Al Jazari and “Rav-Bariach”(Multi-Lock)

” If I have seen further than others, it is by standing upon the shoulders of giants.” Isaac Newton in a letter to Robert Hooke, 1676

Introduction

From “Rav-Bariach” web page (in Hebrew) I copied the following paragraph:

“In 1972 an upset customer came into the locks shop where Abraham Bachri used to work and requested to install four locks on her door to provide her lost sense of security following a burglary she experienced. This innocent request sparked the imagination of Abraham, who along with his friend Moshe Dolev, developed a multi-lock that was installed in the center of the door, first a wooden door and later with steel core.”

I have no reason to suspect that either man knew the “four bolt” lock designed by al-Jazari, but the lovely similarity made me think about inventions and “reinventions.” The question of who invented the telephone or the light bulb, to name famous cases, generally has legal and economic implications. I am more interested in the human spirit, and this will be the topic of this post.

Drawing of the locking mechanism of the four bolts, Topkapi manuscript, 1206

How does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in bolts or locking mechanism can skip those bits. There are four bolts made from wood or iron, on the back of a door, in all four directions. One closes to the right, one to the left, another upwards and another downwards. Each bolt is notched with “, triangular teeth “sawtooth”  facing the locking mechanism, in the center, with a key lock:

Drawing of the notched bolt, Topkapi manuscript, 1206.

The locking wheel has teeth match to the bolts, but it only rotates when the key is inserted into the lock, then each bolt locks the door on one of the sides (top, bottom, left and right). The following image compares the original lock “Rav Bariach ” and the reconstruction of the lock of al-Jazari from the Museum of The History of Science and Technology in Islam in Istanbul:

You can see two locks with four bolts on four sides with a central locking system and a single key. This is a short video of the reconstruction of al-Jazari lock

A little bit of trigonometry

During my military service, I met a guy, from a religious Kibbutz, called Yakir Katz. (It was almost 40 years, and I could be confused with the details) He told me, bursting with laughter, that his father, who worked in the Kibbutz workshop, came home full of excitement and said he discovered a relation between the two legs of a right angle triangle depends only on the angle. Yakir explained to his father that this is the tangent (marked as tan or tg), and  it is a basic trigonometric function that every high school student learns:

tan(alpha)=a/b

I remember us arguing vigorously because I thought that the “rediscovery” of the Tangent is not ridiculous at all but really a reason for astonishment and even admiration to a man whose life circumstances allowed him who only limited education (I think eight years) and he had to go to work at a young age.

Trigonometry (from Greek τρίγωνον “triangle” + μέτρον “measurement”) is the study of triangles and the relationships involving lengths and angles of triangles.These relationships are expressed using the trigonometric functions, of which the most used are the Sine, Cosine and the Tangent already mentioned. Hipparchus of Nicaea, astronomer, geographer and Hellenistic mathematician is known as “the father of trigonometry,” was the first to create trigonometry tables. For young people who never saw a trigonometry table this is how we used to find Tangent or Sine values before calculator become available:

Sine values from the trigonometry tables

His other famous achievements in Astronomy include setting the length of the solar year with an error of about 6 min per year, inventing a system of coordinates to position stars and ranked stars according to their brightness further developed by Ptolemy. That system by Ptolemy is effectively still in use today.

Shoulders of giants

The metaphor of dwarfs standing on the shoulders of giants (Latin: Nanos gigantum humeris insidente) is attributed to Bernard of Chartres, a twelve-century French scholar. The metaphor meaning is that science and technology advance based on previous knowledge. Its most familiar expression is by Isaac Newton (the motto of this post) “If I have seen further it is by standing on the shoulders of Giants.”

Newton’s quote appears in a letter to Robert Hooke one of the greatest experimental scientists of the 17th century, a polymath, architect, astronomer, philosopher, and the author of Micrographia the first scientific best-seller. Some people believe that this comment was an insult to Hooke, who was a hunchbacked due to a severe Kyphosis, following the criticism of Hooke on the Newtonian optics and the bitter feud between the two men who accompanied them until the death of Hooke in 1703. But the original letter is three years early to the conflict and Newton write with high esteem to Hooke. From the letter, it seems that the famous quote reflects the genuine perception of Newton of his achievements and science in general. It is interesting to note, in this context, that in various places al-Jazari indicates his debt to giants from the past.

Obviously, I don’t recommend anyone to “reinvent” something, and it is far superior to lean on “the shoulders of giants.” But is there a significant difference between the human achievement of Yakir’s father and Hipparchus of Nicaea? As far as both are concerned trigonometry as a mathematical tool didn’t exist, and both developed what was necessary from scratch.

It’s not really connected, but I couldn’t resist. The picture of dwarfs standing on the shoulders of giants reminded me the story of Orion, son of Poseidon. He was enormous in stature and the most handsome of the earthborn. He courted Merope, daughter of Oenopion. Oenopion was unhappy with the giant lover, gave him wine to drink and stabbed out Orion’s eyes. Orion stumbled to the workshop of Hephaestus. Hephaestus told his servant, Cedalion, to guide Orion to the uttermost East where Helios, the Sun, healed him.

Greek mythology: A manuscript from the 15 century. The blind giant Orion is carrying the boy Cedalion on his shoulders to act as the giant’s eyes.

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.”

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.

 

The automaton who drinks the king’s leaving

Introduction

In medieval Islam, the court comprised, in addition to functional appointees, a large number of people with diversified talents from litterateurs to astrologers, poets, singers, and jesters. From this group of people emerged -the boon companions, in Arabic نديم nadim – a class by themselves. They were selected from the best talents to befriend the ruler and were given a permanent position which carried great prestige and influence. Al- Jazari made a boon companion from jointed copper. He holds a goblet in his right hand and a waterlily in his left.

Category II chapter 6 Fig 94 p115 Topkapi

Fig 1, The Boon-Companion, Topkapi manuscript, 1206

Al-Jazari wrote that “It was one of the customs of the kings to leave some [of the wine] in the goblet and this was drunk by a boon-companion designated for that duty” The automaton is replacing this boon-companion.

I read quite a lot of material about the boon companion in recent weeks, some of it you will find below, but I haven’t found an explanation why someone should drink the King’s leaving? Tasting the wine before the king makes sense, because of the fear of assassins but why drink leftovers? Explanation will be gladly accepted.

After the king drinks, the steward takes it, pours what is left in it into the boon companion’s goblet. The automaton lifts the goblet, drinks the king’s leaving and nods his head several times. This happens every time wine is poured into the goblet. His left-hand moves, as an indication of his capacity. At some point, the head of the carousal says to someone he wishes to make fun of:

“Put him on your knee, drink, and give him [wine] to drink… He does not finish two or three goblets before [the boon companion] pours on to him all he has drunk since the beginning of the carousal, wetting his clothing. The wine flows beneath him, making him a target for laughter.”

The scene is almost taken from a wild and colorful feast in One Thousand and One Nights. This is being told incidentally in an Engineering book…

How does the boon companion work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in siphon and floats can skip those bits. This is a drawing from the book, and I added labels for clarity.

Category II Chapter 6 p 117 fig 97 Topkapi_wLables_en

Fig 2, The Boon-Companion mechanism with my labels, Topkapi manuscript, 1206

The automaton is in the form of a five-year-old boy( I don’t think the illustrator read the book, as the figure looks bearded and quite old). The king’s leftover wine is poured into the goblet, almost filling it, then flows through the forearm of the boon-companion into the arm tank. The tank becomes heavier, the arm will pivot, and the goblet rises to the lips of the boon-companion. His head, also on an axle, which is not shown in the drawing,  is pushed back slightly by the goblet, imitating drinking. Al-Jazari installed a siphon in the tank. We came across one in the post about the Peacock basin and the magic of automatons(only in Hebrew, will be translated soon). The siphon is a tube in an inverted ‘U’ shape, which causes a liquid to flow upward, with no pump, but powered by the clever use of gravity:

siphon

Fig 3, A siphon

Ancient Egypt paintings indicate the using of siphons in the wine industry as early as 1500 BC.There is physical evidence for the use of siphon by Greek engineers in Pergamon the third century BC.

siphon Egypt

Fig 4. Ancient Egyptian paintings from the Tomb of Kynebu, Thebes, 1450 BC.

Hero of Alexandria, who I mentioned before, wrote extensively about siphons in his treatise Pneumatica, and the Banu Musa brothers, who were also discussed, invented the double-concentric siphon. So the use of siphon by al-Jazari is not new, only an elegant solution for the boon-companion automaton. Atmospheric pressure pushes the liquid up the tube providing the siphon is filled with water or wine in our case. In the automaton of al-Jazari, this is achieved by the pivoting of the arm. Then the wine runs from the end of the siphon into the main tank. The arm tank becomes lighter and rises while the arm and the goblet sink. The head of the boon-companion moves forward and oscillates several times. As the wine is rising in the main tank, the float rises with it releasing rope through the two pulleys and the left hand, holding the waterlily sinks. When The float has no room to rise, the waterlily touches the thigh of the boon-companion, indicating the master of the feast that it is time for buffoonery. If the boon-companion drinks an additional glass or two, the wine will rise to the bend in the siphon and wet the poor holder.

The Boon- Companion and  the Courtyard Culture in Diyarbakir

The gap between the Islamic history and culture, as I (a secular Jew, living in Tel Aviv, looking at Islam from the outside through meetings with students, colleagues, press, and television) understand them to the life as shown in al-Jazari’s book is huge. Contemporary Islam is fully committed to the Sharia law (شريعة), somewhat similar to the Jewish orthodoxy, far away from the feasts described in the medieval literature and poetry of the golden age of the Abbasid caliphate in Baghdad but also of the small principality in Diyarbakir.

The importance of boon-companionship as an institution is evident from the many references by kings, court stenographer, historians and even cookbook writer.

I will bring just three examples of this wealth of information :

  1. The ‘Kitāb al-Fihrist (كتاب الفهرست) by Ibn al-Nadim, a bookseller, and a boon companion himself (note his name!)  in the tenth century, Baghdad. Is an  Index of all books written in Arabic in his time. The term catalog may be misleading, the author described the lives of thousands of authors, listing all the titles of their books and evaluating their merits. He also dealt with the religions, customs of his time and its scientific achievements. It is actually an outstanding cultural encyclopedia. It is interesting to note that a chapter is dedicated to “boon-companions, table-companions, literary men, singers, slaptakers, buffoons, and comedians.”

 An example from the Fihrist is Abu al-Anbas al-Saymarī.  He was a high ranking judge and close associate of ninth-century caliphs in Baghdad.

“Although he was one of the jesters and clowns, he was also a man of letters, familiar with the stars, about which he wrote a book [actually tow manuscripts remained] I have observed that it was praised by the leading astrologers. [Caliph] al-Mutawakkil included him in the group of his court companions, giving him special attention.

Among books that the Fihrist lists by al-Anbas are:

  • Aids to Digestion and Treacles
  • Refutation of Abu Mikhail al-Saydanani in Connection with Alchemy
  • Interpretation of Dreams
  • Rare Anecdotes about Pimps
  • Superiority of the Rectum over the Mouth
  • The Surnames of Animals
  1. Ibn Sayyar of Baghdad was the author of a tenth-century cookbook, Kitab al-Ṭabīḫ ( كتاب الطبيخ‎, meaning The Book of Dishes). This is the earliest known Arabic cookbook. It contains over 600 recipes. The final pages are guidelines for drinking parties, especially in the presence of the king. There is a very detailed description of what is expected from the boon-companion. This is a brief excerpt from the book:

 “The nadim [ boon companion] who drinks with the king must occupy the place that has been assigned to him, without seeking to put himself in a higher or lower position, he must not lie down but rather hold himself in an upright position… he must not yawn… nor persist in an argument under the effect of  drink because whoever behaves in this way is boorish.”

  1. Al-Mas‘udi (Arabic ابو الحسن علي المسعودي ) was a Muslim historian and geographer. He is known for his book Meadows of Gold and Mines of Gems which is a historical account in Arabic of the beginning of the world starting with Adam and Eve up to and through the late Abbasid Caliphate. Among others he describes a poetic dialogue between a secretary to the caliph and a boon-companion:  :

“I am a help and you are a hindrance;

I am for eagerness and you are for jest;

I am for hard work and you are for leisure;

I am for war and you are for peace.”

To which the nadim retorted:

“I am for well-being and you are for trouble;

I am for companionship and you are for service;

when you get up I sit down;

and when you are angry I am friendly.

I am called nadim [literally ‘he who regrets’ ]

because of the chagrin felt at my departure.”

The Perpetual Flute and al-Jazari’s Library

Introduction

The Book of Knowledge of Ingenious Mechanical Devices contains quite a few musical automatons. Some of them such as the musical boat we have already met in previous posts, others such as the world’s first drum machine, we will meet in a future post. The fourth category deals mainly with fountains, but there are also four perpetual flutes, which use the flow of water to compress the air through a flute thus replacing the flautist. Al-Jazari specified three sources for his works, Apollonius the Indian carpenter, a drawing from an unknown source, and a work by the eminent inventor, Hibat Alla b.al Husayn al Astrurlabi. It made me wonder about his library.

Figure 1 The perpetual flute, scattered pages (copy from 1315) (Metropolitan Museum, New York)

How does the flute work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in the tilting pipes and floats can skip those bits. This is a drawing from the book, and I added labels for clarity.

Figure 2 The perpetual flute (1206). Topkapi manuscript (with added labels)

There is a constant water supply to the perpetual flute. The water flows into the bowl welded to a transverse pipe that can be tilted (tilting pipe). The pipe is slightly heavier on the side of tank A, and the water thus flows into that tank. The air is pushed out, and the only way is through flute A, so a sound is heard. Although it is called a ‘flute’, it is more like a whistle as the pitch cannot be changed, and there is no parallel for different fingering producing different notes. At the same time, plug B is pulled out, thus emptying tank B. The water will continue to flow into tank A and float A will rise with it. At some point, float  A will push the tilting pipe upward, and shift the water flow to tank B. The water will rise in tank B  and the only route for the air will be through flute B. This process repeats itself as long as the waters supply continues.

 

The literature survey and al-Jazari’s Library

Any research or technology development project starts with a literature survey. Students, especially in the early stages of their training in science or technology, feel that the survey is tedious, and perhaps a formality and not helpful. But in time they will learn that the survey is needed to map the current information available and is essential from the very early stages of understanding the theory and developing the methodology until the final stage of writing the paper, the patent request or the research report. Modern scientific disciplines emerged centuries after al-Jazari. I do not know if literature surveys were the norm in early scientific papers. Was al-Jazari a precursor in using them or is he following a known path? In previous posts, we saw references, and a critique of the work of Archimedes and the Banu Musa. But in this chapter three resources are mentioned:

  • “I came across a well-known paper by Apollonius, the Indian carpenter: he made a wheel which turns slowly and opens water outlets…”
  • “I also examined another old instrument, about which I found no written report, but a drawing. In this, the flute is like a nay having eight holes”.
  • “I [also] examined a paper written in Baghdad in year 517 A.H. by the eminent inventor Hibat Allah al-Husayn al-Asturlibl, in which he makes a real innovation….”

Figure 3 Treatise on the Design and Construction of a Hydraulic Flute Playing Machine. Attributed to ‘Apollonius the Carpenter and Geometer’ (sixteenth century) (British Library: Oriental Manuscripts)

In the next post about the perpetual flute with two tipping buckets, I hope to elaborate on these early works and what survived the hundreds of years that passed. However, the fact that al-Jazari had three different sources for the perpetual flute made me think that he had quite an impressive library. Was this the Diyarbakir Palace Library? In the library, were there shelves dedicated to engineering and technology? Who else was reading these books? Maybe these books were in his workshop? Manuscripts were done by hand and required a lot of careful writing and drawing. The price of a manuscript must have been very high, so how would it have been possible? I wish we had answers to all these questions, but we do not. However, some more general information is available.

 

Manuscripts and libraries in the golden age of Islam

Paper was invented in ancient China. Legend says that two Chinese prisoners captured by the Abbasid Empire after the victory in the Battle of Talas (Kyrgyzstan) in 751, revealed the secrets of paper making. I do not know if this true or not, but there is enough historical evidence for a dramatic paper revolution in the Muslim world in the ninth and the tenth century. In Baghdad, the Chinese art of paper making was improved and mechanized. Linen and rags replaced the traditional mulberry tree bark as raw material. The use of water-powered or animal-powered mills for preparing the pulp helped in transforming paper-making into an industry. The Muslims also introduced the use of trip hammers. The producers in Baghdad and Syria became the main suppliers of paper to Europe. Paper became cheaper and of better quality. The Islamic culture in the Middle Ages, which originally had higher literacy rates, certainly in comparison to Europe, was becoming a leader in sophisticated book production processes, flourishing book markets and rich libraries. All this resulted in a dramatic increase in the availability of books and their accessibility to various segments of the population.

The adoption and industrialization of paper-making is the opposite of the Ottoman Empire’s refusal to embrace Gutenberg’s printing press revolution. It requires another post, but until the eighteenth century, the Turks allowed only non-Muslims, especially Jews, to print. Two revolutions: paper was adopted and the printing press was rejected, both extreme examples of how technology affects culture and society and how seemingly technological decisions can change society.

We know quite a lot about libraries in the Muslim world. The first of which is the House of Wisdom ((بيت الحكمة‎;) founded by Harun al-Rashid, the fifth Abbasid Caliph in Baghdad and the House of Knowledge ((دار العلم) established by Al-Hakim bi-Amr Allah, sixth Fatimid Caliph in Cairo. The two libraries were centers of Islamic learning of the Qur’an and Hadith, philosophy and astronomy. The Fatimid historian Al-Musabbihi wrote:

into this house, they brought all the books that [the Caliph] ordered to be brought there, that is, all the manuscripts in all the domains of science and culture, to an extent to which they had never been brought together for a prince. He allowed access to all this to people from all walks of life, whether they wanted to read books or dip into them… He granted substantial salaries to all those who were appointed by him there to do service, jurists and others… He also donated what people need: ink, writing reeds, paper, and inkstands”.

Figure 4 Scholars in the Library in Baghdad, illustration by Al-Wasiti (1237)

There are fantastic stories about the size and richness of these libraries. For example, it is said that during the Mongol siege of Baghdad in 1258 AD, the House of Wisdom was destroyed. The books were thrown into the Tigris River in such quantities that the river was black with the ink. Nasir al-Din al-Tusi rescued about 400,000 manuscripts which he took to Maragheh before the siege. The closest I came to Al-Jazari’s library was a short remark in the diaries of Carl Süssheim. He was an Islamic historian and orientalist. In his diaries, he tells a story about Emiri Efendi who sold him precious manuscripts. According to Emiri Efendi, Saladin, founder of the Ayyubid dynasty who defeated the Crusaders at the decisive Battle of Karney Hattin, “scattered the library in Diyarbakir which contained millions of volumes”. I could not find any other reference to support this. All this information makes manuscripts more accessible than I originally thought, but I still wonder what al-Jazari’s library looked like.