-Jazari described several early mechanical controls, including "a large metal door, a combination lock and a lock with four bolts."
Segmental gearAccording to Donald Routledge Hill, al-Jazari described several early mechanical controls, including "a large metal door, a combination lock and a lock with four bolts."
Segmental gear
A segmental gear is "a piece for receiving or communicating reciprocating motion from or to a cogwheel, consisting of a sector of a circular gear, or ring, having cogs on the periphery, or face."
Professor Lynn Townsend White, Jr. wrote:
"Segmental gears first clearly appear in Al-Jazari, in the West they emerge in Giovanni de Dondi‘s astronomical clock finished in 1364, and only with the great Sienese engineer Francesco di Giorgio (1501) did they enter the general vocabulary of European machine design."
Water-raising machines
Al-Jazari invented five machines for raising water, as well as watermills and water wheels with cams on their axle used to operate automata, in the 12th and 13th centuries, and described them in 1206. It was in these water-raising machines that he introduced his most important ideas and components.
Saqiya chain pumpsAl-Jazari invented five machines for raising water, as well as watermills and water wheels with cams on their axle used to operate automata, in the 12th and 13th centuries, and described them in 1206. It was in these water-raising machines that he introduced his most important ideas and components.
Saqiya chain pumps
The first known use of a crankshaft in a chain pump was in one of al-Jazari's saqiya machines. The concept of minimizing intermittent working is also first implied in one of al-Jazari's saqiya chain pumps, which was for the purpose of maximising the efficiency of the saqiya chain pump The first known use of a crankshaft in a chain pump was in one of al-Jazari's saqiya machines. The concept of minimizing intermittent working is also first implied in one of al-Jazari's saqiya chain pumps, which was for the purpose of maximising the efficiency of the saqiya chain pump
Al-Jazari also constructed a water-raising saqiya chain pump which was run by hydropower rather than manual labour, though the Chinese were also using hydropower for chain pumps prior to him.
Saqiya machines like the ones he described have been supplying water in Damascus since the 13th century up until modern times, and were in everyday use throughout the medieval Islamic world.
Double-action suction pump with valves and reciprocating piston motion
In 1206, Al-Jazari described the first suction pipes, suction pump, double-action pump, valve, and crank-connecting rod mechanism, when he invented a twin-cylinder reciprocating piston suction pump.
This pump is driven by a water wheel, which drives, through a system of gears, an oscillating slot-rod to which the rods of two pistons are attached.
The pistons work in horizontally opposed cylinders, each provided with valve-operated suction and delivery pipes.
The delivery pipes are joined above the centre of the machine to form a single outlet into the irrigation system. This may be the only one of al-Jazari's water-raising machines which had a direct significance for the development of modern engineering.
This pump is remarkable for three reasons:
The first known use of a true suction pipe (which sucks fluids into a partial vacuum) in a pump.
The first application of the double-acting principle.
The conversion of rotary to reciprocating motion, via the crank-connecting rod mechanism.
Al-Jazari's suction piston pump could lift 13.6 metres of water, with the help of delivery pipes. This was more advanced than the suction pumps that appeared in 15th-century Europe, which lacked delivery pipes. It was not, however, any more efficient than a noria commonly used by the Muslim world at the time. This pump is also notable for incorporating the only known copy of the Byzantine siphon (used for pumping Greek fire).
Water supply system
Al-Jazari developed the earliest water supply system to be driven by gears and hydropower, which was built in 13th century Damascus to supply water to its mosques and Bimaristan hospitals. The system had water from a lake turn a scoop-wheel and a system of gears which transported jars of water up to a water channel that led to mosques and hospitals in the city.
Automata
Al-Jazari built automated moving peacocks driven by hydropower. He also invented the earliest known automatic gates, which were driven by hydropower. He also created automatic doors as part of one of his elaborate water clocks.
Al-Jazari also designed and constructed a number of other automata, including automatic machines, home appliances, and musical automata powered by water. Al-Jazari also invented water wheels with cams on their axle used to operate automata.
Mark E. Rosheim summarizes the advances in robotics made by Arab engineers, especially Al-Jazari, as follows:
"Unlike the Greek designs, these Arab examples reveal an interest, not only in dramatic illusion, but in manipulating the environment for human comfort. Thus, the greatest contribution the Arabs made, besides preserving, disseminating and building on the work of the Greeks, was the concept of practical application. This was the key element that was missing in Greek robotic science."
"The Arabs, on the other hand, displayed an interest in creating human-like machines for practical purposes but lacked, like other preindustrial societies, any real impetus to pursue their robotic science."
Drink-serving waitress
One of Al-Jazari's humanoid automata was a waitress that could serve water, tea or drinks. The drink was stored in a tank with a m where the drink drips into a bucket and, after seven minutes, into a cup, after which the waitress appears out of an automatic door serving the drink.
Hand-washing automaton with flush mechanism
Al-Jazari invented a hand washing automaton incorporating a flush mechanism now used in modern flush toilets. It features a female humanoid automaton standing by a basin filled with water. When the user pulls the lever, the water drains and the female automaton refills the basin.
Peacock fountain with automated servants
Al-Jazari's "peacock fountain" was a more sophisticated hand washing device featuring humanoid automata as servants which offer soap and towels. Mark E. Rosheim describes it as follows:
"Pulling a plug on the peacock's tail releases water out of the beak; as the dirty water from the basin fills the hollow base a float rises and actuates a linkage which makes a servant figure appear from behind a door under the peacock and offer soap. When more water is used, a second float at a higher level trips and causes the appearance of a second servant figure — with a towel!"
Candle clocks
"The candle, whose rate of burning was known, bore against the underside of the cap, and its wick passed through the hole. Wax collected in the indentation and could be removed periodically so that it did not interfere with steady burning. The bottom of the candle rested in a shallow dish that had a ring on its side connected through pulleys to a counterweight. As the candle burned away, the weight pushed it upward at a constant speed. The automata were operated from the dish at the bottom of the candle. No other candle clocks of this sophistication are known."
Al-Jazari's candle clock also included a dial to display the time and, for the first time, employed a bayonet fitting, a fastening mechanism still used in modern times.
Elephant clock
Elephant clock
Programmable castle clock
It was a complex device that was about 11 feet (3.4 m) high, and had multiple functions besides timekeeping. It included a display of the zodiac and the solar and lunar orbits, and an innovative feature of the device was a pointer in the shape of the crescent moon which travelled across the top of a gateway, moved by a hidden cart, and caused automatic doors to open, each revealing a mannequin, every hour.
Another innovative feature was the ability to re-program the length of day and night everyday in order to account for the changing lengths of day and night throughout the year.
Yet another innovative feature of the device was five robotic musicians who automatically play music when moved by levers operated by a hidden camshaft attached to a water wheel.
Other components of the castle clock included a main reservoir with a float, a float chamber and flow regulator, plate and valve trough, two pulleys, crescent disc displaying the zodiac, and two falcon automata dropping balls into vases.
Weight-driven water clocks
Weight-driven water clocks
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