Al-Jazari's Third Water-Raising Device: Analysis of its Mathematical and Mechanical Principles

Five pumps or water-raising machines are described by al-Jazari in his monumental treatise of mechanics Al-Jami' bayn al-‘ilm wa 'l-‘amal al-nafi' fi sina'at al-hiyal (A Compendium on the Theory and Useful Practice of the Mechanical Arts). The following long article is a detailed study of the third of these water-raising devices. The study presents a detailed analysis of the mathematical and mechanical principles of this sophisticated machine and explains its functioning. Further, the various components of the pump are reconstructed via computer assisted design. A profusion of 3D graphics and 3D animations show the device in different angles and helps in viewing it in operational mode.

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By Salim T. S. Al-Hassani* and Colin Ong Pang Kiat**

Table of contents

Preface: Summary and Objectives of this Research

I. Characterisation of the tradition of Islamic Technology
  1. Beginning of Islamic Science and Technology
  2. Islamic Technology
  3. The Teaching of Islamic Engineering
  4. Comparison of Islamic and Modern Engineering Concept
  5. Transmission of Islamic Studies

II. Al-Jazari: Outline of his Biography and of his Work's Historical Context
  1. Al-Jazari's Life and Personality
  2. Al-Jazari's Work: The Book of Knowledge of Ingenious Devices
     2.1. Why is Al-Jazari's Work so Important?
     2.2. Why was there so Limited Works by other Scholars?

III. Water-Raising Devices: History and Technical Principles
  1. What Led to the Development of Water Raising Devices?
  2. Ancient Water Raising Devices
     2.1. The Shaduf
     2.2. The Archimedean Screw or Water-Snail
     2.3. The Noria
     2.4. The Saqiya

IV. Al-Jazari's Third Water-Raising Device
  1. A Revolutionary Idea
  2. Description of the Device
  3. Possible Problems Encountered

V. Research and Analysis
  1. Scoop-Wheel or Water Turbine
     1.1. How did al-Jazari Invent the Scoop-Wheel Design?
     1.2. Why did he Use the Scoop-Wheel Instead of the More Common Overshot Wheel?
     1.3. Why did he Convert the Undershot Scoop-Wheel to an Overshot Scoop-Wheel?
     1.4. Comparison between the Undershot Wheel and the Overshot Wheel?
     1.5. John Smeaton Experiment
  2. Cogwheel and Lantern Pinion Gears
  3. Analytical Interpretation of the Gears Found on al-Jazari's Illustration
     3.1. Why is it Elliptical in Shape?
     3.2. Why do the Gears have Sharpened Teeth?
     3.3. Possible Relationship to the Saqiya Gears
     3.4. What did the Actual Gears Look Like?
     3.5. Will the selected Gears be able to Transmit High Torque?
     3.6. What are the Methods Used to Enhance its Efficiency?
  4. Sindi Wheel
     4.1. Possible Problems Encountered?
     4.2. What are the Methods Used to Enhance its Efficiency?
  5. Where Does Water from the Lower Chamber Flow?
     5.1. Possibility 1
     5.2. Possibility 2
     5.3. Possibility 3
  6. Rudimentary Components and Materials Used by Al-Jazari
     6.1. Bearings
     6.2. Axle
     6.3. Lubrication
     6.4. Pipes
     6.5. Fittings
     6.6. Materials
     6.7. Jackwork or Jack Figures
  7. Weights and Measurements

VI. Mathematical Analysis

  1. Analysis of the Total Head of Water Jet
  2. Analysis of the System of the Third Water Raising Device
  3. Assumptions and Considerations
     3.1. Deflection Angle for the Bucket
     3.2. Maximum Weight Of Water Being Raised

VII. 3D Graphics and Animations
  1. Identification of Parts
  2. Front Perspective Close-Up View
  3. Rear Perspective Close-Up View

VIII. Conclusion

IX. References
  1. General
  2. References for Mathematical Analysis

* * *

Preface: Summary and Objectives of this Research

The following study investigates an ancient water raising device invented in the 13th century by an Islamic inventor and engineer, al-Jazari. This invention is known as the Third Water Raising Device, which is found in the important treatise of al-Jazari Kitab ma‘rifat al-hiyal al-handasiya (The Book of Knowledge of Ingenious Devices) [1]. We explore hereinafter thoroughly the origin and genius of the inventor, al-Jazari, and his invention, with in-depth research and discussion from the evolution of the invention to the rudimentary components used.

The study is composed of 7 chapters and 12 appendixes (which can be navigated by using the Table of Contents below). In addition, mathematical analysis and 3D animations of the system are also included to further aid the reader in understanding the concept of the invention.

Chapter I introduces a brief history on technology in Muslim heritage. The scope of interest is focused on the various branches of Islamic technology, its educational system and the possible transfer of knowledge to the West. A comparison of Islamic and modern engineering concepts is also investigated.

In Chapter II, the life and environment of the inventor, al-Jazari, and his factors of innovation are investigated. All of which contributed to the compilation of his important work, The Book of Knowledge of Ingenious Devices. The importance of al-Jazari’s work as an engineering document is attributed to the various ingenious components and concepts included, most of which are of relevance and are used in modern-day engineering.

In Chapter III, the origin and development of the ancient water raising devices are summarised. These devices were invented as early as 2500 BCE and were driven by either animal or water power. The relevance of some of these designs to al-Jazari’s invention are discussed in Chapter V.

In Chapter IV, the evolution of the inventions is discussed, followed by a description of the system of the inventions. The possible problems that might be encountered during its operation are also discussed. The technical and mechanical aspects of the inventions are discussed in Chapter V.

In Chapter V, components ranging from the large scoop-wheel to the rudimentary bearings that al-Jazari used are investigated and discussed. References are made to relevant components of the ancient water raising devices. The materials available and unit scales, which he used to define measurements, are also discussed.

In Chapter VI, the mathematical analysis of the system of the invention is derived and discussed. The formulas derived have been programmed into a Microsoft Excel programme to estimate the head of the water jet, the force capable of raising the water and the weight of the water raised.

In Chapter VII, 3D graphics and animations are constructed, using 3D Studio Max R3.1, based on the findings on the research and mathematical analysis done. The 3D animations consist of a 360° rotational view movie file and another one that shows the movement of individual components during its operation.

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Figure 1: A miniature depicting a traditional scene of instruction.

They also knew the book of Mechanica by Hero of Alexandria and the book of Pneumatica by Philo of Byzantium. These and other Greek and Alexandria works served as a basis for their research in this domain [10].

The Alexandria school teaches a series of writings on various mechanical devices, gadgets and automata. This branch of science is called the ‘ilm al-hiyal’ in Arabic and had attracted the imagination of Muslims, fascinated with the unusual, ‘ilm al-hiyal’ itself has always been related in the Muslim mind with the occult sciences and magic, as the word itself whose roots means stratagem or ruse, shows.

In addition, many Muslim scholars also learn from the works of their predecessors. In accordance, a series of works describing complicated machines and gadgets can be found in various important works. From the treatise of the Banu Musa on the balance ‘qarastun’, those attributed to Ibn Sina such as the ‘Mi‘yar al‘uqul’ (The Standard of the Intelligence), to the work of the 13th century AD author Ibn al-Sa‘ati who describe the clock of Damascus [11].

Another important feature of the thinking behind many of the devices described in the treatises is the preoccupation of the Arab engineers with controls, particularly with controls that would allow a given machine to continue working for a long period of time without human intervention [12].

The above mentioned might also be the basis of teaching for al-Jazari and he in turn will also contribute to this method of teaching through his work, ‘Kitab fi ma‘rifat al-hiyal al-handasiya’ (The Book of Knowledge of Ingenious Mechanical Devices).

The Book of Knowledge of Ingenious Mechanical Devices is a compilation of writing on automata and the like, which were a source of wonder and served as pastimes for princes and rulers. It consists of six parts, fifty complicated mechanical devices such as clepsydras and fountains, some of practical use and others more for amusement, following the tradition of the Alexandrines. The treatise was translated from Arabic into Persian as late as the 19th century and because of the variety of its content and beautifully illustrated manuscripts found in relative profusion, has become the best-known work of its kind in the West after it had been studied by historians of science and of art since the 19th century [13].

4. Comparison of Islamic and Modern Engineering Concept

There are a few areas whereby there is notable difference between Islamic and modern engineering concept, namely in what concerns the use of mathematical analysis, the lack of sufficient resources and the use of various sources of power. These are further elaborated as follows.

4.1. Calculation (Mathematical Analysis)

The assumption for the Modern Engineering Concept is that engineering tasks must be accompanied by rigorous mathematical analysis. Whereas in the Islamic Engineering Concept of the past, most of the mathematical relationships that underlie the physical phenomena had not been identified, and engineers had to draw upon a large fund of practical experience. This is to say that the Muslim engineers of antiquity most probably didn’t do many calculations at all and obtain the best results through trial and error methods.

Of course, not all the work of Muslim engineers was so laborious; they had a clear understanding of arithmetic, plane geometry, and measurement, and they used these sciences to the full in the construction and assembly of their devices. But when a set of mechanisms was particularly complex and delicate, final assembly and adjustment were done by painstaking trial and error [14].

4.2. Limited Resources

The Muslim engineers most probably needed to have at their command all the contemporary scientific and technical skills available in order to obtain the best possible results from the limited resources at their disposal.

4.3. Source of Power

The Modern Engineering uses fossil fuel, water pressure, air pressure, nuclear energy etc. for its source of power whereas Islamic Engineering was essentially bases only upon the use of the effects of water pressure and air pressure.

5. Transmission of Islamic Studies

Islamic Studies obtained most of its knowledge from various ancient civilisations (see Fig. 3), and subsequently the transmission of knowledge from Islamic Studies to Europe was mainly by literary means and occurred on a large scale. However, the situation is completely different for Islamic Engineering, there are very few works in Arabic dealing with engineering, and the treatises that have survived were never translated into Latin nor, until recent time, into any modern European language.

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Figure 2: Two shadufs used to raise water from a river in Egypt.

2.2. The Archimedean Screw or Water-Snail

The Archimedean Screw or Water-Snail was probably invented by Archimedes, its origin are datable to about 250 B.C. and by Roman times it was widely used [43]. It consists of a helical wooden blade rotating within a barrel-like wooden cylinder with the lower end of the screw dipping into the water source while the upper end discharges into an irrigation ditch. The angle of the screw therefore determines its water output (see Fig. 5).

However, unlike the Shaduf, the device has not retained its popularity although it was still in common use in Upper Egypt and other parts of the Arab world in 1965, but had since disappeared from the Delta region [44].

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Figure 3: A giant Noria Wheel at Hama, Syria.

2.4. The Saqiya

The Saqiya, which is driven by animal power, was almost certainly invented in Egypt in the third century BC [47], and was known by Roman times, from about the start of the Christian era. It is probably the most widespread and useful of all the water-raising machines that medieval Islam inherited and improved (see Fig 7).

It consists of a chain-of-pots or potgarland, driven through a pair of gears by an animal moving in a circle. The animal pushes a drawbar through the circle, turning an axle whose pinion meshes with a cogwheel gear. This gear then turns the chain-of-pots, which consists of suspended earthenware pots between two ropes, carrying water. The chain-of-pots is optimal for raising comparatively small amounts of water from comparatively deep wells [48].

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Figure 4: Another depiction of al-Jazari's pump for raising water in a manuscript of copy held in Topkapi Sarayi Libray in Istanbul. (Source).

2. Description of the Device [51]

The Third Water-Raising Device was intended as a decorative attraction near an ornamental lake [52], with an element of mystification about it. Thence an ornamental lake erects an elegant open structure, with only its automata working parts visible to spectators, thus leaving the spectators curious on how the device is powered (see Fig. 8).

Consider the nature of al-Jazari’s working environment, it is most likely erected in the King’s garden, where it caused wonder and aesthetic pleasure to courtly circles and raised water for irrigation to the garden at the same time.

It was however, simply an elegant development of a utilitarian device that was used for supplying water for irrigation and domestic purposes. A development of the Saqiya, having the main difference of the device being powered by waterpower instead of animal power.

The structure itself is quite small, being divided into 2 sections; the lower chamber whereby the water driven mechanism is ‘hidden’ under the ground and upper chamber whereby the automated mechanism above the pool was made visible.

It consists of a copper pool with an escapement, whereby water flows into the lower chamber and drives the Scoop-Wheel. The rotating Scoop-Wheel in turn rotates the Cogwheel and Lantern Pinion gears, driving the vertical hollow copper pillar with an iron stanchion beneath it. The rotating pillar in turn rotates the second set of gears in the upper chamber, driving the Sindi Wheel that raises water to the head tank (this is seen in Fig 8 and in the reconstructed depiction in Fig. 9) [53].

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Figure 5: A 3D graphic of the Overshot Scoop-Wheel.

The first description of the Scoop-Wheel was by Philo of Byzantium. In his work, he introduce a water-raising device whereby a chain of buckets is driven by an Undershot Wheel with a series of spoon-shaped spokes arranged in a circle around the hub (see Fig. 13). In addition, Philo remarks that the wheel “can be applied to many other uses” [61].

It seems that Al-Jazari might have studied Philo’s work [62] and noticed the ingenious Undershot Wheel of unusual design set up to work a string of pots by a chain drive [63]. Later, Al-Jazari improved on its design by converting it from an Undershot Wheel to an Overshot Wheel and later echoed Philo’s remark by incorporating the Scoop-Wheel design as part of his striking mechanism in his various devices [64].

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Figure 6: A small low-powered Pelton wheel of the 1890s.

1.1. How did al-Jazari Invent the Scoop-Wheel Design?

Assuming that al-Jazari was ignorant of Philo’s work, as we claimed earlier, then it would be a reasonable assumption that he derived his Scoop-Wheel design from the principle of the Overshot Wheel and the Noria, which had a wheel for lifting water with buckets scoops fixed to its outer rim. However, even though we consider that he had based this design on Philo’s work, he must had to rely on the mechanism of Scoop-Wheel to power his invention.

1.2. Why did he Use the Scoop-Wheel Instead of the More Common Overshot Wheel?

The reason is that Al-Jazari was interested only with the innovative and ingenious water wheels, whereas ordinary wheels, such as the Overshot Wheel, were taken for granted and evoked no interest [66]. However, it is interesting to note that according to John Smeaton’s experiments, impact between a stream of water and a flat plate resulted in a marked loss of energy in the form of spray and turbulence. Thence leaving us to wonder did al-Jazari know about this or was it by a stroke of luck that he happened to use the curvaceous Scoop-Wheel instead of the flat-plated Overshot Wheel?

1.3. Why did he Convert the Undershot Scoop-Wheel to an Overshot Scoop-Wheel?

As mentioned before, al-Jazari had expressed awareness for the need to develop machines with a better design and greater output than the traditional ones. He might have done experiments on his own and most probably obtained the similar results [67]. Furthermore, his concept of the invention is to hide the lower chamber of the driven mechanism, allowing only the flow of water down, hence the Overshot Wheel design would have been more appropriate in this case.

1.4. Comparison between the Undershot Wheel and the Overshot Wheel?

First of all, we know that both wheels have been around since Vitruvius (100 BCE) who described them in his work [68]. Next, we need to understand the working principles of these two wheels. The Undershot Wheel rotates by the pressure of the moving water, on the paddles of the lower part of the wheel (see Fig. 15). This means that it requires a considerable volume of water with a rapid flow, therefore a wasteful means of using waterpower [69]. Whereas the Overshot Wheel rotates by the pressure of water pouring from above onto the top paddles, thus a small volume of water is sufficient (see Fig. 16).

Finally, we need to know its supply of waterpower. Although the Overshot Wheel is technically more efficient [70], however it needed a constant supply of water from an aqueduct or if fed by sluggish rivers in a flat country demanded the construction of a millrace, a mill-pond and a chute plus sluice for proper manipulation. Whereas the Undershot Wheel, depended on swiftly flowing water and a fairly constant volume of water the whole year through to work efficiently [71].

Figure 7: The Vitruvian or Undershot Wheel. The wheel is turned by the pressure of moving water on the paddles of the lower parts of the wheel.

Figure 8: The Overshot Wheel is turned by the pressure of water pouring from above into the bucket-like compartments onto its rim.

1.5. John Smeaton Experiment

John Smeaton of England did an experiment (made public in 1759) on the efficiency of actual water wheels; namely the Undershot and Overshot Wheels. The first important result was that Overshot Wheels were about twice as efficient as Undershot Wheels; in modern terms the ratio was 66% efficient against 30%.

The second was that Overshot Wheels were driven by weight of water alone and perhaps a little more efficiency was gained by allowing the applied stream of water to strike hard against the buckets.

Lastly, it was noticed that the impact between a stream of water and a flat plate resulted in a marked loss of energy in the form of spray and turbulence. As Smeaton observed, “non elastic bodies, when acting by their impulse or collision, communicate only a part of their original power; whereas the other part being spent in changing their figure in consequence of the stroke” [72].

2. Cogwheel and Lantern Pinion Gears

The second set of mechanisms to moving would be the Cogwheel and Lantern Pinion gears (see Fig. 17). This mechanism consists of toothed wheels meshing at right angles; whereby the Cogwheel is the vertical gear and the Lantern Pinion is the horizontal gear. For this section, I will first describe the background of general Gearing, followed by a step-by-step analytical interpretation of the gears found on al-Jazari’s illustration of the Third Water-Raising Device (see Fig. 1 and 8).

The first description of the Gearing was first mentioned in the ‘Mechanics’ (the oldest-known engineering textbook) written by either Aristotle [Aristoteles of Stagyra (384 to 322 BCE)] or Straton [Straton of Lampsakos (pupil of Aristotle)], or both which dates to the Hellenistic era [73].

The evolution of gearing comes about from roughening the rims to reduce slippage and from this roughening, gears teeth evolved. This step may have taken some time, for cutting and filing a pair of toothed gear wheels, having the right number of teeth and transmitting rotation without jamming, is not an easy task [74].

That is to say, Gearing had been long known but rarely used because of the difficulty of making well-fitting gears [75]. However Gearing became common in the Golden Age, due to the developing technology, contributed by both Muslim scholars and craftsmen.

3. Analytical Interpretation of the Gears Found on al-Jazari’s Illustration

In his illustrations, al-Jazari draws his gears (see Fig. 17) as elliptical in shape and has sharp pointed teeth as gear teeth. This might have looked crude to modern viewers but al-Jazari wanted to show his devices through perspective and colourful illustrations. It is also important to consider that modern Engineering Drawing was not known then. We will now consider a step-by-step analytical interpretation of the gears.

Figure 9: A blown-up diagram of the gears as shown in al-Jazari’s illustration.

Figure 10: The transformation of the circle to the elliptical shape.

3.1. Why is it Elliptical in Shape?

The elliptical-shaped gear is actually a cylindrical shape tilted at an angle. For example, if you were to take a round shaped cup with its top facing you (see Fig. 18) and tilted it at an angle towards the sky, you will notice that the shape has changed to an elliptical shape (see Fig. 17).

The reason why al-Jazari wanted to draw the gears in such a way is that he might have wanted to show his drawings in an isometric view or 3D view/aspect.

3.2. Why do the Gears have Sharpened Teeth?

Consider the gears to be sharpened toothed, in mechanical terms there will be difficulties in getting them to work properly. Furthermore, it is difficult to transmit power efficiently in this manner. Thence it is concluded that at this point, when al-Jazari draw the gears (see Fig. 17), he did not want them to be constructed as shown but rather to portrait them as a drawing symbol of gears only.

3.3. Possible Relationship to the Saqiya Gears

At this point of research, it was found that the invention was a modification of the Saqiya whereby the main difference is that waterpower is used instead of animal power. There is a high possibility that the gears of the Saqiya (Cogwheel and Lantern Pinion gear) are incorporated into al-Jazari’s invention since other identical mechanisms of the Saqiya could be found in the invention, such as the Sindi Wheel.

To support this statement, we may compare the Saqiya and al-Jazari’s illustration of the Third Water-Raising Device (see Fig. 19-20).

Figure 11-12: Notice the similarity of the positioning of the gears inside the red marked box.

3.4. What did the Actual Gears Look Like?

By studying the colour illustration (see Fig. 1 and 8), it is observed that the gears might have been the Cogwheel and Lantern Pinion gear (see Fig. 21) the red-coloured gear might have most probably indicated the Lantern Pinion gear while the blue ones indicate the Cogwheel gear.

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Figure 13

Agriculture was very important in that period, therefore irrigation plays an important role. The Third Water-Raising Device might have a primary role in raising water to a higher level. At the same time, it could also employ a secondary role in providing irrigation in lower land through drainage from its lower chamber. Water flows out from the lower chamber into a drainage system for irrigation in lower lands.

The Third Water-Raising Device would be located along a steep slope incline whereby river water is rushed into the pool of the device through pipe 1 and later flows out from the lower chamber back into the river through pipe 2 (see Fig. 24).

This could result in the machine working at a very fast rate in order to accommodate the speed of the river water rushing in.

5.2. Possibility 2

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Figure 14

6. Rudimentary Components and Materials Used by Al-Jazari

Having a clear understanding of the main mechanism as discussed earlier leads us to find out more about the rudimentary components and materials used by al-Jazari in the construction of the Third Water-Raising Device. Components ranging from bearings to the materials used will be discussed as follows.

6.1. Bearings

Bearings have been used for wheels as early as the fourth millennium BCE in lower Mesopotamia. In addition, metal-to-metal bearings were already in use by the Romans and Greeks, in which Hero of Alexandria mention, in his Mechanics, an axle whose ends were sheathed in copper and ran in copper-covered bearings.

It is difficult to assess the standard of craftsmanship attained by al-Jazari in the manufacture and fitting of his axles and bearings, since he tells us so little about them. The bearings are usually shown as rudimentary components on some of the drawings, but then, so are many other parts that we know from the text, to have been made with great care and skill. It is quite likely that they were drawn conventionally, much as a modern designer will show pitch circles for the teeth of a cogwheel.

It is justifiable to say that al-Jazari was serious towards his works, therefore he must have took great care to ensure that his wheels were running true. In static balance, this care would have been wasted if there was too much play or friction in the bearings. Thence he categorised different kinds of bearings for different uses as follow:

  • bearings for small axles are called kharaza,
  • bearings which were inserted into the lower ends of vertical axles are called sukurruja,
  • wooden axles had iron 'acorns' (balluta) nailed to their ends, and these rotated in bearings called mukhula.
  • bearings for heavy-duty are called rukn, which simply means ‘support’.

Plain wooden bearings were said to be in use in the West up to the 14th century. If this is the case, then al-Jazari was considerably in advance of European technology in this respect, since all his bearings are metal-to-metal type. He used different types of bearings for different duties and had a special term for each one. Because of the great care he took in constructing and tuning his machines it seems probable that his bearings were at least adequate, particularly when it is remembered that in most cases, the loads for the devices were light and running speeds were slow [86].

6.2. Axle

Al-Jazari made his axles of wood, copper or iron depending on the duty, and the usual word for them is mihwar, although he occasionally uses non-technical words such as qadib (stick) or saffud (rod). The Banu Musa, Archimedes and al-Khuwarizmi also use the term mihwar [87].

6.3. Lubrication

Lubrication is equally ancient, dating back to Egypt in 1800 BC. An Egyptian wall painting shows 172 men transporting a colossus from a quarry on sledges, while one man pour oil or grease ahead of the base of the statue on which he rides. In addition, Egyptian chariots had plain grease-packed bearings, which were protected from sand by leather covers.

The curious point however is that none, not one, of the classical writers, including al-Jazari, makes any mention of lubrication. It could be that they found the process of lubrication to be too common and trivial to be included in their work [88].

6.4. Pipes

The closed pipe system is of interest because al-Jazari incorporates this system to bring in water from rivers to the pool of the invention. Thence it is important to know the characteristics of the closed pipe system. Firstly, the closed pipe system is less expensive as compared to open-channel aqueduct. However, it is much more difficult to construct and requires specialised skills. Moreover, it is subjected to frequent leaks and burst, and if blockage occurs, it may have to be completely dismantled and rebuilt [89].

However, al-Jazari and Ridwan used the expression barbakh, which means a short pipe of relatively large diameter. Ridwan tells us that pipes were made by bending sheet copper to a circular cross-section and soldering the edges together. Pipes were joined together by making the end of one wider than the end of the other, and pushing the two together. The wide end was called 'female', the narrow 'male', exactly as in modern technical parlance. When pipes were to be bent, they were first filled with lead, followed by bending and allowing the lead to melt out [90].

Vitruvius suggested a method to seal the joints, crude but practical. That is when the pipeline is complete, and the water is first let into it, some wood ash should be thrown into the tank at the supply end. This will find its way into any cracks or leaks in the system, and help clogs them up. ‘Grouting’ is the technical term [91].

6.5. Fittings

All the Islamic writers used similar methods of connections and fixings. The most common method is soldering, a very ancient technique, probably known 5000 years ago in Ur. Whereby nails, cotters, lugs, male-female joints and push-fit connections were also used extensively, including al-Jazari and Ridwan.

While other components such as wire (sharit) was usually made of copper, and chain (silsila) of copper or iron. Rope (habl) was made of hemp or stranded silk. The material used for making string (khayt) is seldom specified, except when it was made of silk. Hinges (namadhaj) were mentioned by al-Khuwarizmi, and were used by all the Islamic writers.

An interesting word, used frequently by al-Jazari, is shaziya, translated as 'activator', since it seems to be used for any small component, which activates another part of the mechanism. Cams, trip-lugs, push rods, etc. could all be described by this word [92].

6.6. Materials

Most of the materials used by al-Jazari are common to the other Islamic writers, with the some exceptions. The materials are categorised into two groups, namely Metals and Other Materials.

a. Metals

The common metals used are iron, lead, tin, gold, silver, copper, brass and bronze. Furthermore the mountains around Diyar Bakr have always been rich in metals. In 516/1122 a copper mine was discovered near Dhu al-Qarnayn. Iron was also plentiful [93]. Therefore these metals are available to al-Jazari, who employed them in the structure of his invention.

b. Other Materials

Al-Jazari had little interest in the use of non-metallic materials, most of which were common substances in everyday use. Wood occurs frequently, in wheels, axles and structural work. The use of lamination to produce a wheel that would not warp is of interest. Other materials used were cloth, leather, linseed oil, paints, paper, and papier mache. Papier mache was used for making Jack Figures when lightness was important, in this case, it would most probably be used for making the cow model.

6.7. Jackwork or Jack Figures

Jackwork refers to human and animal figures, and are found in the works of several Muslim craftsmen and engineers, including al-Jazari. It was thought that Muslims were generally particularly fond of these types of work, as it was some kind of toy.

Al-Jazari usually made them from beaten copper, beaten brass, wood, or papier mache. However, the detailed instructions for the manufacture of these figures are often omitted, apart from al-Jazari description of the manufacture of a copper ‘man’ (shakhs), found in Category II Chapter 7.2 of his work, Kitab fi ma‘rifat al-hiyal al-handasiya [94].

7. Weights and Measurements

There was a large number of weights and measures whose values fluctuated widely, depending upon the region, and even upon the choice of the individual craftsman. Ridwan, for instance, used the span of his own hand and the thickness of his own finger for taking measurements. There is little point, therefore, in making a detailed survey of these expressions and their values. Thence only indicative values can be given and these are derived directly from Wiedemann and Hauser.

a. Weights

1 Dirham = 3 gr
1 Mithqāl = 4.5 gr
1 ’Uqiya (Syrian) = 150 gr
1 Ratl (Damascus) = 1850 gr
1 Mann ≈ 1 kg

b. Measures

1 Dhirā‘ (cubit) = ½ metre
1 Shibr (span) = ½ Dhira = 25 cm.

The span is the distance between the tip of the thumb and the tip of the forefinger, when the hand is outspread. The abbreviation is sp.

The span consisted of 12 fingers, placed side by side (asba ‘ madmum). Each finger width was thus equivalent to 2 cm. The abbreviation is F. Sometimes the length of a finger (asba‘ maftūh) was used and this was equal to about 4 cm.

Small dimensions are given by the width of a barleycorn (sha‘īra). Laid 'belly to back' there were six barleycorns to 1 F. The sha‘īra was therefore equal to about 1/3 cm.

The small span (fitr) was the distance between the tips of the thumb and index finger, when outspread. This is taken to be about 16 cm.

AI-Jazari also uses the breadth of a fingernail (zufr) say about 1 cm. To indicate very small distances he uses the width of a nail-pairing (qulama) [95].

VI. Mathematical Analysis

1. Analysis of the Total Head of Water Jet

The purpose of this analysis is to find the total head of water. A set of detailed calculation and explanation can be found in Appendix 11. The formulas in Appendix 11 used for finding this force is simplified and derived as shown below. These formulas are also programmed into Microsoft Excel programme to calculate the total head for variable conditions.

The Total Head of Water Jet:

HT = HW + HAB – [(tanθ)(rscoop)]

Where

HW = head of water surface to bottom of pool

HAB = half the height of the lower chamber

Θ = angle of strike

rscoop = radius of scoop-wheel.

The above variables are to be inputed into the Microsoft Excel programme for an estimation of the total head of water jet.

2. Analysis of the System of the Third Water Raising Device

The purpose of this analysis is to find the resulting force capable of raising water. A set of detailed calculation and explanation can be found in Appendix 12. The formulas in Appendix 12 used for finding this force is simplified and derived as shown below. These formulas are also programmed into the Microsoft Excel programme to calculate the force for variable conditions.

The force of the water jet:

Fj = 2 g HT ρ π(rj)2

The force transfer from the jet to the bucket:

FT = 2 g HT ρ π(rj)2 (1 – V*)(1 – cos θ)

The force applied on gear A:

FA = {(1 – μ) [(1 – μ)FT rscoop]} / rA

The Force applied on Gear B

FB = (1 – μ)FA

 

The Force applied on Gear C

FC = [(1 – μ) (FB rB)] / rC

The Force applied on Gear B

FD = (1 – μ) FC

The Force applied on Sindi Wheel

Fsindi = [(1 – μ) (FDrD)] / rsindi

 

The Weight of Water Raised:

mwater = Fsindi / g

where

HT = total head of water jet

ρ = density of water

rj = radius of jet outlet

V* = scaled bucket speed

= deflection angle for the bucket

= coefficient of friction

rscoop = radius of scoop-wheel

rA = radius of Gear A

rB = radius of Gear B

rC = radius of Gear C

rD = radius of Gear D

rsindi = radius of sindi wheel

The above variables are to be inputted into the Microsoft Excel programme for an estimation of the force capable of raising water and the weight of water raised.

3. Assumptions and Considerations

For the mathematical analysis of the system, several assumption and considerations were taken for the most optimal conditions. The more significant ones are the deflection angle for the bucket, θ, and the maximum weight of water being raised.

3.1. Deflection Angle for the Bucket

The typical deflection angle for the bucket is taken at the most optimal condition when it is at the horizontal position, where θ 1 is equal to θ 2 (see Fig. 27). However the deflection angle will vary as the bucket rotates, at this point, θ 1 is not equal to θ 2 (see Fig. 28). Although a more accurate force might be obtained by calculating this difference, it is noted that the difference in θ will be minute and that using the typical value of 165° is more appropriate.

Figure 15: The bucket in horizontal position during rotation.

Figure 16: The bucket deflected at angle during rotation.

3.2. Maximum Weight of Water Being Raised

Once the force capable of raising water is found, the maximum weight of water being raised can be found by Fsindi = mwaterg, on the assumption that the weight of the copper jars are in equilibrium or symmetry is maintained during the cycle, m1r1 = m2r2 (see Fig. 29). This is attributed to the fact that the weight of the copper jars would counter-balance, thence would be equilibrium.

However, it would not be true when the copper jars are in motion as there would be a difference in moment, m1r1 ≠ m2r2 (see Fig. 30). An opposing torque, TO, will therefore be applied against the torque produced by the force applied on the Sindi Wheel, Tsindi. Therefore the torque applied to raised water, Tw = Tsindi – To.

Although a more accurate value of the weight of water might be obtained by calculating this difference, it is noted that the difference will be minute and that using the formula Fsindi = mwaterg, is more appropriate.

Figure 17: The copper jars in symmetry.

Figure 18: The copper jars during rotation.

VII. 3D Graphics and Animations

Visual aids such as 3D graphics and animations play a very important role in this report, as they show a clearer picture of the device to the reader. 3D graphics and animations are constructed, using 3D Studio Max R3.1, based on the findings on the research and mathematical analysis done (see Fig. 31). These graphics and animations are used in the report as visual aids for better understanding of the device.

The 3D graphics in this chapter shows the device in different angles of views, close-up views and ‘wireframe’ views (see Figures 32 to 42). The different angles of views include the front perspective view, rear perspective view, front view and left view. The close-up view zoom in onto the chambers of the device in perspective view while the ‘wireframe’ view shows the ‘skeleton’ view of the device.

The 3D animations consist of two movie files; namely a 360° rotational view and one that shows the movement of individual components during its operation. These animations enable the reader to view the device in different angles and also the view of the device in operational mode.

Click here to view the animation.

Figure 19: 3D Construction of the Third Water Raising Device.

 

Figure 20: Front Perspective View.

Figure 21: The Rear Perspective View.

1. Identification of Parts

Figure 22: The identification of different parts of the Third Water Raising Device.

Figure 23: The Close-Up View of the Upper Chamber.

Figure 24: The Close-Up View of the Lower Chamber.

3. Rear Perspective Close-Up View

Figure 25: The Close-Up View of the Upper Chamber.

Figure 26: The Close-Up View of the Lower Chamber.

Figure 27: The Front View.

Figure 28: The Left View.

Figure 29: The ‘Wireframe’ Front View.

Figure 30: The The ‘Wireframe’ Rear View.

VIII. Conclusion

The flourishing of Islamic Studies was attributed to the success of the developing technology, which utilised natural forces within the environment to do work. Islamic technology was branched into Fine Technology and Utilitarian Technology. The Third Water Raising Device incorporated these two branches together, an ingenious invention by al-Jazari.

Al-Jazari was an inventor who described in scrupulous detail how each device was constructed. He was also a ‘ra’īs al-a‘māl’, which in modern terms is a “Chief Mechanical Engineer’. He reached this superior position on the basis of his extensive experience; having profound understanding of pure science on the one hand, and his mastery of practical skills on the other. In his treatise A Compendium on the Theory and Practice of the Mechanical Arts, emphasises the importance of experimentation and precise observation and will not entertain much faith in findings unsubstantiated by experiment.

The Third Water Raising Device is an example of his detailed description with constant reference to the drawing depicting the device. However, on occasions, he tends to be inconsistent in his dimensions, inability to give a coherent record of mathematical or geometrical process and having some vagueness about the positioning of the components. An interesting feature in this machine is the wooden animal that is fixed to the rotating circular disc giving the impression that this machine is driven by an ox. This is, perhaps, a way of avoiding being accused of designing a machine driven by some witchcraft or a jinni. Another explanation is that this machine is designed to work on both modes; automatic or animal driven, although there is no description of the latter mode.

Based on al-Jazari’s description, the construction of 3D graphics of the device began. However, problems were faced as he fails to state the kind of gears and rudimentary components that he might have used. Furthermore, he fails to mention several dimensions, such as the overall size of the device. In addition, the unit scales that he had used were ancient Arabic units. Thence research work had to be done to answer these queries.

A mathematical analysis of the system is also essential to analyse the overall capability of the device. According to the mathematical analysis, the system is capable to produce large force to raise relatively large amount of water. The formulas used are simplified and programmed into Microsoft Excel programmes for variable condition analysis.

Based on these findings, 3D graphics and animations were constructed and dimensions that were omitted initially were estimated instead. The 3D graphics and animations brought to life the device in working condition, where the movement of each component was estimated from the mathematical analysis. Furthermore, the 3D graphics and animations were used as visual aids in this report for better understanding of the device.

The Third Water Raising Device is relatively small in size as compared to al-Jazari’s other water raising devices. Expensive materials such as copper, silk and marble were used for the construction to enhance its appearance. However, the device is designed to raise relatively small amount of water as al-Jazari states that each copper jar would carry only 9 grams of water.

One may argue that the device might be unrealistic, with the use of heavy and expensive components such as copper jars that might affect the overall efficiency of the system. Furthermore, it is unrealistic to employ the use of a large amount of water to drive a device that raise a relatively small amount of water. However it is important to state that the device described in al-Jazari’s book was a small demonstration model invented for the courtly circle.

In conclusion, although the Third Water Raising Device has several doubtful faults in modern engineering terms, it might be considered as a technology breakthrough during the 13th century. Considering that this device incorporates the use of waterpower to drive a series of gears and finally the Sindi Wheel to raise water, an automated process that requires the presence of neither man nor animal. A success attributed to the ingenious inventor and engineer, al-Jazari.

IX. References

1. General

  • Agius, Dionisius A. & Hitchcock, Richard (editors), The Arab Influence in Medieval Europe: Folia Scholastica Mediterranea. Ithaca Press, 1994.
  • Al-Hassan, Ahmad Y., Hill, Donald R., Islamic Technology: An Illustrated History. Cambridge. Paris/Cambridge: UNESCO/ Cambridge University Press, 1986.
  • Al-Jazari, Ibn Al-Razzaz, The Book of Knowledge of Ingenious Mechanical Devices. Translated and Annotated by Donald R. Hill. Dordrecht: D. Reidel, 1974.
  • Al-Jazari, Al-Jāmi‘ bayn ‘l-‘ilm wa ‘l-‘amal al-nāfi‘ fī sinā‘at al-hiyal [A Compendium On The Theory And Practice Of The Mechanical Arts]. Arabic text edited by A. Y. al-Hassan et al. Aleppo: Institute for the History of Arabic Science, 1979.
  • Cursetji Pavry, Jal Dastur (editor), Oriental Studies in Honour of Cursetji Erachji Pavry. London: Oxford University Press, 1933.
  • Forbes, R. J., Studies in Ancient Technology. Volume 2 . Leiden: E. J. Brill, 1965.
  • Glick, Thomas F., Islamic And Christian Spain in The Early Middle Ages. Princeton: Princeton University Press, 1979.
  • Hayes, John R. (editor), The Genius of Arab Civilization Source of Renaissance. Oxford: Phaidon Press, 1976 (reeditions London: Escovitz, 1983; Cambridge, Mass.: The MIT Press, 1978, 1984).
  • Hill, Donald R., "A Treatise on Machines by Ibn Mu‘ād Abū ‘Abdallāh al-Jayyānī." Journal for the History of Aarabic Science vol. 1 (1978): pp. 33-44. [See also on the same text A. I. Sabra, A.I., "A note on Codex Medicea-Laurenziana Or. 152", Journal for the History of Arabic Science vol. 1 (1977): pp. 276-283].
  • Hill, D. R., A History of Engineering in Classical and Medieval Times. London/New York: Routledge, 1984.
  • Hill, D. R., Islamic Science and Engineering. Edinburgh: Edinburgh University Press, 1993.
  • Hill, D. R., Studies In Medieval Islamic Technology. From Philo to al-Jazarī−From Alexandria to Diyār Bakr. Edited by David A. King. (Variorum Collected Studies Series). Aldershot, Eng. /Brookfield, Vt.: Ashgate, 1998.
  • Landels, J. G., Engineering in the Ancient World. London: Chatto and Windus, 1980 (1st edition 1978).
  • Nasr, Seyyed Hossein, Islamic Science: An Illustrated Study. Photographs By Roland Michaud. London: The World of Islam Festival Trust, 1976.
  • Smith, Norman, Man And Water: A. History of Hydro-Technology. London: Peter Davies, 1976 (1st edition New York: Scribner, 1975).
  • Sprague De Camp, L., The Ancient Engineers. Garden City, N.Y.: Doubleday, 1963.
  • Usher, Abbott Payson, A History of Mechanical Inventions. Cambridge, Mass.: Harvard University Press, 1954. (Revised edition: Dover Publications, 1988).

2. References for Mathematical Analysis

  • White, Frank M., Fluid Mechanics. Third Edition. Maidenhead, Berkshire: McGraw-Hill Higher Education, 1994. (5th revised edition, 2003).
  • James M. Gere, Stephen P. Timoshenko, Mechanics of Materials. 4th Edition. Boston: PWS Pub. Co., 1984.
  • Joseph E. Shigley, Charles R. Mischke, Mechanical Engineering Design. Fifth Edition. McGraw-Hill, 1989.

End Notes

[1] The treatise survived under another title: Al-Jāmi‘ bayn ‘l-‘ilm wa ‘l-‘amal al nāfi‘ fī sinā‘at al-hiyal,. [A Compendium On The Theory And Practice Of The Mechanical Arts]. For more details, see FSTC, 800 Years Later: In Memory of Al-Jazari, A Genius Mechanical Engineer.

[2] Even though the machinery in the lower level was hidden from viewers and the cow was a wooden dummy, the pump was an entirely automatic design, powered either by the water turbine in the lower level, the upper horizontal axle drove the sindi wheel carrying the yellow belt with its attached water-pots to lift water to the upper level.

[3] For more details, see Appendix 1.

[4] Ahmad Y. al-Hassan & Donald R. Hill, Islamic Technology: An Illustrated History. Cambridge. Paris/Cambridge: UNESCO/ Cambridge University Press, 1986, p. 19.

[5] Ibid, p. 8.

[6] Ibid, p. 147.

[7] S. H. Nasr, Islamic Science: An Illustrated Study. Photographs By Roland Michaud. London: The World of Islam Festival Trust, 1976, pp.147-150.

[8] L. Sprague De Camp, The Ancient Engineers. Garden City, N.Y.: Doubleday, 1963, p. 283.

[9] Dionisius A. Agius & Richard Hitchcock (editors), The Arab Influence in Medieval Europe: Folia Scholastica Mediterranea. Ithaca Press, 1994, p. 25.

[10] S. H. Nasr, Islamic Science: An Illustrated Study, op. cit., p. 144.

[11] Ibid, p. 145.

[12] D. A. Agius & R. Hitchcock (editors), The Arab Influence in Medieval Europe, op. cit., p. 30.

[13] S. H. Nasr, Islamic Science: An Illustrated Study, op. cit., p. 145.

[14] John R. Hayes (editor), The Genius of Arab Civilization Source of Renaissance. Oxford: Phaidon Press, 1976, p. 180.

[15] Donald R. Hill,Islamic Science and Engineering. Edinburgh: Edinburgh University Press, 1993, pp. 226-227.

[16] Ibid, pp. 228-229.

[17] Ibid, p. 235.

[18] For more details on al-Jazari’s life, environment and the historical context of his work, see below Appendixes 3-5.

[19] D. R. Hill, Studies in Medieval Islamic Technology. From Philo to al-Jazari−From Alexandria to Diyar Bakr. Edited by David A. King. (Variorum Collected Studies Series). Aldershot, Eng. /Brookfield, Vt.: Ashgate, 1998, Category XV, p. 253.

[20] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 12.

[21] J. R. Hayes (editor), The Genius of Arab Civilization Source of Renaissance, op. cit., p. 177.

[22] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category I, p. 22.

[23] J. R. Hayes (editor), The Genius of Arab Civilization Source of Renaissance, op. cit., p. 177.

[24] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 10.

[25] See Appendix 2.

[26] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category XV, pp. 254-255.

[27] Al-Jazari, The Book of Knowledge of Ingenious Mechanical Devices. Translated and Annotated by Donald R. Hill. Dordrecht: D. Reidel, 1974, Devices, Part III, p. 279.

[28] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category XV, pp. 254-255.

[29] Ibid, Category II, p. 224.

[30] Ibid, Category XV, pp. 254-255.

[31] See Appendix 4.

[32] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category II, p. 224.

[33] Ibidem.

[34] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 37.

[35] See Appendix 6.

[36] D. R. Hill, A History of Engineering in Classical and Medieval Times. London/New York: Routledge, 1984, p. 145.

[37] See Appendix 7.

[38] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., pp. 206-207. See also Appendix 7.

[39] Ibid.

[40] Detailed explanations of the parts and working principles of the ancient water-raising devices are given in Appendix 8.

[41] D. R. Hill, Islamic Science and Engineering, op. cit., p. 92.

[42] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 38. See also The Shaduf Project: A European Commission Report on Mediterranean Shaduf Use and History.

[43] Norman Smith, Man And Water: A. History of Hydro-Technology. London: Peter Davies, 1976, p. 12.

[44] D. R. Hill, Islamic Science and Engineering, op. cit., pp. 92-93.

[45] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category I, p. 13.

[46] Jal Dastur Cursetji Pavry (editor), Oriental Studies in Honour of Cursetji Erachji Pavry. London: Oxford University Press, 1933, p. 238.

[47] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category I, p. 13.

[48] D. R. Hill, A History of Engineering in Classical and Medieval Times, op. cit., pp. 138-139.

[49] D. R. Hill, Islamic Science and Engineering, op. cit., p. 97.

[50] Thomas F. Glick, Islamic And Christian Spain in The Early Middle Ages. Princeton: Princeton University Press, 1979, p. 238.

[51] For al-Jazari’s detailed description on the design, working principle and materials used for this device, see Appendix 9.

[52] J. R. Hayes (editor), The Genius of Arab Civilization Source of Renaissance, op. cit., p. 182.

[53] More details of the working of al-Jazari's machine are given in Appendix 10.

[54] D. R. Hill, A History of Engineering in Classical and Medieval Times, op. cit., p. 148.

[55] See Chapter V, section 3: Sindi Wheel.

[56] J. G. Landels, Engineering in the Ancient World. London: Chatto and Windus, 1980, pp. 71-72.

[57] D. R. Hill, A History of Engineering in Classical and Medieval Times, op. cit., p. 128.

[58] See Appendix 11.

[59] D. R. Hill, A History of Engineering in Classical and Medieval Times, op. cit., pp. 144-145.

[60] D. R. Hill, Studies In Medieval Islamic Technology, op. cit., Category VIII, p. 4.

[61] L. Sprague De Camp, The Ancient Engineers, op. cit., pp. 146-147.

[62] See I. 3: Teaching of Islamic Engineering.

[63] Abbott Payson Usher, A History of Mechanical Inventions. Cambridge, Mass.: Harvard University Press, 1954, p. 163.

[64] L. Sprague De Camp, The Ancient Engineers, op. cit., p. 282.

[65] Al-Jazari, The Book of Knowledge of Ingenious Mechanical Devices, op. cit., Part III, p. 275.

[66] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 70.

[67] See section V.1.5: "John Smeaton Experiment".

[68] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 6.

[69] A. P. Usher, A History of Mechanical Inventions, op. cit., pp. 163-164.

[70] See section V.1.5: "John Smeaton Experiment".

[71] R. J. Forbes, Studies in Ancient Technology. Leiden: E. J. Brill, 1965, vol. 2, p. 42.

[72] Norman Smith, Man And Water: A. History of Hydro-Technology, op. cit., pp. 155-156.

[73] L. Sprague De Camp, The Ancient Engineers, op. cit., pp. 119-120.

[74] Ibid, p. 120.

[75] Ibid, p. 282.

[76] D. A. Agius & R. Hitchcock (editors), The Arab Influence in Medieval Europe, op. cit., p. 38.

[77] Th. F. Glick, Islamic And Christian Spain in The Early Middle Ages, op. cit., p. 237.

[78] See Appendix 8.

[79] Note on fig. 22 and 23 the similarity between these two devices as marked in red.

[80] A. Y. al-Hassan & D. R. Hill, Islamic Technology, op. cit., p. 39.

[81] Ibid, pp. 40-41.

[82] See Chapter III, section 2: The Noria.

[83] D. R. Hill, A History of Engineering in Classical and Medieval Times, op. cit., p. 138.

[84] Th. F. Glick, Islamic And Christian Spain in The Early Middle Ages, op. cit., p. 237. One cubit = 20 inches as stated in L. Sprague De Camp, The Ancient Engineers, op. cit., p. 68.

[85] See IV.2: Description of the Device.

[86] Al-Jazari, The Book of Knowledge of Ingenious Mechanical Devices, op. cit., Part III, pp. 275-276.

[87] Ibidem.

[88] Ibidem.

[89] J. G. Landels, Engineering in the Ancient World, op. cit., p. 42.

[90] Al-Jazari, The Book of Knowledge of Ingenious Mechanical Devices, op. cit., Part III, p. 276.

[91] J. G. Landels, Engineering in the Ancient World, op. cit., p. 44.

[92] Al-Jazari, The Book of Knowledge of Ingenious Mechanical Devices, op. cit., Part III, p. 277.

[93] Ibidem.

[94] Ibidem.

[95] Ibid, p. 278.

* Foundation for Science, Technology and Civilisation, Chairman of the Board, and Emeritus Professor at the University of Manchester.

** Final Year Student (2001), Mechanical Engineering, MACE, University of Manchester, UK.

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