automaton

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The Musical Boat for a Drinking Party

Introduction

The Musical Boat is the fourth of ten automata (mechanical dolls) and vessels that were designed to amuse guests at drinking parties at the King Court in Diyarbakir. On the boat deck seat the king, his and weapon-bearer, a slave holding a jug and goblet, as if serving drinks. Below there is a group of boon-companions and four slave girls, a flute-player, a harpist and two tambourine-players. The King and his court are static, papier-mâché sculptures. The musicians are made from jointed copper, and their arm can move. Professor Noel Sharkey sees in the unique mechanism al-Jazari designed for the drummer the world’s first programmable robot. More on this topic, below.

The musical boat, Topkapi manuscript, 1206

How does the boat work?

The boat moves gently on the surface of the pool at the Palace. Once every half hour, without any external intervention, a performance begins; The flutist would play the flute, the drummer would beat the tambourine, and the harpist plucks the copper strings. Here is a short mute (unfortunately) video of a model of the musical boat. After approx. Fifty seconds you can see the mechanism in action.

 

The technical explanation, as always, will be colored in blue, so anyone who is not interested in tipping buckets or early camshafts can skip those bits. The diagram below is the original drawing of al-Jazari with my captions:

The slave girls (musicians) are sitting above a water reservoir. The tank empties slowly into the tipping bucket. When the tipping-bucket has filled, after about half an hour, it discharges its water onto the scoops wheel, turning the wheel on its axle. The pegs on the axle rotate as well moving the rods which are connected to the slave-girls’ hands, moving them up and down. This creates the motion of the harpist plucking or the drum beating. The harpist has a three peg system for one hand, and the other hand is operated by one peg only. The rods are an early version of a camshaft and convert the circular motion of the axle to the linear movement of the musicians’ hands. The spacing between them generates different patterns of drumming or harp music. The water flows down into the pipe which is connected to the air vessel, forcing air through the whistle. This is the source of the “flute” sound.

Qiyan – Musician slave girls

The drawings in the facsimile edition were not done by al-Jazari. Donald Hill, The book translator, and annotator, detailed eleven manuscripts all over the world. The earliest copy, now in Topkapi Library (MS 3472) was completed by Muhammad Ibn Yusuf Ibn Uthman alHisenkafi in April 1206 and is the source of a facsimile. When a scribe finished copying a manuscript, a task that lasted weeks or even months, he would add a colophon, brief statement containing information about the publication such as information about the scribe and the manuscript. This is how we know that this copy was completed in 1206, the year al-Jazari died. We can assume that this copy was prepared from the original book, and the drawings are quite similar to the original. This is interesting because of the affinity between the Clothing of the boon- companions and the slave girls. The boon companions and the girls are all wearing qaba, a robe with sleeves, at mid-calf –between the knee and ankle that has a diagonal fastening of one side over the other. The color scheme is also identical. This made me think of them as “male musicians” Although the text is very clear about slave girls

Qiyān (Arabic: قِيان‎, ) was a social class of slave women, trained as entertainers, which existed in the pre-modern Islamic world. Qiyān is often rendered in English as ‘singing slave girls,’ but this translation does not reflect the fact that qiyān were skilled entertainers whose training extended well beyond singing, including composing music and verse, reciting historical or literary anecdotes, calligraphy, or shadow-puppetry and more. Qiyān were important in performing and distributing the works of the composers of the period in the Palaces of Islam from the eighth to the thirteenth century. They received broad education from an early age, including science, philosophy, and art. Beyond being gifted poets, dancers, or musicians, they were supposed to be courtesan with high conversational skills. There’s quite a bit of information about Qiyan in Baghdad, the Abbasid capital. In these years Bagdad was a cosmopolitan city and the center of science, culture, and philosophy. The musical slaves came from different cultural backgrounds. We know of Qiyān from all over the world, from Rome to India. They were bought in for outrageous sums of money, but the slavery is somewhat confusing, and those released remained in palaces in the same role? You can’t compare the tiny principality of the Artuqid with the Abbasid caliphate in Baghdad, but the presence of the Qiyan in Diyarbakir is another indication of the cultural flourishing in line with the original architecture  [Hebrew] and the initiative to write the ” Book of Knowledge of Ingenious Mechanical Devices.”

Musical robot

The word ‘robot’ was first used by Czech writer Karel Čapek in his 1921 play R.U.R -Rossum’s Universal Robots. The word ‘robot’ itself was not new, and come from Slavic language robota, meaning servitude. Oxford dictionary definition, “a machine capable of complex operations automatically, especially with programmable computer” is problematic, if only because my car is capable of a complex series of actions automatically, it has a large number of programmable electronics, and it is not a robot by any definition. In literature and science fiction movies, we use “robot” for an android, a machine resembling a human being and able to replicate certain human movements and functions.

Čapek’s book was written in 1921, long before Ted Hoff invented the microprocessor. When we talk about ancient robots and the automata al-Jazari built and ask ourselves if they should be considered as the predecessors of robotics, the questions should be two:

  1. Was it possible to program? Or in other words, do they have the ability to do different actions by design?
  2. Do they have autonomy? The ability to decide what to do and how to do it?

The question of “what was the first device that could be programmed?” is more theoretical than practical, but the musical boat is a leading candidate. Professor Noel Sharkey of Sheffield University built a model of a single drummer from the musical boat to illustrate how it can be “programmed.”  Beneath the ‘drummer’ was a rotating shaft with pegs on it. As these pegs rotated they pull on a lever that raised the drummer’s arm and then it dropped to hit the drum. The placement of the pegs entirely controlled the rhythm and timing of the drum beats. The purpose of the model was to demonstrate that one can play different beats using different peg patterns by changing the peg locations and spacing.

Did al-Jazari actually “program” the musical boat? We will never know. He probably used this method during the design to get the rhythm he liked. Whether it was used or not, the musical boat shows the possibility of “programming.” The question of autonomy will have to wait eight centuries until engineers would have sensors and computerized systems.  For those who want to expand, I attach a short (about ten minutes) film from the history channel. It introduces the subject of Robotics and the contribution of al-Jazari and other ancient robots. For some reason, they turned al-Jazari into a Persian?

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The Drummers’ Clock and Musical Robots

Introduction

The Drummers Clock is a water clock and probably one of the first drum machines and musical robot ancestor. It features five mechanical drummers: two cymbal players, two drummers with a drum slung over their shoulders, and a drummer sitting in front of two kettle drums. Despite significant advances in robotics and AI- Artificial Intelligence, musical robots fall short compared to human musicians; their music lacks subtleties and is “mechanical.” The simplicity of the drum machine, in contrast to a robot violinist, helps to focus on the real issue. This post moves between explanations of the drummers’ clock and thoughts on the difficulties in creating a “musical” musical robot.

The Drummers’ Clock, a dispersed copy, 1315

How does it work?

This is a simple version of the Castle clock with fewer mechanisms to display the time, and those that remained are simpler. The large components: The water tank, float, and flow controller are identical to the Castle clock and the “Time cart” is very similar, a little like a cheap version of a mobile phone. Al-Jazari does not explain them again but refers the reader to the first chapter (the Castle clock). I also turn directly to musicians. Al-Jazari writes:

 “When an hour has passed the musicians (نوبة – nūbah, a musical genre found in the North African, it has its origins in Arabo-Andalusian music.) perform with a clamorous sound which is heard from afar.”

The technical explanation, as always, will be colored in blue, so anyone who is not interested in tipping buckets or scoops wheels can skip those bits. The diagram below is the original drawing of al-Jazari with my captions.

The water flows on the scoop wheel once an hour. This is a large clock, and every time about eight liters of water flows. It is turning the scoop wheel on its axle so that the pegs move the rod which is connected by a copper chain to the slave-girls’ hands. The pegs are an early version of a camshaft and convert circular motion to linear movement. The number of pegs and the intervals between them create different patterns of drumming. The copper strip goes through the hollow wooden body of the musician, and when pulled it goes up and later falls to hit the drum. The pegs are organized in a way that is characteristic of the work of al-Jazari, two adjacent pegs, and a third peg apart. The result is two relatively fast beats, and a third after a pause. There are also two trumpet players, but they are only “decor accessories.” The sound of trumpets is produced separately by the water pouring into an air vessel and compressing the air out through the pipe with a whistle.  Al-Jazari used this in many devices, including the Perpetual Flute.

Robotics and the student’s disappointment

Robotics is an enjoyable and sometimes exciting way to teach and learn science and technology. This is true for excellent students and students with difficulties in mathematics and science. Most of the students gladly take upon themselves robotics problems, research a topic, and build a robot using original thinking and their ideas. I taught robotics in different settings: in elementary school Gavrieli, in middle school Branco Weiss and at the Davidson Institute of science education. I found it a creative learning experience in all the years I taught. Beyond the programming tools, mechanical engineering, electronics, and sensors, it teaches children to confront and overcome obstacles, builds confidence and self-esteem, and gives inspiration to science and technology. As a part of the introduction, I would present a wide range of robots, including a robot that plays the violin:

In almost every class I taught, students (happy and enthusiastic) were complaining that the robot’s performance is “mechanical” or “robotic” as a weakness. Violin has a wealth of nuances in how the violinist produces the violin sound (Timbre). This results from many choices, such as which string to use, the pressure of the bow, the point of contact, the bowing speed, to use the whole bow or only partially. All these choices reflect the musical understanding of the violinist and will echo emotionally with the listener. The Musical robot in the movie is programmed so that it “knows” to play the notes, but it has no musical understanding at all. The concept of an artistic interpretation is foreign to him. The drum machine is much simpler in comparison to the violin and will facilitate the discussion.

Musical robots and music

The drummer’s choice includes “merely” the question of the drums selection and the beating template. In terms of the drum machine of al-Jazari, this is the arrangement of the pegs for each drum and possibly changing the length to affect the volume. Al-Jazari made these decisions during “programming” or the design phase, but we can easily think of a modern drumming robot with all the parameters free to change in real-time. This will allow changing hand techniques and evolving drum beat patterns but will not progress us even one step toward musical interpretation.

This is a nontrivial challenge for robot builders. Robots in science fiction literature and toward the end of the 20th century are machines that can replicate human action, especially when it is repetitive. When Karel Čapek coined the word “robot” in the play R.U.R (Rossum’s Universal Robots), the idea was to replace humans when the work was tedious, difficult, or even dangerous. Prominent examples are the welding robots in the automotive industry or the Police Bomb Disposal Robot. In recent years, there has been a shift in direction, and a lot of research has been done on Artificial Intelligence (AI). There are exceptional results in various fields, including robotics stock traders, diagnostic medical robots, and precise surgery robots. What was considered thirty years ago insurmountable, like software playing chess or go (a Japanese board game) is a reality. Chess software like Komodo can beat any human grandmaster. The contribution of AI to music (AIM- Artificial Intelligence Music) is more modest and limited, at this time, to conferences and academia, and no robot can be matched to a human musician. People are not jamming to concerts to listen to musical robots. AIM is a broad field and includes many topics, some of which are relatively simple to understand, Like:

  • Methods to produce music using musical robots
  • Storage of digital music

Some are more complex, but still approachable:

  • Symbolic representations of music – how to represent music beyond the note, including “human touch” and interaction between musicians.
  • Human-computer interaction-music – how can a computer respond to music, including jazz improvisation.

Some are borderline science fiction:

  • Cognition Computational music – the idea is to teach the computer what is needed for music playing or composition. Moreover, to treat this as a process and do the same learning that does a composer/performer.

As someone who likes robots and automatons, maybe like al-Jazari at his time, I’m surprised by the pleasure I get from reading about the difficulties of the AIM community and the human abilities which are so hard to imitate. Despite what I wrote, I would like you to see the film below: I don’t know how it was done and what part is human, and what part is AIM, but it is certainly fun to watch and listen to!

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The basin of the Peacock and the magic of automata

Introduction

The basin of the peacock is an automatic basin for the ritual ablution- Wuḍū (وضوء). A servant brings the basin and positions it so that the beak of the peacock is facing the master. The servant pulls a hidden lever in the tail of the peacock, and water begins to flow. Then the left door opens, and mechanical slave emerges holding soap. Toward the end of the washing, the right door opens, and another mechanical slave emerges, this time, holding a towel, to dry the master’s hands. The automata are important to the history of technology. Methods invented to refine automata laid the basis for modern technology, but I hope in this post to talk about the source of the magic of automata.

Basin of the peacock, Topkapi manuscript, 1206

How Does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in siphons or automaton mechanism can skip those bits.

The hollow Peacock is made of copper, large enough to contain the water needed for the purification ceremony. The arched neck is a siphon. A siphon is a tube in an inverted ‘U’ shape, which causes a liquid to flow upward, above the surface of a reservoir, with no pump, but powered by the pull of gravity. The siphon will work while the water in the peacock’s body would rise above the bend in the peacock neck. The peacock’s tail, which is spread out, is divided into two volumes. The bottom part is connected to the body of the peacock. The top is separated with a conical plug. This plug is connected by a curved lever which reaches the cover of the tail. At first, the servant fills the water when the plug is open, thus filling the body of the peacock and the lower half of the tail then he pushes the plug. At this stage, the water level is below the bend in the peacock’s, so nothing happens. With the plug in place, he fills the top half of the peacock’s tail and brings the basin to the king. Now the servant pulls the plug and connects all the Peacock parts. The water came down and rise over the bend of the Peacock neck, and the ritual ablution begins.

Al-Jazari and  Donald Hill settled for a side drawing, but my love M. insisted that it’s hard to understand the operation of the automaton without a frontal drawing. So I expanded the drawing:

When pouring water into the basin, the water flows through a hole in the floor into the lower chamber, and the float goes up until it pushes the mechanical slave holding the soap, causing him to move forward and open the left door and thus “offer” the soap to the king. The float doesn’t continue to rise because its movement is limited by the ceiling of the lower chamber. The water continues to rise to the upper chamber, so the second float begins to rise. His rod is shorter and triggers the second mechanical slave just before the water end. When the second slave moves forward, it opens the right door and offers a towel.

 

Automaton  (self-operating machine) magic

Automaton (plural automata) were not invented by al-Jazari. We know of automata in ancient Greece (Greek: αὐτόματον “acting of one’s own will”). The automata were used in temples and as accessories in the Greek theatre.  The first engineering text that I am aware of is by Hero of Alexandria, a mathematician, engineer, and scientist from the 1st century AD. “Automatopoietica” (αυτoματoπoιητικ ‘ ης) usually translated “on making automatons.” It is reasonable to assume that Hero knew of Aristotle’s “Poetics,” the earliest surviving work focusing on literary theory, in which Aristotle examine the principles behind epic poetry, comedy, and mainly tragedy. We can expand (?)  Poetics as the artistic elements which compose any art form and in our case, the art of automata. Today when we say poetic, we mean an emotional, leary style of expression. I don’t know if this was true in Alexandria, the book is a description of machines that perform “magic” with mechanics or pneumatics, such as automatic door opening in the shrine or statues that pours wine.

Al-Jazari developed and perfected the world of automata. He was the first to employ the camshaft as part of his automata, see the Castel Water Clock or the  Musical Boat [in Hebrew]. He also expanded the use of water flow, smart use of gears, buoys and balancing weights built a long list of automatons, some I already covered, and some I would translate from Hebrew in the near future.

The 18th century was the golden age of automatons. Most of them rely on the camshaft quite similar to the work by al-Jazari. It’s hard to choose between the many exotic examples. I can’t ignore the “Digesting Duck”  (Canard Digérateur) built by Jacques de Vaucanson. The Duck was the size of a living duck and was covered in perforated gold-plated copper to allow a view of the inside workings. It moved like a duck, wiggling its beak in the water, quacking, and most famously though, it could eat pellets offered to it, and then poop them. De Vaucanson claimed that duck contained a small “chemical laboratory” capable of breaking down the wheat grain. In the 19th century, it was found that Vaucanson had faked the mechanism, and the Duck’s poop consisted of pre-prepared breadcrumb pellets, dyed green.

An American artist’s (mistaken) drawing of the Digesting Duck.

I particularly like the automaton of Maillardet, also known (by error) as “Maelzel’s Juvenile Artist.” This is an automaton that can draw four different drawings and write in calligraphy three poems which, among other things, revealed the true creator, Maillardet, in contrast to its wrong reference to Maelzel. The full story appears in this video:

It is impossible to ignore that the eighteenth century is the age Romanticism (also known as the Romantic era), an artistic, literary, musical and intellectual movement originated in Europe. For example in a Hoffman story “The Nutcracker and the Mouse King” Mr. Drosselmeyer, who is a clockmaker and inventor, made a splendid gift for the children: a clockwork castle with mechanical people moving about. Also Olympia, in Der Sandmann (The Sand-man), the life-size mechanical doll with which Nathanael falls disastrously in love. Nili Mirsky in the epilog to “The Golden Pot and other stories “writes about chronic dualism: In the day a strict Prussian judge and in the night a romantic poet or the tension between the occult world and what is exposed in his stories. I suggest adding the tension between the mechanical doll and living humans.

The methods invented to refine mechanical dolls laid the basis for modern technologies, not only for robotics. For example, Edmund Cartwright patented the power loom in 1784, key development in the industrialization of weaving after a visit to “The Turk,” a mechanical doll who played chess and then proved to be a hoax. The mechanical part was real, but there was a concealed man who computed the chess moves. Cartwright wrote: “it is more difficult to construct a machine that shall weave than one which shall make all the variety of moves required in that complicated game?”. Thomas Edison incorporated the camshaft of al-Jazari or Maillardet with the music box and created the phonograph, the first device that allowed recording of music or voices. In general, there are many more examples of a drift of the technology from the “useless” world of automatons to the “practical” world, but I want to talk about the source of the magic.

The automaton is a mechanical doll who moves around and does things that are reserved only to living beings. I don’t think the automata maker confused themselves with the all-mighty creator. There is no mysticism or black magic in mechanical dolls, but there is small magic or amazement in the gap between the mechanical system and human behavior.  Allegedly this magic should disappear in the modern world. Drawing and writing poems are relatively simple tasks for a LEGO robot, which is only a toy. At MIT-Laboratory researcher investigate energy-efficiency in legged robots and created a mechanical “Cheetah” that goes far beyond any dream of makers in previous centuries. I am the last person who wants to reduce the wonder from the Cheetah but the kids watching the contemporary robot do not have the amazed face of the kids watching  “Maelzel’s Juvenile Artist.”  was the charm preserved? Why? I think magic is different. The observer in the thirteenth century and the eighteenth-century lived-in a world with a lot less technology and understood the world around him in a way that we lost. We live in a world saturated with technology and used to not understand most of it, even if we have a technological education. The cell phone in our hands is a powerful computer. Hundreds of engineers from various disciplines, electrical engineer, material engineers, chemists, and a solid-state physicist were needed to produce the microprocessor alone. I doubt that there is one person in Apple or Samsung that knows all the details of the microprocessor, and this is before we even discuss the touch screen or the antenna. We live (well!) with our lack of understanding and content with using it without knowing “the details.” In the 18th century, and before, the automaton was a demonstration of the strength of technology. It allowed René Descartes, the famous French philosopher, mathematician, and scientist to think (fantasize?) that one day the scientific principles at the base of Humans and animals would be revealed, just like we can understand the mechanism of the automaton. This was a challenge to religion and a song of praise to science and its powers. Not every innocent observer is Descartes, but this is the root of our amazement. When we live in a technological world we don’t understand, the astonishment question is very different. Why be astonished more (or less?) by a robot or a cell phone or a game of virtual reality? The magic of the old mechanical dolls is precisely the fact that we can see the technology does its wonders, you can see the gears fit, and the reader (pushrod) moves over the camshaft. We, the eighteenth-century observer and al-Jazari, are, for one moment, in the same place of admiration.

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The Pump with the Fake Cow

Introduction

The third raising water machine described by al-Jazari is clearly an attraction in the King Palace and not a solution to irrigation problems in Diyarbakir. It’s not just the fake cow(!) made of wood, and I will elaborate on this later on, but the text speaks for itself:

“[The one described here] is beautiful to behold, with upper wheels, splendid craftsmanship, elegant shapes, and handsome design. The ropes are silken, the jars delicate and painted with various colors, as are the wheels, the cow and the disc.”

In this respect, he reinforces the concept of the palace Engineer as a “magician.” I wrote about this briefly here [in Hebrew], and I will use the third pump to expand. This design is based on the saqiya (Arabic ساقية‎‎), an ancient device for raising water that can still be seen today. In the following paragraphs, I will explain the saqiya and the similarities and differences from al-Jazari’s pump.

The third water raising device, 13th-century manuscript, SÜLEYMANIYE LIBRARY, Istanbul

How does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in Scoop wheel or Sindi wheel can skip those bits

Al-Jazari device is relatively complex, and only the top part is visible to the observer. This is the original drawing by al-Jazari with my captions:

The center of the device is a square pool with a bottom copper plate, and its sides made of marble. The water flows into the pool and down through an opening on a scoop wheel which is hidden in a chamber below the pool, not visible to the observer. The scoop wheel rotates toothed wheels that transmit the movement to a vertical axle. The axle is hidden within a copper pillar with a copper disc. A wooden cow is standing hairsbreadth above the disk, light as possible and supported by a wooden rod attached to the axle. In this way, it looks like the cow is operating the traditional saqiya. (Pictures and explanations of the saqiya will follow).Toothed wheels turn the Sindi wheel which has the jars on it. Thus raising the water and dispenses the water into the irrigation system of the Palace’s garden (not in the drawing).

It is interesting to note that al-Jazari calls the wheel of the Saqiya “Sindi wheel,” Sindh is in the western corner of South Asia, bordering the Iranian plateau in the west, today in Pakistan. So at least in his time, it was assumed that this is the “origin” of the saqiya.

 sāqīya (ساقية)‎ 

A Photograph from Spain of a Saqiya, Wikipedia

This was the most effective device for raising water used from Spain in the West to India in the East at least from Roman times to the insertion of motorized pumps. An animal (Ox or a donkey) turns a horizontal wheel, which is engaged with the vertical wheel and so causes it to turn. This causes the belt of buckets or jars to circulate and lift water from the well or the stream.  There is no knowledge about the origin of the device. Some claim it was ancient Egypt, 4th century BC, some claim Persia and al-Jazari, and his contemporaries thought Sindh. Regardless of the history, it was very common throughout the Muslim world during the middle ages.

There are many testimonies to the early saqiya here in Israel. The most ancient one in Tel Dor. A saqiya also appears in “The Picturesque Palestine” published in the early 1880s by Charles William Wilson:

The Saqiya is five times more efficient than the Shaduf, which was explained here. It can pump 10-25 cubic meters of water per hour. The unusual version of al-Jazari did not use animal power but water energy. The use of water power for pumping and industrial use, for instance, in the paper industry was known at the time of al-Jazari. The most common device was Noria(ناعورة), which consists of a large water wheel of wooden containers, as shown in the photograph below:

Three norias of Hama on the Orontes River in Syria. Originally to irrigate the City Gardens and now a tourist attraction.

Al-Jazari did not use the noria but the scoop wheel, I may write on this choice in the future. I am more intrigued by the wooden cow.

 Why a wooden cow? Or the engineer as a Magician

The wooden cow of al-Jazari contradicts all engineering logic. First of all, it has no contribution to the water raising secondly it loads the pump and reduces its efficiency. Funny that Wikipedia writer wrote:

“A manuscript by Ismail al-Jazari featured an intricate device based on a saqiya, powered in part by the pull of an ox walking on the roof of an upper-level reservoir, but also by water falling onto the spoon-shaped pallets of a water wheel placed in a lower-level reservoir.

An observer in the 12th century would not make this mistake. The dimensions of the wooden cow are not specified, but the copper disc is about two spans or ~ a half meter. The central axle that connects all the toothed wheels is 12 spans or approximately 3 meters. Even if the image isn’t to scale, it is obvious that the cow was a decoration and was not intended to mislead the observer. Why al-Jazari did this?

My love, M.  thinks it is the handicap principle. The handicap principle is a hypothesis originally proposed in 1975 by Israeli biologist Amotz Zahavi with his wife Avishag Zahavi to explain strange phenomena in nature. Their book is called “peacocks, altruism, and handicap principle” (in Hebrew). The amazing colorful peacock’s tail requires physiological resources to build and maintain, attracts the attention of predators, and hinders the peacock’s ability to escape. At the same time the heavy tail signal peahens that the peacock is very sure of himself and has an impressive set of genes, thus improving his chance to find a spouse. In some paradoxical way, the colorful tail of the Peacock also manages to deter potential predators. In the 1970s, there was broad opposition to the handicap principle because it contradicts the principles of evolution, but today it is widely accepted. Did al-Jazari want to show that an unneeded wooden cow doesn’t bother him to raise water with joy?

I prefer another explanation. We perceive engineers as professionals who analyze data to design and build machines, structures, or materials to achieve the objectives, taking into account the product requirements and limitations, including regulations, cost, safety and more. Al-Jazari was working in a different environment with far fewer limitations and no regulation at all, but his concept of engineering and his role were different. Engineers are hiding mechanisms for any number of reasons, but why Al-Jazari chose to hide the mechanism? Did the tiny wooden cow stress the lack of the usual animal in the saqiya?

I suggest that in al-Jazari’s perception, the engineer is a little bit a magician. It is certainly true for the Magic Pitcher or some of the automata, and it is true for this pump. The hidden mechanism and wooden cow are used to make the riddle more intriguing. It makes no sense to ask a magician about the efficiency of his act, and likewise, there is no sense to ask Al-Jazari why a cow? His goal was not an effective pump, but the wonder of the beholders. Elly Truitt wrote an interesting book called “Medieval Robots” about the transition of Western Europe between the perception of automata as magical to science and technology approach. Truitt tells of a 12th-century book “Chansons de geste, le Voyage de Charlemagne” (Songs of Deeds, the travels of  Charles the Great”). The story is about the visit of Charlemagne to King Hugo’s court in Constantinople. Charlemagne and his barons were astonished by an automaton of a rotating palace mimic the circular motion of the celestial sphere. When the west wind blew the Palace turn, and two copper children blew their ivory horns with heavenly music. Charles’s court thought that this automaton was so expressive that they would have believed they were actually alive. Charles and his barons were unfamiliar with the technology, lost their footing once the palace began to turn. This story is fictional. Charlemagne didn’t make this expedition to Jerusalem and didn’t stop in Constantinople on his way. It is true that there were remarkable automata in the courtyard of Byzantium in the 9th century and a people from the west who had no technological know-how, thought that magic and sorcery are involved. Al-Jazari is the magician but with no magic but hidden scoop wheel and clever use of toothed wheels.

 

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Two Scribes and Bloodletting

Introduction

This is the second basin of al-Jazari for blood-letting, “from which the quantity of blood which it holds can be ascertained.” Its mechanism is almost identical to “The Basin of Monk,” explained here with some additional background on the history of bloodletting. The main difference is in the design; two scribes are sitting on a raised platform, one writer rotates, and his pen indicates the amount of blood collected in the same manner as the monk. The other scribe has a writing pad that rises so that his pen, which does not move, indicates the amount of blood. We have plenty of information, medical and images which documented bloodletting. There is no precursor bloodletting tool before al-Jazari and all bloodletting tools after his time are simply bowls with marking. And the question is why?

The basin of the two scribes. Detached folio from a Manuscript,1315

How Does it work?

The mechanism is almost identical to the basin of Monk. The differences are so tiny, if the readers are interested in them, he or she probably do not need my mediation. Still, for the comfort of my readers, I provide my adaptation of the modern drawing by Donnell Hill, the book translator and annotator. If there are any errors, the responsibility is all mine. The technical explanation, as always, will be colored in blue, so anyone who is not interested in pulleys or balancing weight can skip those bits.

Both scribes are sitting on an elevated platform on four columns. The scribe to the left sits on the main pulley and is holding a pen which is an indication of the amount of blood collected so far. Two ropes are connected to the main pulley through the hollow columns and two small pulleys. At one end there is a float, and the other end has a balancing weight. The ropes are tight before the beginning of the bloodletting, and the pen is indicating zero. The blood goes to the basin and the drain and is collected in the container where the float is located. As a result, the float goes up and release rope through the pulley, the weight continues to pull down, and the main pulley with the scribe on it would rotate. The float is also connected to a rod with a writing pad at the end. As the amount of blood accumulates, the writing pad will rise as well. The fixed pen in the hand of the second scribe would also indicate the amount of the blood.

 

Bloodletting tools throughout history

I don’t know if there are any other medical procedure as bloodletting that got so many medical or artistic expression. This is just a small sample:

Pictures from right to left:

  • A drawing of bloodletting on a Greek vase from the fifth century BC
  • A Bowl with a scene of bloodletting from Iran, the first half of the 13th century, Islamic Art Museum, Berlin.
  • Caricature of bloodletting by James Gillray, 1804.

Pictures from right to left:

  •  A Physician is letting blood, 13 century, Aldobrandino of Siena. British Library, London.
  •  A surgeon binding up a woman’s arm after bloodletting. Oil painting by Jacob Toorenvliet, 1666.
  • Photo of bloodletting from 1860, one of three known photographs of the procedure.

In all these photos and many others, the blood is collected in a bowl.  In 1979 the Smithsonian Museum published an impressive catalog of bloodletting tools. The catalog is available online and is full of great information including an article summarizing the topic and plenty of images of bloodletting instruments; there is nothing more than a bowl with graduated marking:

Bleeding bowl with graduated markings to measure the amount of blood. Made by John Foster of London after 1740.

How do we explain al-Jazari choice?

Quite a bit of al-Jazari work relies on his predecessors. Al-Jazari himself was the first one to reference previous scholars as I showed in the Castle Clock or in The Fountain of the Two Tipping Buckets (in Hebrew). Sometimes the technological leap forward is very large, for example, water wheel pump and sometimes less significant as in all the fountains. But not only that there is no precedent to al-Jazari’s designed for measuring blood there is no ” sequel”; no one used al-Jazari ideas. It is worth mentioning his book was quite popular; there are not many manuscripts from the 12th century with 15 remaining copies and bloodletting continued for about 700 more years.

Surprising?  Maybe not. Al-Jazari solution is complicated and requires a lot of work. There is no comparison between the serial production of a ceramic bowl even in the 12th century, and fine mechanics. The materials are more expansive, the basin is made out of brass, and the scribes are made of copper. All this raised the final cost. Also, al-Jazari’s solution is much more difficult to clean and maintain, and offers only one clear advantage: it is more fun and allows the patient to track the amount of blood easily.

I have no evidence in the text, but I am convinced that al-Jazari understood the cost of material, the amount of work and the complexity of maintenance as well as I do. So why did he chose as he did? I have two proposals, and you are welcome to offer your own.

  1. I discussed this question with my young son. He said that if I were asking him in sixth grade to invent a tool that measures the amount of blood during bloodletting, he would look for a solution like this (he added a lot of limitations due to what he knew at that time) because it’s much more “cool.” Al-Jazari was an engineer serving in the Palace in Diyarbakir. The cost was no consideration for his employers, and there was no shortage of servants and slaves. However, his love for automatons constantly sought surprising solutions to the problems around him. This combination of an engineer “crazy” for automatons without constraints won’t be back.
  2. My love M. turned my attention to the Linguist Roman Jakobson and his much-cited article “Linguistics and Poetics” which maps the language to its essential function. For example, The referential function corresponds to the factor of Context, and its role is to transmit information. Some say that this is the main function. I want to focus on the poetic function; it focuses on the message himself, rather than the addresser (sender) or addressee. I took the liberty to take a post of her (in Hebrew) “One Great Illustration and Ora Eitan” and modify it slightly:

“According to the linguist Roman Jakobson” The primary intent of the message as such [in our case, the message is the automaton itself, the way it fulfills its purpose. AG] is the poetic function of language. In Jakobson words: The set (Einstellung) toward the message as such, focus on the message for its own sake, is the POETIC function of language.”

In these terms, al-Jazari is a poet or at least a poet of automata.  In this respect, the discussion on price or maintenance misses the point completely because it treats poetry with traditional engineering tools.

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Two Automatons and Iconoclasm

Introduction

Two automatons, an automaton of a man holding a goblet and a bottle and an automaton of two shaykhs upon a dais, are very similar in their mechanism but also, unfortunately, similar because all the faces of the characters were damaged (thanks to Galia Levy-Grad who brought this to my attention) more on this topic below:

An automaton of a man holding a goblet and a bottle on the right, and an automaton of are two shaykhs upon a dais, on the left. Topkapi manuscript, 1206

How does it work?

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

Both automatons have very partial drawings. Donald Hill, the book translator, did not add a modern schematics as he did with most machines in the book. The reason is Al-Jazari own words: “construction of the figure was described in the previous chapter [here] so there is no need to explain it.” This is my drawing, based on the text and previous drawings:

The mechanism of a man holding a goblet and a bottle

This is a mechanical slave made of copper; the head and neck are a wine reservoir slowly dripping into a tipping bucket. The tipping bucket is partially hidden by his hand. You can see a tipping bucket more clearly in drawing below of the two shaykhs or here (in Hebrew). After seven and a half minutes the tipping bucket would be full of wine and would tilt on its axis and pour twenty dirhams, sixty cubic centimeters of wine which would flow through the pipe to the silver bottle. The top of the goblet is covered; wine would flow directly through the hollow arm to the arm tank. The latter becomes heavy, and the arm would move upward about the axle in the elbow, imitating the motion of drinking. When the tank is full, the siphon ­­­will empty the arm tank, and the hand would descend to its original position.

The automaton of two shaykhs sitting cross-legged on a dais, each holding a bottle and a silver goblet is a duplication of the mechanism just explained. The reservoir is full of water which slowly dripped through an onyx to a tilting pipe. At the bottom of the pipe, a ring was welded, so the pipe is like a “children teeter.” The right side is slightly heavier, and therefore the pipe tilts to the right and water come out on the right. It would take about seven and a half minutes to the tilting bucket to fill (the drawing is just before it overturns) and then water would flow into the pipe inside the column. The rod at the side of the tilting bucket would push the tilting pipe to the left, and the water would flow to the tilting bucket B. After seven and a half minutes it would tilt, and water would flow to other Sheikh’s goblet. This is a drawing of the mechanism with my captions:

Mechanism of the automaton of the two shaykhs

Iconoclasm

In both illustrations, the faces were erased. This is not accidental damage; there are numerous illustrations in the Topkapi manuscript with damage to the face, without comparison to the number of illustrations which have a different kind of damage. I think this is a case of iconoclasm (from Greek: εἰκών image, κλάστειν break) – the destruction of icons or images for religious or political reasons. Although the contemporary contexts (Taliban, or ISIS) Iconoclasm is an ancient phenomenon starting with Abraham, the father of the Jewish people but also important to Christians and Muslims. In Genesis Rabba (Hebrew: בְּרֵאשִׁית רַבָּה) a religious text from Judaism’s classical period, probably written between 300 and 500 CE it is told:

“So he [Abraham] took a stick and broke all the idols, and put the stick in the hand of the largest.

When his father returned he demanded: What have you done to them?

Abraham said to him: I cannot conceal it from you, a woman came with a plateful of fine meal and requested me to offer it to them, and I did. One [idol] claimed: I must eat first, while another claimed: I must eat first. Thereupon, the largest arose, took the stick and broke them.

His father said: Why are you fooling with me? Have they any knowledge?

Abraham replied: Should your ears hear what your mouth has said?!”

Genesis Raba 38, my translation

I will expand about Iconoclasm and Islam below, but Christianity also had its part. In the 8th century, there were heated arguments, sometimes violent, about iconography. The issue was the interpretation of the second commandment: “thou shalt not make unto thee any graven image.” What appears to some Christians as proper worship, perceived by other Christians as idolatry. These arguments led to the smashing of icons. It is interesting to note that this is an example of government-led iconoclasm with the banning the use of icons by the Byzantine Emperor Leo III in 730 AD.

Those who think Iconoclasm characterizes fanatic religions will be disappointed to learn that enlighten ideologies, at least in the eyes of their believers, supported massive iconoclasm. For example, the French Revolution, the origin of the declaration of the rights of man, is one of the darkest periods of iconoclasm. For three years France was destroying art, It began with the smashing of statues of the Kings of France, and continued in methodical destruction of religious icons, engravings, paintings and burning artifacts from the feudal past. The following quote is from a law from 1792:

“Whereas the sacred principles of liberty and equality will not permit the existence of monuments raised to ostentation, prejudice, and tyranny to continue to offend the eyes of the French people, whereas the bronze in these monuments can be converted to cannons for the defense of the homeland …

All monuments containing traces of feudalism, of whatever nature that remains in churches, or other public places, or even those in private homes, shall, without the slightest delay, be destroyed by the communities. “

The opposition to figural representation in Islam is not based on the Qur’an, but on traditions contained within the Hadith ( الحديث). This is a collection of stories about Muhammad and his words and advice regarding various topics. Within Islam, the authority of Hadith ranks second only to that of the Quran. The two principal objections to figuration are a concern with not taking over the divine creative power and a fear of shirk (شرك), a term that came to mean polytheism and idolatry but originally meant believing in other gods. This duality is similar in my mind to what I learned during my studies at the Mandel School for educational leadership: “thou shalt not make unto thee any graven image.” does not ban on idolatry because it was already said “Thou shalt have no other gods before me” and the ten commandments are “the essence” of faith and contain no repetitions. Hence the second part forbids the use of material representation of God and demand spirituality. Either way, there’s consensus Hadith forbidding all representations that have shadows, whose defacement is obligatory. Some schools of Islamic thought go so far as to see all artists that depict living being (animals and humans) as polytheists.

Over the years, some people who interpret this as permission and possibly an imperative to destroy artworks, in many cases as their initiative. A good example is described by the Ottoman writer Evliya Celebi. In an auction in Eastern Anatolia in 1655 potential bidders were allowed to inspect the goods in their quarters at night, and one of them took the manuscript of Shah-Nama, the Persian Book of Kings, and when he saw it contains miniatures, painting being forbidden according to his belief, he took his Turkish knife and poked their and rubbed the color in their faces with his saliva(?).

The offender was eventually lashed and stoned(?) by the orders of Pasha of Bitlis as a punishment for defacing the manuscript. Clearly, his faith was not accepted by the authorities, or maybe the Pasha was annoyed because of the damage value of the goods.

I couldn’t find any material on iconoclasm in the Topkapi manuscript, and I don’t know if the name of the vandal and the time are known. This  is a partial collection of defacing in the manuscript:

I’d like to close this post with something more optimistic, so I wish the world would be less violent or fanatic, and we will not experience any more iconoclasm because of the Christian, Islamic or Jewish faiths nor by any other ideology.

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Automaton of a slave pouring water and the Artuqid court

Introduction

This is a slave made of jointed copper. In his outstretched right hand, he holds a pitcher decorated with a bird. His left hand is raised and in the palm is a towel, a mirror and a comb(not seen in the picture). This copper slave assists the king in Wuḍū – his ritual ablutions.  This is one of five chapters in the book where the King is mentioned explicitly. I went to learn a bit more about the Artuqids and the Palace in Diyarbakır.

Automaton of a slave pouring water, Topkapi manuscript, 1206.

 How did it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in siphons, floats, and pulleys can skip those bits. Essentially the mechanism is very similar to the Automatic Pitcher with a few additions, typical of al-Jazari. I modified the original drawing by al-Jazari and added captions to help follow the mechanism:

A modified drawing by al-Jazari with my captions, Topkapi manuscript, 1206.

In the beginning, a human servant removes the copper slave’s hat and pours water with a funnel into the water tank in the slave chest. In the drawing, the tank is half full. At the bottom of the tank, there is a rotary valve (in red). The servant brings the automaton to the King and rotates the hidden valve rod (in grey) near the neck. Water starts to flow through the pipe to the pitcher. There is a partition in the pitcher and the Pitcher spout, designed in the shape of a peacock’s neck, is a Siphon almost touching the partition. When the water rises they will block the airway through the spout, and the air only way out is through the whistle which will make a whistling sound. This is the part that was forgotten in the “Automatic Pitcher.” The siphon, spout, the partition, and even the rotary valve are identical to the “Automatic Pitcher”. The hand holding the pitcher is hardwired and will not move. The hand with the towel consists of an arm and forearm with an axis at the elbow and is free to move. The float is connected through the pulley to the elbow and would sink as the water exit, pulling the arm so that copper slave will offer the towel to the king.

For whom Al-Jazari designed his machines?

In the first chapter, “the Castel Water Clock” al-Jazari wrote :

” This is the basis of the work. Individual parts may be omitted or added according to the place for which it is constructed. For mosques and shrines it may be limited to what is necessary for telling the hours; for the palaces of kings, what may be fitting, such as pictures and other things.”

Naturally, I assumed that all al-Jazari machines were designed for the King and his court, after all, al-Jazari was the court engineer. But when I inspected the book carefully it turns out that the King was mentioned explicitly only in five chapters, including the current “Automaton of a slave pouring water” In only two chapters the  King is mention by his name King Salih, i.e. Salih Nasreddin Mahmud who ruled in Diyarbakir during the years 1200-1222. There are nine more chapters like Category VI chapter one, “the Palace Door” (only in Hebrew) or Category II, chapter four, ” A boat placed on a pool during a drinking party ” (also only in Hebrew) where the King is not mentioned, but from the description and the circumstances the machine was clearly designed for the Royal Court. There are thirty-six chapters which are machines with an unspecified designation. Nobody knows where the Elephant Clock or the Perpetual Flute were located at the time. They could be in the central square, the Palace itself or in some magnificent mosque. I don’t want to pretend that al-Jazari was an engineer in the service of the public. All he did was probably with the Artuqid King blessing. I set out to learn more about Artuqids and their court.

Artuqid kings

Al-Jazari had served three Artuqid kings. Only one of them is mentioned in the book by name: Salih Nasreddin Mahmud who ruled Diyarbakir 1200-1222.

Before him, al-Jazari served his brother Quṭb al-Dīn Sukmān II in the years  1185-1200 years, and he started his service in the Artuqid court for their father  Nūr al-Dīn Muḥammadin in 1181. All three are pretty minor figures in the history of the 12th and 13th centuries. Carole Hillenbrand, Professor Emeritus of History, University of Edinburgh wrote the book: “A Principality in Crusader Times Is: The Early Artuqid State” and several articles, but they contain mainly information about battles and alliances and less about the cultural life. I think if we remember the Artuqid is mainly due to its cultural enterprise. Twenty years or so before al-Jazari the Artuqid court hosted Usama Ibn Munkidh, a Muslim poet, author and knight who wrote كتاب الاعتبار‎ translated a to English as “The Book of Contemplation” which is probably the best-known Muslim source for the Crusader period. Upon the request of the Artuqid king, almost thirty years after the death of al-Jazari, al-Jawbari (الجوبري ) wrote “Book of Selected unveiling of Secrets.”This is a concise encyclopedia of tricks, practices, and devices used by fraudulent Ṣūfīs, false alchemists, jugglers, and quacks. To the best of my knowledge this was not translated to English (unfortunately!). You can add a new architectural language in Artuqid mosques explained in the Thesis of Sharon Talmor Sol(TAU) and Rachel Ward’s paper which present evidence for a workshop for copying manuscripts the Artuqid court. What was the cause of this cultural flourishing?

It is certainly not the size. The title “King” is perhaps a bit excessive. This is the map in the 12th century:

Map of the Principality of the Artuqids in 1200. Wikipedia.

The Artuqid Principality, as you can see, was tiny. Most of Turkey’s territory was controlled by the Byzantine Empire and the Sultanate of Rum. The later is what remained of the Seljuk Empire that controlled, at its prime, a vast area stretching from India to Antioch and from the Arabian Peninsula to Azerbaijan and contained most of the Muslim territories in Asia. However, by the 12th century, the Seljuk Empire was in decline, enabling the existence of small Principalities like the Artuqids. It’s not just the modest territory. Saladin, Sultan of Egypt and Syria, the founder of the Ayyubid dynasty in Cairo took Diyarbakir by storm in 1183 the Artuqids ruled by his grace. It is interesting to note that on the southern wall of the Palace in Diyarbakir appears الله اَلملك واحدي which means Allah is the ruler and drawing of Trebuchet. The Trebuchet is a powerful siege engine which uses a swinging arm to throw a projectile towards besieged city walls. In the second half of the 12th century, the Trebuchet was significantly improved, and those improvements appeared in a military manual written for Saladin. The drawing of the Trebuchet on the walls of Diyarbakir is unique, as far as I know. It can be interpreted as a quality assurance like “this wall would survive a barrage of Trebuchet” or it can be to commemorate the siege by Saladin as “Remember my siege and the horrendous Trebuchet I brought on your heads ” and maybe there is a different explanation altogether?

Picture of the Trebuchet on the southern wall of the fortress in Diyarbakir. Photographed by Lorenz Korn, 2008.

The historical information about the Artuqids doesn’t help me to understand or think about the book. There’s something very optimistic and perhaps even wonderful how this tiny Principality produced such a significant cultural-engineering heritage “It is impossible to overemphasize the importance of Al-Jazari’s work in the history of engineering, it provides a wealth of instructions for design, manufacture, and assembly of machines” Donald Hill in the History Engineering. From the foreword by Donald Hill.

I am adding two pictures of the Palace in Diyarbakir. This is the view from the palace of the  Valley of the Tigris. In Hebrew, the river is called ” Ḥîddeqel” following the ancient Akkadian name ” Idigina”. Most languages in the world follow the old Persian name, Tigrā:

Photo of the Tigris Valley view from the Palace.

Below is the Ulu Beden Tower, a black basalt stone tower in Diyarbakır. It was built in 1208, two years after the death of al-Jazari at age 70.

Ulu Beden Tower, Diyarbakir palace.

The double-headed eagle, the winged beasts and the beautiful Kufic inscription are, in my mind, related to the book. The double-headed eagle also appears on a coin of dirham minted by Mahmoud Nasreddin (the King of Al-Jazari):

A Dirham, 1218, minted in Ḥiṣn Kaifā where the Artukids court was before Diyarbakir.

Some claim that the double-headed Eagle is a Byzantine icon, and one head is facing Rome, and the other one is facing Constantinople. However, the double-headed Eagle symbolizes power and control from the time of Hittites and has countless appearances before and after Byzantium. Are the Tower, the currency, and the view of the Tigris valley helping you see al-Jazary at work? You decide.

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The Arbiter for a drinking session

Introduction

This is a drinking game for the effervescent parties in Diyarbakır Palace as we met in The automaton who drinks the king’s leaving and A boat placed on a pool during a drinking party (in Hebrew).

The Arbiter is a complicated automaton (a self-operating machine) which includes: A slave (جارِية) pouring wine to a goblet in the lower level. Above her, on a balcony, there are four slave girls who play music on a flute, tambourine and a lute. Above them, there is a half-naked male dancer in a niche, and on top of the dome, there is a horse rider carrying a lance. During the party, the musicians play their instruments, the dancer dances (I swear!) and the horse and the rider rotate slowly. When commotion stops the slave girl tilt the bottle and pours wine to the goblet. A servant (a living person) takes the goblet and serve it to the participant the spear points to his direction. The process repeats itself twenty times, almost seven hours in total. At that time the black doors behind the dancer open and a man emerges out of the door, his hands are in the air, signaling that celebration is over and there is no more wine. Al-Jazari calms the worried reader, saying that the head of the assembly can choose to refill the reservoir. The wild parties in Diyarbakir can raise a lot of questions about the crazy amounts of wine, the half-naked dancer, and more. Maybe I will write about all this in the future. I want to focus on clothes, did observer of the automaton in the 12th century knew she was a slave by her dress?  What can we learn from the text and the illustrations about clothing in the Artuqid palace?

The Arbiter for a drinking session. Topkapi manuscript, 1206.

How does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in floats, Tipping buckets or camshaft can skip those bits. The illustration below is my modification of the drawing from the book; it will help us to follow the mechanism:

Drawing of the mechanism

In the beginning, a servant lifts the dome (1) and fill the reservoir (2) with filtered wine.  At the bottom of the reservoir, there is a thin pipe, so wine is dripping to the tipping bucket(3). I wrote about tipping buckets before, for example in the fountain of the two tipping buckets (in Hebrew). In the front view, you can see the tipping bucket in action. After twenty minutes the bucket is full of wine, and it becomes overbalanced, and tips down, emptying itself on the scoop wheel (4) which turns the adjacent teeth wheel (5) which turns the 900 teeth wheel(6) which is connected to the rider axle(more clearly seen from the side). This makes the rider rotates, and the “lucky” participant that the spear is pointing in his direction will get to drink the goblet. I used quotation for “lucky” because the goblet contains a liter of wine, more than an entire bottle! I don’t know what the alcohol content in the 12th century was, but it seems like a sure way to get drunk with a severe hangover. I do not want to think about someone who was lucky enough to win two goblets during the seven hours of the party.  The wine from the scoop wheel is collected and falls on the second scoop wheel(7). The rotating wheel rotates the axle and the pegs(8)connected to it, hitting the levers connected to the musician’s arms. This causes the up and down movement, simulating the drummer bit and the playing of the lute. The rods, an early version of camshaft transform the circular motion into linear motion were the rods pattern creates different drumming bit and lute music. The wine flow from the 2nd scoop wheel to the air tank, pushing air in a narrow pipe with a whistle at the end(9). This produces the sound of the flute player. Finally, the wine goes down in a hidden tube (10) through the slave body and fills the bottle. The latter is on an axle, and the weight will cause it to tilt and fill the goblet. For clarity, I skipped two mechanisms. Readers who love to ponder on this kind of gadgets can try to decipher the remaining components and questions will be, as always, appreciated.

Fashion and clothing in the “Book of Knowledge of Ingenious Mechanical Devices.”

The choices of clothing by Muslims reflect their religious and cultural world. We call the veil worn by some Muslim women to cover their hair- hijab (Arabic: حجاب). In the Qur’an and other classical Arabic texts, the term was used to denote a partition, a curtain and it is a generic term for modest attire. During the Hajj (حَجّ), the pilgrimage to Mecca, one of the five pillars of Islam, the men wear a white outfit that was not touched by a needle or thread (how is that even possible?).  What (if anything) can we learn about life in the 12th century in Diyarbakır by looking at the illustration and the few direct references of al-Jazari to clothing details?

Five slaves from the “Book of Knowledge of Ingenious Mechanical Devices” Topkapi manuscript,1206

In the top left illustration, we can see a young black slave (غلام) truncates the candle wick from The candle clock of the swordsman (Hebrew). No explicit description of him in the book but his attire is the simplest, in comparison to all the other slaves and includes a short red dress with stripes on the sleeves. The sleeves’ stripes appear in almost every dress of slaves or free men. I don’t know if this was the fashion in Diyarbakır or the stripes had a meaning or use? If a knowledgeable reader can enlight me, I would love to learn.

The slave girl pouring wine at the center is from the automaton in the present post. She wears a blue dress or gown with decorations that cover her from neck to ankles. She also has two brown stripes on her sleeves. The garment doesn’t look “cheap” or “service uniform” Her black hair can be seen under the cover. Although her dress could have been worn by devout Muslim today her head cover is not acceptable by contemporary moderate standards (hijab) and certainly not by more religious Muslims demanding a niqāb or chador.

We met the slave washing the king’s hands here (in Hebrew). The illustration, in this case, is large and rich with details. The blue dress is very similar, if not identical, to dress of the slave girl. It is particularly interesting. Muslim men are forbidden(حَرَام‎ ḥarām) to wear silk clothes or gold jewelry. This is not from the Quran but a later story told by Ali Ibn Abi Talib, Muhammad cousin and the fourth Caliph accepted by both Sunni and Shia. The restriction is very specific but interpreted as an echo of the biblical verse:

“The woman shall not wear that which pertaineth unto a man, neither shall a man put on a woman’s garment: for all that do so are an abomination unto the Lord thy God.”

(Deuteronomy 22:5 King James Version)

It is possible that his red jacket without sleeves is enough to distinguish between them? He is also wearing a small red hat quite similar to the fez (more correctly ṭarbūsh). It is interesting to note because the ṭarbūsh is usually attributed to the period of Sultan Mahmud II (1808-1839) when it was introduced as part of the Ottoman Empire judges and spread to clerical circles and the educated elite.

The next slave, to the left and below, is from the automaton of a standing slave holding a Fish and A Goblet. In this case, al-Jazari himself provides a relatively detailed description of the dress:

” He is a standing slave, ten years old in appearance, dressed in a short jacket (farajiya) with a robe(qaba) underneath it, and a cap (qalansuwa) on his head.”

The qaba (قابا, I hope I spelled right?) is a type of a robe with sleeves, at mid-calf –between the knee and ankle that has a diagonal fastening of one side over the other. The “Encyclopedia of Islamic Civilization” claimes that in Abbasid times qaba belonged to the military? According to the illustrations in the book, the qaba was widely used among slaves and free men. The hat (qalansuwa  = قلنسوة‎) is written like the Arabic city in the center of Israel; I don’t know if this is the origin of the city name. This hat was quite popular, and Harun al-Rashid was wearing this hat in his nocturnal wanderings through Baghdad in disguise. Unlike the qaba which repeats itself in many illustrations, there is quite a selection of headdress. For example, the slave girl who emerges from a cupboard holding a glass of wine is covered with a colorful scarf with a picturesque ribbon. Quite similar to today hijab. She is also wearing loose red trousers under the qaba. This combination can be found both in the book and outside.

Eight “free” people (in the sense of not slaves) from the “Book of Knowledge of Ingenious Mechanical Devices” Topkapi manuscript,1206.

The top left illustration is the scribe from the elephant water clock. There are three scribes in the book, all three wear green qabas with brown stripes on the sleeves and wear pale blue turbans. I couldn’t find any evidence of “professional clothing” of scribes. You should also note that the scribe has a beard. Allowing the beard to grow (لحية) and trimming the mustache is mandatory in Sunni Islam and is considered to be Fitrah (فطرة‎) or the state of purity and innocence we are all born with including the natural tendency to distinguish between good and evil and to believe in the existence of Allah. As none of the slaves are bearded, they probably weren’t Muslims.

The two Sheikhs are part of the automaton in Category II dedicated to vessels and figures suitable for drink sessions.  Al-Jazari did not write anything about the Sheikhs, but Sheikh (( شيخ is a title given to the leader of the Bedouin or Arab tribes. The meaning of the name in Arabic is old, although the Sheikh is not necessarily old. They are also dressed in qaba and turbans. I don’t see in the illustration a difference between the of Sheik’s qaba and the slaves’  qaba. It is quite possible that there were large differences in the quality of the cloth or decoration which are not captured in the illustrations. However, the turban characterizes only the free people. Before anything else, the turban was practical in protecting the eyes from the sand and providing the face protection from the sun.  On top of this, the turban (عمامة, pronounced amama) was part of Muslim’s traditional attire and their identity. The turbans were a source of pride and a symbol of religious affiliation. Taking a man’s turban was considered a humiliating act, touching someone’s turban was perceived as an insult. It explains well why none of the slaves wear a turban.

The last picture below is from the musical boat(Hebrew). This is the King and his boon companion ( نديم =Nadim) I wrote about it here (Hebrew). Everyone is wearing a qaba, including the King himself. His blood-red qaba has gold trim. On top of the decorations, everybody has, he has additional decorations of the collar, the cufflinks and the fringes of the qaba as well as a golden belt. Red is not necessarily Royal, another member of the party is wearing red, though with fewer decorations.

I’m pretty sure al-Jazari was very surprised from this post, and it didn’t occur to him that the illustrations he prepared to improve the understanding of his machines, and are truly groundbreaking, would become a fashion guide for 12th century Diyarbakir. However eight hundred and twelve years later this is the only window that would allow me to peep into the  Palace in Diyarbakır. At least for me, this was an interesting journey.

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The Elephant Clock – Multiculturalism or a Circus?

Introduction

The elephant clock is by far the most popular of all al-Jazari’s works. There are a few modern reconstructions of it: some in different exhibitions and museums, but also one in the Dubai Mall. The clock has a variety of animations in 2D and in 3D, and it even has its own Wikipedia page. Due to the complexity of the mechanism, I divided this post into two; in the first part, I will explain what the viewer sees and try to explore the sources of the magic. The second part will be more engineering-oriented, and I will explain how the mechanisms work in the backstage, and what is so unique about this clock.

The Elephant clock, manuscript from 1315, Syria

What does the viewer see?

An elephant,  approximately one meter and twenty centimeters long, who is carrying on its back a canopy with four pillars and a castle. On top of the castle’s dome, is a bird. Inside the elephant, is a hidden water reservoir and a sinking float (a float with a hole that sinks slowly) during half an hour. More details in the next post. In the canopy sits a scribe holding a pen pointing at a semi-circle with tick marks. During this half hour, the scribe rotates and his pen indicates the minutes that have passed. At the end of every half hour, the scribe returns to its original position. At the same time, there will be quite an impressive show. Between the elephant’s shoulders, rides a mahout (the elephant keeper and driver). In his right hand, is an ax and a mallet in his left. Every half hour the mahout strikes the copper elephant, first, with the ax and then with the mallet. In the castle balcony sits a man. His hands are on the heads of two falcons which he keeps them from opening their beaks. Once every half hour, he raises one of his hand, and the corresponding falcon shoots out a ball. The ball falls into the dragon’s maw, making the dragon swing on its axis and then lay the ball on the cymbal in a jar. During this time, the bird on the dome is also spinning. Above the head of the falconer is a semi-circle with fifteen black holes. Every full hour one hole turns so that the sum of white indicates the number of hours passed since sunrise.

You can see a short video demonstrating the elephant clock and explaining the mechanism:

 A fuller explanation will also come in the next post.

Why an elephant?

The Elephant water clock entry in Wikipedia reads:

“The elephant represents the Indian and African cultures, the two dragons represents ancient Chinese culture, the phoenix represents Persian culture, the water work represents ancient Greek culture, and the turban represents Islamic culture signifying the multicultural mentality of the intellectual al-Jazari. “

The quote certainly is not by al-Jazari, but whoever wrote it explained the wealth of the clock. Nonetheless, it made me think. I am afraid that the whole concept of multiculturalism is completely foreign to the 12th century and al-Jazari. What is a possible explanation for the elephant?

The Middle Ages and strange elephants

The trade routes in the middle ages were spread over Europe, the Middle East, India, China, and  Africa. On the east coast of Africa, they traded ivory, gold, ebony, and slaves. China exported silk and porcelain, India spices and drugs. Rumors about elephants, giraffes, and other exotic animals reached Europe but the artists who drew the manuscripts had never seen an actual elephant. They drew them based on their imagination. There is an entire site dedicated to the weird drawings of elephants. I give just two examples:

Thomas of Cantimpré, Liber de natura rerum, France 1290

A hoofed wooly elephant “Livre des simples médecines” a manuscript from the 15 century.

The original manuscript by al-Jazari was unfortunately lost, but the manuscript from Topkapi is from 1206, I wrote about it here. This is the year al-Jazari died, so it is probably a copy of the original. You can see that the elephant looks like an Asian elephant and the mahout and the canopy are located correctly. Al-Jazari’s familiarity with elephants is not necessarily surprising, although I couldn’t find any evidence for elephants in Diyarbakir. Arab rulers had menageries or collections of exotic animals. In addition to the curiosity and pleasure they provided, they demonstrated the ruler’s wealth and power as well as the impact of the sovereign from India to Africa. Offerings of rare animals were part of the diplomatic process and sometimes part of the tax system. Until the 13th century, the agreement between the Nubian Kingdom and the Muslim rulers of Egypt demanded that the Nubian people provide Egypt with three hundred and sixty slaves annually, in addition to providing some wildlife. It This was the primary source for giraffes in the Sultan of Cairo’s menagerie.

Book of the animals, Syria, 15th Century.

The use of animals as a diplomatic gesture is well documented. For example, Baybars, the Mameluke Sultan of Egypt and Syria in the 13th century gave elephants, giraffes, and zebras to the king of Spain, Emperor of Byzantium and the Mongol Khan. In the 10th century, Cordoba sent a giraffe to Tunisia and a story I particularly like about the elephant, Abul-Abbas. Harun al-Rashid,  the Abbasid caliph in Baghdad, sent an Asian elephant to Aachen, Germany to the Carolingian emperor Charlemagne. It happened in the 9th century, and surprisingly enough, there’s a Jewish angle to this story. The elephant was brought by Yitzhak the Jew. There is a historical novel “The travels of Isaac the Jew and Abu Alabas the elephant”(in Hebrew). It is interesting to note that other presents including an elaborate water clock made of brass, described in the Royal Frankish Annals were sent with the elephant. The water clock marked the 12 hours with balls of brass falling on a plate every hour, and also had twelve horsemen who appeared in turn at each hour.  Perhaps al-Jazari knew the story as part of his extensive knowledge of water clocks?

The Elephant Clock and the Circus

The diplomatic delegations and the royal gifts indicate that the elephant was a symbol of power and wisdom, but in the context of the elephant clock, I think more about the circus and exotic acts. The elephant is made of copper and is just a stage for the show, but the swinging dragons, the Mahout with his fearsome tools, the Falcons and the spinning bird form a great circus number. An exciting circus act has, in my opinion, four components, not in binding order, not always all of them, and certainly not of the same significance or importance:

  • Freshness (something new)
  • Great skills
  • A sense of danger
  • An awe-inspiring images

I looked at several iconic circus shows and Jules Léotard’s act is a good point of comparison. Léotard was a French acrobatic performer who made history as the first man ever to perform the aerial act on a trapeze. It most certainly meets the requirement for freshness. Likewise, the elephant clock is also the first of its kind; no clock ever, before or after, is similar, and everyone who watches it, even today, is amazed.

Secondly, great skills: Léotard practiced his acrobatic stunts over his parents’ pool before he revealed them in 1859 in Cirque Napoleon in Paris. Then he appeared in London before an audience that went crazy because of his aerial flips between five trapezes with only a pile of mattresses to protect him. The elephant clock also demonstrates such high proficiency and skills both to the innocent and to the skilled observer, considering the control of the timing using the sinking float, the complex movement of the three characters(the mahout, the scribe, and the man in the balcony), and the virtuoso swing of the dragons. All are innovative engineering tricks demonstrating al-Jazari’s skills in water clocks and automatons.

Regarding the sense of danger, the crowd in the circus was afraid for Léotard’s life and this element intensified the experience; however, automatons by definition lack this aspect.

Jules Léotard, a French acrobat, 19 century

Last but not least, the awe-inspiring image. Léotard, like all circus performers, could be dressed in a sports suit, but as you can see in the picture he’s wearing theatrical shorts, bracelets emphasize his wrists, and the collar of his shirt reminds us of a royal necklace. All this help to imprint his image in our mind.  The picture that al-Jazari created is a lot more than the sum of its components and is intriguing audiences till this very day.

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The Castle Clock

Introduction

Al-Jazari opened  “The Book Of Knowledge Of  Ingenious Mechanical Devices”  with a monumental clock, perhaps the most complex of all ten water clocks and candle clocks explained in the book: The Castle Clock.

Sometimes you know you read a wonderful book the second  you read the first paragraph:

“Call me Ishmael. Some years ago – never mind how long precisely – having little or no money in my purse, and nothing particular to interest me on shore, I thought I would sail about a little and see the watery part of the world. It is a way I have of driving off the spleen and regulating the circulation.”

Moby Dick by Herman Melville

In the right hands, the beginning of a novel can make you feel like you were abducted from reality and you are drifting down a river which will take you to other worlds. Not only engineers who open al-Jazari’s book are captured immediately by its magic of the machines he designed eight hundred years ago. We will never know if al-Jazari wanted a powerful opening to demonstrate his ability at its best, or he positioned machines at random order and was surprised by the very question? This post hopes to explain the Castel Clock as well as discuss what we can about al-Jazari from the text.

How does it work?

The Castle Clock had a complicated movement throughout the day, and it is on the boundary between a clock and an automaton(a machine that performs a function according to a predetermined set of instructions). There is something theatrical in many automata. Sometimes it is by design, like the automata in Greek theater used for “Deus ex machina”, literally “god from the machine”. Sometimes there are other objectives like the lion automaton built by Leonardo da Vinci for François Ier, king of France. When the King tapped the lion with his sword, its body opened and presented lilies, a symbol associated with the French royalty. The clock by al-Jazari is also very theatrical.

The Castle Clock from a dispersed copy, 1315.

At the beginning of the day all twenty-four doors, in two rows, are closed and the Golden Crescent,  which is a little hard to see in the picture, is positioned to the left. During the day, the half-moon is moving right, and  every hour three things are happening:

  • The upper doors open and a figure comes out and stands as if he had suddenly emerged.
  • The lower door is rotating on its axis, and the text “Allah al-Malik” meaning ” God is The King and Owner of “
  • The Two falcons with outspread wings lean forward and cast a bronze ball into a vase, inside the vase a cymbal is hung, making a sound which can be heard from afar.

The picture of the falcon is taken from a dream or myth. Horus is one of the most significant ancient Egyptian deities. He was most often depicted as a falcon. Horus had many battles with Seth, the god of the desert, in which he lost his left eye, then a new eye was created for him called “the eye of the Moon” or “the diamond” and symbolizes an endless vision. I have no reason to assume that al-Jazari was familiar with Egyptian mythology, but who knows?

Above the upper row of doors, we can see the Zodiac sphere. At the beginning of the day, the sun will be on the eastern horizon, about to rise. The sun climbs until noon, then descends until nightfall and the six signs that have been visible will disappear, and the six that have been hidden will appear. At noon the drummers drum, the trumpeters blow, and the cymbalist plays his cymbals for a while.

Al-Jazari does not write anything about the reason for multiple mechanisms to display the time. The crescent actually functions as a modern analog clock hand, and the rest are just “decoration” and maybe a resonance box. In the world of modern engineering, it could be considered excessive and even wasteful, but there is magic that passes through centuries of the Falcons even if there is no additional information.

Erich Kästner, the wonderful author of Pünktchen und Anton(Dot and Anton in English), was concerned:   ” By the children who would prefer to eat porridge for three days than deal with such complex issues as his reflections [my translation from Hebrew]. He came up with a different font “so if you see something like that you can skip it altogether…” It seems to me this even more needed for technical explanations of engineers that will be in blue.

The Castle Clock is a sophisticated version of the classical water clock or clepsydra where time is measured by the regulated flow of out a vessel where the amount is then measured.  The difficulty is that the water flow rate is not uniform and depends on pressure (altitude) of the water in the vessel. To overcome this problem, al-Jazari used a conical plug and the float chamber.

Conical plug, the Castle clock, Topkapi, 1206

The main reservoir is feeding the float chamber through a conical plug thus whenever the water level drops the valve (a float that is a plug in a cone shape) goes down with the water level allowing the chamber to be refilled. Every time the chamber is full of water, the conical plug will seal the chamber isolating it from the main reservoir. In this way, the float chamber is always full of water and therefore the water flow at a constant rate and does not depend on the height of the water in the main reservoir.

A drawing of the clock mechanism, Topkapı manuscript, 1206, my captions

 

At Sunrise a servant makes sure that all doors are closed and the time cart is on the right side (looking from the back). During the day water will flow at a rate determined by the flow regulator and the main float would drop with the water level at the main reservoir. The main float is made of copper, and it is quite heavy.  When it drops, it pulls the rope, which through the pulley would turn the main disk and pull the time cart attached to the golden crescent which would move to the left at a constant velocity indicating the time passed from sunrise. Every hour the cart will progress one door, and a smart mechanism would open the doors while dropping down two bronze balls. The balls would roll down and reach an opening above the heads of the Falcons. The curving claws of the Falcons are welded to a copper tube that can rotate on its axis. The falcon stands upright because of a balancing weight. When the bronze ball drops down, it changes the balance, and the falcon would lean forward, and the falcon wings, attached to a body on a hinge will spread open, and the ball will fall on the cymbal hidden in the vase. Now that the falcon head is light again, the balancing weight will bring him to its original position. The clock is packed with similar invention and  “patents”.

A drawing of the falcon mechanism, Topkapi manuscript, 1206

The book contains almost 50 pages explaining the various mechanisms with detailed construction instructions. Readers who are interested in the details can learn them here and see the simulation here

 

What did I learn about Al-Jazari?

We have no information about al-Jazari except what is in the text itself. We can “pick” the book to learn about al-Jazari and his world. Consider the adjustable flow regulator intended to ensure that the clock movement fits the changing length of the day. This controller is a small engineering marvel itself, but I am interested in it because of the triple encounter it offers with al-Jazari and his world:

  • First, al-Jazari is a man who is familiar with the literature of his time. The opening lines of the Castle clock chapter are: “I followed the method of the excellent Archimedes in distributing the twelve signs of the Zodiac. Al-Jazari is probably referring “On the construction of water clock” – كتاب أرشميدس في عمل البنكامات. This book was attributed to Archimedes, but its source is unclear. This reinforces al-Jazari statement in the introduction:

“I have studied the books of the earlier [scholars] and the works of the later [craftsmen] –masters of ingenious devices with movements like pneumatic [movements], and water machines … I considered the treatment of this craft for a period of time and I progressed, by practicing it, from the stage of book learning to that of witnessing, and I have taken the view on this matter of some of the ancients and those more recent [scholars]. “

The question of openness or seclusion to the world for people of faith is a relevant question even today for Jews or Muslims.    Maimonides, Rabbi Moshe Ben Maimon, the most important rabbinical arbiters in Jewish history, and polymath, scientist, and  physician lived almost in the same time frame in Cordoba, far away from Diyarbakir in Anatolia but he was a part of the same  Muslim world. During his medical studies, he was introduced to the writings of Aristotle in natural science and did not feel any threat to his faith. He even wrote:

” Consequently he who wishes to attain to human perfection, must therefore first study Logic, next the various branches of Mathematics in their proper order, then Physics, and lastly Metaphysics.” Guide for the Perplexed

It’s amazing to read when today Orthodox Jewish children are forbidden to learn mathematics or natural sciences. Al-Jazari, more engineer than a philosopher, does not deal with matters of faith directly, but his faith is embedded in the text. This doesn’t bother him at all to read and learn from pagan scholars.

  • Secondly, in Diyarbakir in eastern Turkey, there are little more than fourteen hours of daytime in the summer and approximately nine hours of daytime in winter. Al-Jazari made a considerable engineering effort ensuring that there would be twelve hours between sunrise and sunset in summer and winter. This is the purpose of the flow regulator which adjust a short hour in the winter compared to the longer hour in the summertime. Time is not an illusion or a pure man-made concept. The Earth orbited the sun before there were humans around and the sunrise and the sunset, as well as summer and winter, were here before we gave them their name. But the perception of time and its measurement are human inventions. If I would have met al-Jazari and told him that a second that was impossible to measure in his time is the basic unit of time and its scientific definition is approximately 9 billion (for those who want precision 9,192,631,770) cyclic switching between two energy levels of the atom cesium. Not only would that he would not understand a word but also would think me really He did not need such precision that did not fit his daily experience. But I use Waze, a navigation application, and we need accurate atomic clocks at this level of precision to bring me to my destination on time. In today world, the concept of time which varies according to the seasons seems far-fetched, but in the world of al-Jazari who knew sundials and water clocks, it made perfect sense.
  • Thirdly al-Jazari made detailed measurements of the water regulator attributed to Archimedes and found it insufficient. Then he explains in detail how he tries to solve the problem without success through trial and error. It’s ridiculous to compare a modern engineer to al-Jazari, but it is delightful to read the report of a very talented engineer more than eight hundred years ago. It turns out that his concerns are not very different from the concerns of a current engineer. From the text, it turns out he did a “literature review” and theoretical calculations (in this case unsuccessful), and plan and perform the experiments. He was also a skilled man who knows copper, bronze and wood and their processing. When al-Jazari explains, for example, how to prepare the main water reservoir, he’s not satisfied with a drawing and selecting material (copper) but explains how to get a perfect cylinder with a precise wooden disk and how to ensure that the cylinder would have the same diameter all along. For the technical reader, it is easy to sympathize with the difficulties and solutions. There is something appealing in this combination of a man of the books, an engineer, a craft master and an artist who we can meet through the pages and the hundreds of years that passed.