אל ג’זארי

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The pump and the Crankshaft

Introduction

The fourth machine for raising water is a pump based on a slider-crank mechanism. A more detailed explanation about crank, its history, and why is it interesting will follow. Since the drawing by al-Jazari is difficult to understand, I will present the revised drawing by Dr. Donald R. Hill, The book translator, and annotator. This is a good opportunity to write a few words about Hill, who was instrumental in bringing this book to us and in understanding al-Jazari and his importance to the history of Engineering.

Machine for raising water from a pool, Chester Beatty Library in Dublin probably 15th century from Iran or Iraq

Donald Rutledge Hill (1922-1994)

Hill was born in London. He joined the English army engineering unit during World War II until he was wounded in action in Italy. Back in England, he studied Engineering at the London University, obtaining his engineering degree in1949. He later worked for the Iraq Petroleum Company in Lebanon, Syria, and Qatar. Hill was gifted in languages, and before arriving at the Middle East, he was already fluent in French, German, Spanish and Italian. The move allowed him to add spoken Arabic but also to master literary Arabic. In 1964 he completed an M.Litt in the history of Islam and 1970 a Ph.D. from the University of London. His impressive accomplishments are a result of the unique combination of engineering knowledge and mastery of Arabic as well as Orientalism at its best, the study of the Arabic culture rather than a romantic perception or in contrast to the West. His main contributions are the translations of “The Book of Knowledge of Ingenious Mechanical Devices,” by al-Jazari, which is the sole purpose of this blog. He also translated the “Banu Musa” mentioned here more than once, and “On the Construction of Water Clocks” attributed to Archimedes. His contribution far exceeds the traditional role of a translator and includes annotations, drawings and writing several books on the history of engineering and technology that helped reinstate the technology in the golden age of Islam to its proper place.

How does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in Cranks (Are you series? Without Cranks we would not have locomotives or cars!) Or toothed wheels can skip those bits

An ox, in the upper room, is rotating the system. If you are confused after the fake cow, in the previous post, this is an actual animal, and without it, the pump would not work. The part of the gears and the conversion of the rotary movement to a linear one is difficult to understand (for me and others), and it looks like al-Jazari drawing is in error. I bring side by side the original illustration by al-Jazari and the drawing by Hill, and I added captions.

Combined drawing, al-Jazari, and Hill

The Ox, in the top room, rotates the horizontal tooth-wheel, which in turn rotates a vertical tooth-wheel, much like the classic sāqīya already explained here. The difference is that the vertical tooth wheel is attached to a slider-crank. We met this mechanism in the water wheel pump where it converted circular motion to linear motion and possibly vice versa. This is an essential component in engines and pumps till this very day. This is an animation of the pump, and you can see the slider-crank mechanism clearly:

It is easy to see that when the wheel rotates the crank moves within the slot and since the ladle is anchored at the axle it will raise the water and empty them later. In al-Jazari drawing( in contrast to the text which is quite clear) it seems that the vertical tooth-wheel is in 900 and the crank is in an odd angle relative to the slot. Hill’s drawing is correcting all these problems and explains well how it worked. Large engines are usually multicylinder to reduce pulsations from individual firing strokes, with more than one piston attached to a complex crankshaft:

Flat-plane crankshaft (red), pistons (gray) in their cylinders (blue), and flywheel (black)

Crankshaft

Many internet sites consider the crank as an invention of al-Jazari, for example here:

“In 1206, al-Jazari invented an early crankshaft, which he incorporated with a crank-connecting rod mechanism in his twin-cylinder pump. Like the modern crankshaft, al-Jazari’s device consisted of a wheel setting several crankpins into motion, with the wheel’s motion being circular and the pins moving back-and-forth in a straight line. The crankshaft described by al-Jazari transforms continuous rotary motion into linear reciprocating motion and is central to modern types of machinery such as the steam engine, internal combustion engine, and automatic controls. “

Before I expand a little on the evolution of the crank, it is important to note that the concept of an individual inventor is, in most cases, excessive romanticizing. It is inordinate when we have a definite inventor and more so for the Middle Ages or before that.  Take, for example, James Watt, who invented the steam engine in 1769 and issued a patent for it. A few children’s books suggest the idea of the steam engine came at the age of 12 while young James sat in the kitchen with his aunt, staring at a teakettle. The water was boiling so hard that the lid of the tea kettle began to jump up and down. This is simply not true. Watt invented the steam engine while fixing Newcomen’s steam engine for the University of Glasgow. This engine was invented in 1712 and was considered a great success. More than 100 such engines were installed as water pumps in mines in England and Wales. Also, the Newcomen engine is not the first steam engine, and there are predecessors from the 16th and 17th centuries. Don’t get me wrong, James Watt is entirely worthy of his glory, his improvements (the separate steam condenser and later the double-action engine) were very significant and the industrial revolution, for better or worse, is the consequence of the improvements by Watt.

The electric light bulb was invented by Edison, and the airplane was invented by the Wright brothers, but their story is not very different from the story of James Watt. Without diminishing their impotent contributions, their inventions, just like Watt’s steam engine, are a link in a long chain.

Manual cranks appeared in China during the Han dynasty (202 BC-220 AD), and we find ceramic models in the tombs of the period. However, the potential of the crank of converting circular motion into reciprocal motion never seems to have been fully realized in China. There are manual cranks examples from Europe and the Middle East. For example this picture of Roman iron crank for an unknown purpose from the 2nd century AD

roman crank

A Roman iron crank dating to the 2nd century AD was excavated in Augusta Raurica, Switzerland.

The crank appears in the book by the Banu Musa from the 9th century, which al-Jazari new and quoted. However, in their version, the crank did only a partial rotation which wouldn’t allow for significant power transfer.  Al-Jazari did not write, as he did in his fountain [in Hebrew], for example, that he looked at design by the Banu Musa and decided that it requires improvement and does not refer to the originality of his design.

330px-Steam_engine_in_action

Steam Engine, Wikipedia

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Formulas are holy and the automaton of a standing slave holding a Fish and A Goblet

“Troubles overcome are good to tell” – “Ibergekumene tsores iz gut tsu dertsyln.” Yiddish proverb by Primo Levi, “Periodic Table”

Introduction

The automaton is one of the simpler al-Jazari’s designs, but the description, like many other descriptions in the book, is intriguing not to say mesmerizing.

“He is a standing slave, ten years old in appearance, dressed in a short jacket with a rob underneath it, and a cap on his head. In his right hand is a glass the fingers curled around the bottom of the glass so that it can be taken out of his hand and put back… His left hand is in the same position, but higher than the glass, and holds a silver fish.”

Drawing of the Automaton with the fish and the goblet, Topkapi, 1206

The fish is surprising.  As far as I know, the fish is a Christian symbol, because of the miracle of the five loaves and two fish, because fishermen like Simon, Peter, Andrew, and John were the followers of Jesus later to become the apostles. Ichthus (Greek ΙΧΘΥΣ) the fish symbol is an acronym for Iēsous Christos, Theou, Yios, Sōtēr; in English:”Jesus Christ the son of God, Savior” has become a sign of recognition among persecuted Christians. The connection between wine and fish reminded me of a fascinating conversation between in varnish makers in the story “Chromium”  from the book “The Periodic Table”  written by Primo Levi; I will elaborate below.

How does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in copper hammering or tipping bucket can skip those bits.

This chapter has only one drawing, the one that appears above. Perhaps because this automaton is so simple. On the other hand, there are detailed explanations on the fabrication process:

“If the craftsman is not competent enough to make the face by hammering he can make [various] parts thicker with lead, e.g. the nose, etc.”

Also:

“The craftsman should not be afraid that the slave will tilt in any direction. I made him and placed the soles of the feet on the ground, and was afraid that he would tilt, but when he was standing erect he did not tilt at all.”

I took the liberty to take the original drawing of  al-Jazari and make it more like a contemporary drawing which clarifies the mechanism of the automaton:

The mechanism of the automaton, a slave with a goblet and a fish. My drawing

The upper part of the automaton, the head, and the chest is a wine reservoir. Its filling opening is hidden under the cap of the slave. At the bottom of the reservoir, there is a small drain above a tipping bucket. Al-Jazari often used tipping buckets. We met them already here (Hebrew), and we will meet more in future posts. Initially, the tipping bucket is leveled, as shown in the drawing, but after seven and a half minutes it is filled with wine towards its tip, and the bucket tilts and discharges all the wine through the pipe to the hollow silver fish. The silver fish is mounted on an axle, and its lower part is slightly heavier, so the fish is tilted upwards. With the wine,  the fish head becomes heavier and sinks until it is near the goblet and the wine flows into the goblet. Under the weight of the wine, the arm of the slave descends as if he were offering the glass to the king. The king takes the glass, drinks from it, and returns it to his hand, which has risen to its previous position. This repeats every seven and half minute intervals until the reservoir is empty.

“Chromium” by Primo Levi or removing the onion from the varnish

Primo Levi, a wonderful Italian author, his best-known works are related to his personal life story as a Holocaust survivor like “If This Is Man”, “The Truce” and others, but I particularly like the “The Periodic Table”. In my defense I am (also) a chemist  and Primo Levi himself wrote:

“I write because I am a chemist. My trade has provided my raw material, the nucleus to which things join … Chemistry is a struggle with matter, a masterpiece of rationality, an existential parable … Chemistry teaches vigilance combined with reason.”

Many of my students of chemistry, physics and computational science, to their surprise I should  say, heard me over the years reading the story “Chromium” from “The Periodic Table” which opens:

“The entrée was fish, but the wine was red. Versino, head of maintenance, said that it was all a lot of nonsense, provided the wine and fish were good; he was certain that the majority of those who upheld the orthodox view could not, blindfolded, have distinguished a glass of white wine from a glass of red… Old man Cometto added that life is full of customs whose roots can no longer be traced… I made a rapid mental review to be sure that none of those present had as yet heard it, then I started to tell the story of the onion in the boiled linseed oil. This dining room, in fact, belonged to a company of varnish manufacturers. “

The story begins in a prescription book for varnish. Advice is given to introduce into the boiling oil two slices of onion, without explanation or purpose and ends with ammonium chloride in a chromate-based anti-rust paint. For those who do not speak “chemistry” as a native language both are absurd. The weird and wonderful story is the essence of what is science and technology. I will explain the story of the onion, briefly but one who wants really to indulge in the story should read “The Periodic Table”. The onion was inserted into the oil before thermometers were used. When the onion started frying it indicated the proper temperature was reached and it is time to end the boiling process. Over the years varnish manufacturers switch to thermometers but forgot the original reason for using the onion and did not dare to deviate from the recipe they knew. This is how the recipe found its way to the book. When I read about the automaton of al-Jazari, I remembered this conversation and was wondering if they drank from the fish white or red wine?  What do we know about the drinking habits in the twelfth century? Apparently quite a bit.

Drinking habits in the twelfth century

For many years diners were isolated from wine drinking sessions. In ancient Greece, the Symposium (Greek: συμπίνειν, = to drink together) was a feast which took place after dinner. Drinking for pleasure was accompanied by music, dancing, or a good conversation. The modern use of symposium as an academic scholarly discussion is quite different. Although the Romans drank during dinner, wine mixed with water, they had a separate drinking party (comissatio) after dinner. Similarly, Arabic-Islamic culture in the middle ages enjoyed wine only after finishing the meal. In the chapter on alcohol consumption in medieval Cairo, Paulina Lewicka, from Warsaw University, wrote about drinking sessions called majlis al khmar (الخمر مجلس) literally the wine council. The second category of “The Book of Knowledge of Ingenious Mechanical Devices ” is dedicated to “Vessels and Figures Suitable for Drinking Sessions.” In all ten chapter, every chapter covers one device there is not a single meal. It seems that in the palace in Diyarbakir the meals were separated from drinking parties. This makes the question which wine goes with a fish irrelevant. It is still interesting to know what kind of wine they’re drinking? In the chapter of the automaton of the slave holding a fish and a goblet, it  “clarified wine” (sharab murawwaq) is mentioned. “Clarification” is the processes by which insoluble matter, like dead yeast cells, or various tannins, is removed before bottling, thus improving the wine quality and taste. Today this is part of the standard process, and this tells me very little about the actual wine they drank. In 1169 Saladin, already mentioned, became a Vizier in Cairo. He repented wine-drinking and turned from frivolity to religious life and later prohibited drinking alcoholic beverages altogether. Although the Artuqid ruler were vassals to Saladin, the prohibition was not implemented in Diyarbakir. In Cairo things were not simple either. While I was looking for information about wine drinking in this period, I found Firuzabadi’s “Wine-List.” This manuscript from the British Museum’s collections originated in 15th century Cairo. The author is careful to emphasize that he composed it in loyal support of the prohibition. By accident or intention the sub title is quite ironic: “The Cheery Companion, on the prohibition of old wine”  Then he alphabetically names 357 (!). The majority are very descriptive, ” the golden “,  “cock’s eye”, “mother of vice” and  even ‘the one which is drunken in the morning.” Even though it is difficult to know how similar or different the wines in Diyarbakir were in comparison to what we drink, we can conclude that in Diyarbakır palace they probably had a fine selection of wines.

The passing of time and great truths

Back to Primo Levi; The use of oil of Sandarac, a varnish obtained from the small cypress-like tree appears many times in the “Book of  Knowledge of Ingenious  Mechanical Devices “. The idea of using onions to evaluate the temperature of the oil was certainly within reach of al-Jazari. Perhaps he would have enjoyed the story about the onion in the recipe even after precise thermometers were used. The story of the ammonium chloride was probably incomprehensible for him. First chromium was discovered in 1797 by the French chemist Louis-Nicholas Vauquelin, and the use of chromium in the paint industry would be strange. Secondly the “detective story” is based on chemistry that he could not know; Elements, Atoms, Acids and Bases belong to the future, centuries after his time. However, I think he would sympathize with the sweet sensations felt by Primo Levi (details in the story!) when he understood that ammonium chloride the formula is the result of his own work two decades ago. He wrote:

“But formulas are holy as prayers, decree-laws, and dead languages, and not an iota in them can be changed. And so my ammonium chloride by now completely useless and a bit harmful, is religiously ground into the chromate anti-rust paint on the shores of that lake, and nobody knows why anymore.”

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Al-Jazari and Versailles Fountains

Introduction

There are six different fountains in The Book of Knowledge of Ingenious Mechanical Devices. This seems somewhat excessive. I suggested in a previous post that this can be explained by the importance of gardens in Islam. However there is another option; Throughout history, rulers asked their engineers and artists to create tangible displays of their power and wealth to impressed their allies and intimidate enemies. The Versailles fountains is an extraordinary example of ignoring cost and engineering complexity to demonstrate power and control. I will elaborate below.

Versailles Fountains, unknown photographer, Wikipedia Commons

The six Fountains of al-Jazari- How do they work?

Combined Drawing, Six Fountains, Topkapi manuscript, 1206

The technical explanation, as always, will be colored in blue, so anyone who is not interested in tilting pipes and floats can skip those bits. I wrote about the first fountain here (in Hebrew). The second fountain has an identical mechanism. The only addition is an extra delivery pipe, so when one fountain is producing a single jet the other fountain is throwing six arcs, and after an hour they switch, and the fountain that was producing a single jet is throwing six arcs and vice versa. The other fountains have a different mechanism, producing different water jets and have different timings. However, there is a lot in common:

  1. All fountains operate by the force of gravity. A house was built at some distance from the fountain and water were raised to a sufficient height to provide the jets. One of al-Jazari pumps, from category V, was probably used for this purpose. Raising the water and their transport are not included in the drawings.
  2. All fountains include a change in the water flow direction. In five out of six this is accomplished using a pipe that could tilt. This is a drawing from the book, and I added labels for clarity.

    Tilting pipe, First Fountain, Topkapi manuscript, 1206

    The water flows into the bowl welded to the transverse pipe that can be tilted (tilting pipe). The pipe is slightly more heavy on the side of tank A, and the water respectively flows into water tank A and water flows from the two right openings. Most of the water ran from the main opening to the right tank. The smaller opening has an onyx mouthpiece and will fill the tipping bucket slowly. At the right time, the tipping bucket would tip and push the tilting pipe upward, shifting the flow to tank B.

  3. All the fountains of al-Jazari had a time-based control system. Today It’s trivial to control the fountain with a microcontroller and computational power, or timing requirements are simple engineering task in comparison to any mobile phone. In the twelve century, it was a significant engineering challenge, and al-Jazari offers a variety of solutions. I have explained already the tipping buckets in the first two fountains. Fountain three and four utilize floats for the control mechanism:When the pipe is tilted to the right, the water will flow into tank A. The plug is closed so the flow to the fountain head is blocked and the tank will fill. The float is limited to the corner but it free to move up and down and will rise with the rising water. After fifteen minutes the float will lift the pipe extension, and the pipe will tilt to the left. The swing of the pipe will pull plug A’ opening the water path to the fountain head. At the same time, water will begin to flow to tank B, and the plug will seal the water flow from tank B.
  4. All six fountains of al-Jazari end with two concentric pipes and different end units. In the post about the first fountain I showed how al-Jazari generated a single jet upward, followed by six jets in a shape of arcs but there are many more options:

    Drawing of an alternative end unit. The fourth fountain, Topkapi manuscript, 1206 with my labels

The water flows in the inner pipe that is connected to tank A. The water shoots out from the inner pipe with force into the shield and descends from its perimeter like a “tent”. When the water switch to tank B, it will flow in the outer pipe generating six (in the drawing you see only two) arcs.

The Power of the ruler and the amazing story of the fountains of Versailles

I hope that my summary of the fountains shows how much thought and effort went into fountains’ engineering by al-Jazari like the Banu Musa before him. In a post (in Hebrew) about the controversy with the Banu Musa, I assumed that al-Jazari deep interest in fountains is related to the importance of gardens in Islam. However, there is another option, after all, grandiose fountains are not limited to medieval Muslim engineers.

Louis XIV built Versailles (Château de Versailles), one of the greatest achievements in French 17th century art and the emergence of the Rococo style, not only as a place of residence for the Royal family but as a part of an elaborate plan to centralize the French government and form absolute monarchy. To accomplish this, he placed the palace outside Paris, forcing the nobles to spend time at Versailles, becoming his captive guests. He has spent ridiculous sums of money in design, with gold trim and built the gardens of Versailles with many fountains. Some claim that the central political structure in France today is the result of his actions. Either way, Versailles became a source of envy and admiration from other Royal houses, and Louis XIV was the most powerful King in Europe. The story of Versailles fountains is less known.

The water challenge appeared began as more and more fountains were added. Originally water was pumped into the gardens from ponds near the château. However, there was never enough water to keep all the fountains running at the same time. Jean-Baptiste Colbert, the French Minister of Finances and notable politician, put aside the kingdom business and came up with a system by which the people who maintained the fountains would signal each other with whistles upon the approach of the king so the fountains on the route of the king will be functioning… The most ambitious project was to bring water from the river Seine. The pump was called  “Marly Machine” (machine de Marly)

Nicolas de Fer, 1720, Marly Machine

Pump power was provided by 14 water wheels, each 12 meters in diameter, driving a total of 257 pumps. The most remarkable aspect of this array was that the wheels not only drove directly connected piston pumps but also transmitted power 650 meters up a hill from there, the water was distributed by an aqueduct and pipes.

.Overstating the size of this project is impossible. It could happen only in a courtyard entirely isolated from the realities of life of the people.  A staggering workforce of 1800 employees for seven years was needed to construct the machine, more than 100,000 tons of wood, 17,000 tons of iron and 800 tons of lead.

This text, like other texts on fountains, tends to use numbers to praise and glorify the fountain. The little Prince thought it was a problem of Grown-ups :

“Grown-ups like numbers. When you tell them about a new friend, they never ask questions about what really matters. They never ask: ‘What does his voice sound like?’ ‘What games does he like best?’ ‘Does he collect butterflies?’ They ask: ‘How old is he?’ ‘How many brothers does he have?’ ‘How much does he weigh?’ ‘How much money does he have?’ Only then do they think they know him. If you tell grown-ups, ‘I saw a beautiful red brick house, with geraniums at the windows and doves at the roof…,’ they won’t be able to imagine such a house. You have to tell them, ‘I saw a house worth a thousand francs.’ Then they exclaim, ‘What a pretty house! “

I think fountains draw out of us more “numbers” than most things. If you are like the Little Prince and numbers are not your cup of tea, you might still like to know that the amount of water delivered to Versailles was larger than the water consumption of Paris as a whole!  The machine suffered (of course) from frequent breakdowns, required a large permanent team of technicians and engineers to maintain her, but still survived the French Revolution and worked 133 (!)  years until 1817, the year of the invention of the bicycle. I haven’t found any evidence that Louis XIV, the Sun King ever saw all this as excessive or a waste. On the contrary, he showed it proudly to his guests, including the Tsar Peter the great, who was so excited, that he built the Peterhof Palace and gardens, near the Gulf of Finland, with Versailles as a model with the largest fountain complex in the world and called one of the building after Marly

This is not the end of extravagant fountains. The following is a quote from the website of the Dubai fountains and is also excelling in using numbers. Before anything else, this is a tourist site, but behind the words, you can still hear the fountain as  a symbol of power and control:

“The Dubai Fountain is the world’s tallest performing fountain.

At over 900 ft in length – equivalent to over two football pitches – The Dubai Fountain is situated on the 30-acre Burj Lake and performs to a selection of international melodies.

The fountain has a unique design comprising five circles of varying sizes and two arcs and features powerful water nozzles that shoot water up to impressive heights equivalent to that of a 50-story building…..The fountain performs to a range of different songs from classical to contemporary Arabic and world music. When operational, the fountain has over 22,000 gallons of water in the air at any given moment.