1. Water-raising Machines
- · Shaduf
The most ancient water-raising machine is the shaduf, a counterweighted lever from which a bucket is suspended into a well or stream. It appears in illustrations from as early as 2500 B.C. in Akkadian reliefs and is still in use today in parts of the Middle East.
- · Screw or Water Snail
Other traditional water-raising machines, introduced between the third and first centuries B.C., include the screw, or water snail, whose invention is attributed to the great mathematician Archimedes. It consists of a helical wooden blade rotating within a barrel like wooden cylinder, a design that could not push water up inclines greater than about 30 degrees, although 20 degrees was more common.
- · Noria
Higher lift was achieved by the noria, a large wheel driven by the velocity of the current. On the outer rim a series of compartments are fitted in between a series of paddles that dip into the water and provide the propulsive power. The water is scooped up by the compartments, or pots, and is discharged into a head tank or an aqueduct at the top of the wheel. Norias could be made quite large. The well-known wheels at Hama on the river Orontes in Syria have a diameter of about 20 meters. The noria is self-acting, and its operation thus requires the presence of neither man nor beast. It is, however, expensive to build and maintain.
- · Saqiya
The saqiya is probably the most widespread and useful of all the water-widespread and useful of all the water-rising machines that medieval Islam inherited and improved. It is a chain of pots driven by one or two animals by means of a pair of gears. The animals push a drawbar through a circle, turning an axle whose pinion meshes with a vertical gear. The gear carries a bearing for the chain of pots, or pot garland--two ropes between which earthenware pots are suspended. The chain of pots is optimal for raising comparatively small amounts of water from comparatively deep wells.
2. Windmill
The first windmill was invented in the seventh century in Afghanistan, where waterpower was lacking. The rotor turned on a vertical axis, a design that spread throughout much of Asia. The Muslims never adopted the European windmill, with its horizontal axis, although the Crusaders erected such windmills in their castles.
The more powerful vertical wheels came in two designs: undershot and overshot. The former is a paddle wheel that turns under the impulse of the current. The overshot wheel receives water from above, often from specially constructed channels; it thus adds the impetus of gravity to that of the current.
List of Mechanical Devices of Medieval Islam
1. Wind-powered fountain
In the 9th century, the Banū Mūsā brothers designed the earliest known wind-powered fountains. Their Book of Ingenious Devices described the construction of several wind-powered fountains, one of which incorporated a worm-and-pinion gear.
2. Mercury-powered automata
One of the clocks invented by Ibn Khalaf al-Muradi in 11th-century Spain incporated a "complicated and ingenious system which, at the top of each hour, puts into motion a series of mechanical automata, including mechanical snakes, women and men which function through a system based on water, mercury and pulleys.”
3. Programmable humanoid robot band
Al-Jazari (1136–1206) created the first recorded designs of a programmable humanoid robot in 1206, as opposed to the non-programmable automata in ancient times. Al-Jazari's robot was originally a boat with four automatic musicians that floated on a lake to entertain guests at royal drinking parties.
4. Peacock fountain with automated humanoid servants
Al-Jazari's "peacock fountain" was a sophisticated hand washing device featuring humanoid automata as servants which offer soap and towels.
5. Bayonet fitting
Al-Jazari's candle clock in 1206 employed, for the first time, a bayonet fitting, a fastener mechanism still used in modern times.
6. Boiler with tap
The Banu Musa brothers' Book of Ingenious Devices describes a boiler with a tap to access hot water. The water is heated through cold water being poured into a pipe which leads to a tank at the bottom of the boiler, where the water is heated with fire. A person can then access hot water from the boiler through a tap.
7. Bolted lock and mechanical controls
According to Donald Routledge Hill, Al-Jazari first described several early mechanical controls, including "a large metal door...and a lock with four bolts."
8. Conical valve
This was a mechanism developed by the Banu Musa and of particular importance for future developments. It was used in a variety of different applications, including its use as "in-line" components in flow systems, the first known use of conical valves as automatic controllers.
9. Crank-slider mechanism
A crank-driven water pump by Al-Jazari employed the first known crank-slider mechanism.
10. Elevated battering ram
In 1000, the Book of Secrets by the Arab engineer Ibn Khalaf al-Muradi in Islamic Spain described the use of an elevator-like lifting device, in order to raise a large battering ram to destroy a fortress.
11. Fountain pen
The earliest historical record of a reservoir pen dates back to the 10th century. In 953, Al-Muizz Lideenillah, the caliph of Egypt, demanded a pen which would not stain his hands or clothes, and was provided with a pen which held ink in a reservoir and delivered it to the nib, though the method of operation is unknown and no examples survive.
12. Gate operator
The first automatic doors were created by Hero of Alexandria and Chinese engineers under Emperor Yang of Sui prior to Islam. This was followed by the first hydraulics-powered automatic gate operators, invented by Al-Jazari in 1206.Al-Jazari also created automatic doors as part of one of his elaborate water clocks.
In the 9th century, the Banū Mūsā brothers invented a number of automata (automatic machines) and mechanical devices, and they described a hundred such devices in their Book of Ingenious Devices. Some of the devices that make their earliest known appearance in the Book of Ingenious Devices include:
- · Differential pressure
- · Double-concentric siphon
- · Fail-safe system
- · Float chamber
- · Float valve
- · Hurricane lamp
- · Self-feeding lamp and self-trimming lamp
- · Trick drinking vessels
- · Plug valve
- · Self-operating valve
Resources:
Mechanical Engineering in the Medieval Near East by Donald R. Hill
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