History

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The Scribe Candle clock, on clock face and hands

Introduction

The Scribe candle clock is the second scribe holding a pen out of three scribes that appear in the book. The scribe rotates continuously and passes fifteen degrees every hour, so one degree (one marking) is approximately four minutes. We already met a scribe holding a pen in the elephant water clock (in Hebrew), and soon I hope to write on the beaker water clock that has a different mechanism, but a very similar scribe. The scribe and his pen are used as a hand in a clock. It reminded me “modern” analog clocks and made me go back and examine the development of concepts such as minutes and seconds and the development of the clock dial.

The candle clock of the scribe ” Book of Knowledge of Ingenious Mechanical Devices” Topkapi manuscript, 1206.

How does it work?

Al-Jazari opens this chapter:

“I came upon a clock made by Yunus al-Asturlabi which had the appearance of the clock I described in the first chapter[ meaning the candle clock of the sword men]. A cross-beam which had a hole in its center for the wick replaced the cap which I used to hold the candle down, and I discovered that the wax flowed into the interior of the sheath and over the instruments inside the sheath. .. This gave much trouble; for this reason the design was useless. “

We do not know who Yunus al-Asturlabi was. Eilhard Wiedemann, a German physicist, one of the first researchers of science in Islam, who did much to bring the work of the al-Jazari to the west, suggested the astronomer and mathematician Ibn Yunus. Probably we will never know for sure. Correct identification or not, it is quite interesting because we have no evidence of any sophisticated candle clocks before al-Jazari’s.

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. The drawing below is by the book translator and annotator Donald R. Hill with my captions:

A drawing of the mechanism by Donald Hill with my captions

The candle is placed on a holder inside a brass sheath, and only the wick protrudes through a hole in the cap. A long rod is soldered to the bottom of the holder. The rod runs through the main weight so that the weight is free to move up and down. Two strings are connected to the bottom of the rod and through two pulleys to the main weight. The latter is relatively heavy, slightly more than one kilogram. At nightfall the wick is lit, at that time the candle is in full size, the rod reaches its lowest point and the main weight its highest. As the candle is consumed, the main weight will descend exerting force, through the pulleys, on the holder upward and the holder and rod will go up at a constant rate depending on the rate of the combustion. A string which turns the scribe is attached to the bottom of the weight. Every hour the scribe and his pen will cover 150, so one can tell the time within 4 minutes. The holder pulls the ball’s channel up and every hour the highest ball in the channel has risen until it is level with the hole in the back of the falcon’s head, at which point it rolls out and falls from the falcon beak.

Minutes and their measurement

The globe and the clock face owe their divisions to a numerical system which is four thousand years old. The Babylonians made astronomical calculations using Sexagesimal (base 60) numeral system.  We can only conjecture why people of the ancient Middle East (Assyrians were also Sexagesimal ) adopted the use of base 60. One assumption is that the number 60 was chosen because it is the first number divisible by all the numbers 1 to 6. Alternatively, base 60 was preferred because the lunar year contains three hundred and sixty days. There are more suggestions. Hipparchus of Nicaea already mentioned here(Hebrew), as well as other Greek astronomers, used the tools previously developed by the Babylonians astronomers.  Hipparchus used the geometry of a sphere to find locations on Earth. There were attempts to use grid lines before, but he was the first to apply rigorous mathematical principles to the determination of places on the Earth’s surface, by specifying their longitude and latitude in terms of 3600 running South to North(longitude) and parallel to the equator(latitude).

Claudius Ptolemy considered the most famous astronomer of antiquity. His book the Almagest, from Arabic  (المجسطي) is considered to be one of the most influential scientific texts of all time. Its geocentric model whereby planets revolve around Earth was accepted for more than twelve hundred years until the work of Nicolaus Copernicus in the 16th century. Ptolemy used and expanded the work of Hipparchus by subdivisions of 3600 of longitude and latitude into smaller sections. Each degree was divided into sixty parts called “partes minutae primae” literally “the first small part.” This was later reduced to minutes. The minutes were further divided into sixty “partes minutae secundae” or “second small parts.” Later reduced to seconds.  Interestingly enough the time units in Hebrew “DAKA” and “SHNIYA” reflect the historical names.

Clock still didn’t show minutes and seconds for hundreds of years after the Almagest, partly because of technology limitations and partly because there was no need. In the middle ages, the meaning of an hour as sixty minutes was not understood by most people. Not many mechanical clocks from the fourteenth century are left, but those I could find do not have hands, in most cases, and ring a bell to indicate the hours.

The Salisbury cathedral clock is said to be the oldest working clock in the world. It is dated to 1386 (not certain). It is a large iron-framed clock without a dial and obviously with no hands. There are other clocks competing for this title. None of them has minutes’ hand:

The Salisbury cathedral clock

The Forchtenberg clock tower in a small town in south Germany is one of the oldest surviving mechanical clock towers. In contrast to the controversial dating of the Salisbury cathedral clock, the year 1463 is carved in iron. The only uncertainty; was the clock made at this date? Or could it be older and this is the first repair date? This clock has only an hour hand:

The Forchtenberg clock tower

Who was the first to install the minute hand? It is not clear, but the second hand has a story we know. Jost Bürgi was a Swiss clockmaker, a maker of astronomical instruments and a mathematician. He was employed at the Court William IV, Landgrave of Hesse-Kassel, a mathematician and astronomer by himself. Although now forgotten he was an outstanding astronomer, his observations, particularly those of the fixed stars, were at least as accurate as those by Tycho Brahe. Bürgi was brought to the court to develop scientific instruments, and assist in the observation that could confirm the heliocentric model by Copernicus. He built various instruments. In 14th April 1586, the count wrote to Tycho Brahe about a highly accurate clock which Bürgi had built which, for the first time, had a minute hand, a seconds hand and had an error of less than a minute in 24 hours! Christoph Rothman, another astronomer wrote about the new amazing clock:

“The duration of a second is not very short but resembles the length of the shortest note in a moderately slow song.“

This quote commemorates a time when science and technology produce a new reality.

Bürgi precision clock

Epilogue

I read today about a new exhibition of Christian Boltanski in the Israel Museum called “life”. He wrote: [my translation from Hebrew]

“a major part of my job is the fact that each person is special, one-of-a-kind and important, each will finally vanish. Most of us will be forgotten in two generations, with the passing of those close to us. “

It’s certainly not true for al-Jazari but probably true for most of us. The exhibition combines early works of Boltanski alongside new works and includes a digital timer continually counting the seconds from the moment of birth of the artist. I found a photo of a timer installation of Boltanski at the Biennale. I don’t know if the installation in the Israel Museum is identical.

Christian Boltanski, the Venice Art Biennale, 2011.

 

 

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The automaton of a slave girl holding a glass of wine and slaves in the Artuqid Palace

Introduction

It is a decorated wooden cupboard by the king’s side during the feast. It has a door with two closed leaves. Every seven and a half minutes the doors would open and reveal an automaton (a mechanical device made in imitation of a human being) of a slave girl holding in her right hand a glass filled with wine and in her left a small towel. The king takes the glass, drinks the wine it contains, puts the glass back in her hand and, if he wishes, wipes his mouth with the towel. Then he closes the door leaves on her.  This process will repeat itself every eighth of an hour.

We met slaves and slave girls here and here(in Hebrew), but a quick search of the” Book of Knowledge of Ingenious Mechanical Devices ” reveals ten different chapters mentioning slaves or slave girls. This seems a lot! I went to study slaves in the Islamic world in the twelfth century and how similar or different it is from al-Jazari’s book. To my surprise, my journey led me to Cairo Geniza.

Automaton of the Slave Girl, Serving a Glass of Wine”, a folio from Syria or Iraq, 1315

How does it work?

The technical explanation, as always, will be colored in blue, so anyone who is not interested in an inclined plane or a tipping bucket can skip those bits. To understand the mechanism, I use a drawing by the book translator Donald R. Hill with my captions. The slave girl became a boy? I guess Hill or his illustrator did not think that gender was important?

A drawing of the mechanism by Donald Hill with my captions

The cupboard is about 1.6 meter (originally six spans, in Arabic شبر or shabr) and width of approximately 60 cm. There is a wine reservoir above the cupboard which is dripping slowly to the tipping bucket below. I already discussed the tipping bucket here. The tipping bucket fills in seven and a half minutes (eighth of an hour) and discharges all at once into the glass in the slave-girl’s hand. The glass becomes heavy enough to lower the hand of the slave which is on an axis, lifting the extension rod from the docking station.

The slave-girl will roll down the inclined plane and pushes the left leaf with her left hand, which is holding the towel like she is offering the wine glass to the king. The king takes the glass from her hand, drinks its contents, and if he wishes, wipes his mouth with the towel. Then he puts the glass back in her hand, presses it down, and pushes the slave girl gently until she docks. This process will repeat itself every seven and a half minutes as long as there is wine in the reservoir.

Slaves and girl slaves in the “Book of Knowledge of Ingenious Mechanical Devices “

In ten chapters of the “Book of Knowledge of Ingenious Mechanical Devices “ slaves are mentioned:

  1. Category I, chapter seven – The candle clock of the swordsman(Hebrew): An automaton of young black (غلام),  with no beard holding a sword to shorten the candle wick.
  2. Category  II, chapter three – An arbiter for drinking parties: An automaton of a young a slave girl ( (جَارِيَة‎) in Wikipedia also a concubine)  with a  bottle and a glass as well as four slave girls in the balcony.
  3. Category II, chapter four –The musical boat: An automaton of a musical boat with a slave holding a jug and goblet, and four slave girls, flute-player, a harpist and two tambourine-players. I believe that they are “qiyan” – educated girls and women who entertained and entranced the caliphs and aristocrats. I already wrote about them here (in Hebrew)
  4. Category II, chapter seven – A slave holding a Fish and a Goblet: An Automaton of a young slave pouring wine
  5. Category II, chapter eight – A man holding a goblet  and a bottle: An automaton of a slave pouring wine into a goblet
  6. Category II, chapter ten –A slave girl emerges out of a cupboard with a glass of wine: (The current post) Automaton of a slave protruding from a cupboard with a glass of wine.
  7. Category III, second chapter- al-Jazari’s motivation to make the automatic pitcher is written explicitly: ” King Salih, may God double his righteousness, disliked a servant or slave-girl pouring water on to his hands for him to perform his ritual ablutions and he wished me to make [something] for pouring water onto his hands for his ritual ablutions.”
  8. Category III, third chapter – A  slave who pours water over the king’s hands: An automaton of a  slave who pours water over the king’s hands.
  9. Category III, ninth chapter – A basin of the peacock for washing the hands (Hebrew): Automaton for washing, one with soap, the other with a towel
  10. Category III, chapter ten- A basin of the slave for washing the hands: An automaton of a kneeling slave holding a water pitcher in his right hand

Cairo Geniza and slavery in the twelfth century

Do we know who were the slaves and the female slave? How they were enslaved and what kind of life did they have?

Cairo Geniza (storage) is a large collection of Jewish manuscripts and fragments written between the ninth century and the nineteenth century and preserved in the attic of the synagogue in Fustat or old Cairo. Maimonides, while in Cairo, used to pray in this synagogue, and it is therefore also known as the Maimonides synagogue.

In my ignorance, I thought the Geniza was for damaged Bibles and holy books but apparently because the Hebrew language was considered sacred they saved everything: court documents, bills of sale, and the correspondence of the local Jewish community and more. Craig Perry wrote his doctoral thesis: “The Daily Life of Slaves and the Global Reach of Slavery in Medieval Egypt, 969-1250 CE” based on materials from the Cairo Geniza. This is not the story of the slaves in Diyarbakir palace where al-Jazari worked, but we can learn a lot.

In an undated letter from the Cairo Geniza, a local court in the Red Sea port of Aydhāb (today in Sudan). Two slave women appeared before the Qadi (Muslim judge), one of them testified that they were kidnapped when they went to fetch water at a local well and sold into slavery. The Qadi asked if they were Muslims? Because according to Islamic law, Muslims were ineligible for enslavement. One of the two insisted that she was Jewish and therefore the case was transferred to a Jewish court. The writer of the letter asked for advice from Fustat about how to handle the matter. His decision to consult with associates explains how this document came to be preserved in the Genizah. We don’t know what happened to the unfortunate women but this is an example of how women were enslaved, and there is a wealth of information about buying and selling of individual slaves.

The second way I already mentioned (in Hebrew) is diplomatic exchanges: for instance, the Egyptian historian Al-Maqrizidescribes  large processions of male and female slaves arrived in Cairo from regions to the south, the first one at 1023 CE:

“On Tuesday, when eight days remained in the month the gift of Ibn

Makārim b. Abū Yazīd arrived from Muḥdathah in Aswān, and it was:

twenty heads of horses, eighty fine camels, a number of black [slaves], females and males, a cheetah in a cage, Nubian goats, birds, monkeys and elephant tusks. “

Prestige gifts of slaves were not limited to Nubia. The Fatimid Caliph al-Mustanṣir Billah received gifts of Turkish slaves from the Byzantine emperor Michael IV, slaves, and eunuchs from the Amir of Yemen and slaves the ruler of al-andalus(الأندلس), the Muslim kingdom of Iberia.

The near constant warfare at the edges of the Islamic empire produced a steady supply of prisoners-of-war and  “wholesale” slave trade.

We don’t know if the slaves in the Palace in Diyarbakır came as a gift from another ruler, purchased individually, or captured during a war.

The bills of sale contain a wealth of information that is useful for reconstructing the geography of slavery, Allowing Perry to do the statistics on the origin of slave girls, horrifying as it may sound. Perry found a large majority of Nubian slaves along with quite a few slaves from other sources:

It is impossible to know, of course, the origin of the slaves in the Palace in Diyarbakır but the Geniza documents cover slave trade in the entire Middle East, and it is reasonable to assume that that is was not very different.

When I think of slaves, I think of hard work in the cotton fields or the sugar plantations in South America. The Islamic world of the 12th century was not associated with large-scale agricultural production. The use of domestic slaves reflects the relative wealth and urban nature of the Muslim elite. Families of merchants, judges, scholars, and others were able to purchase slaves to help with raising the children and household chores. This is evident from the Geniza and is very similar to the book of al­-Jazari. All the slaves in the book are part of the Palace household, helping with daily tasks or helping during the feast.

Slave women were frequently used as child-bearing concubines by Muslim men. According to Islamic law, children born to a Muslim master and a female slave were free-born Muslims. The Fatimid  Caliph al-Mustanṣir Billah, already mentioned, was the son of Sudanese slave named Rasad. That was not the situation in the Jewish community where the Rabbinical establishment struggled to deal with the phenomenon, but that’s another story. I completely Ignored the topic of slave soldiers. This is essential to the history of the twelfth century but is not part of al-Jazari’s book.

Epilogue

My deep connection to al-Jazari makes me want to apologize on his behalf because of the casual manner in which he relates to slavery. It is more painful due to human rights situation in Israel and the general feeling that human rights are under attack.

This is childish; you can’t throw me and the education I received at home and in  “Hashomer Hatzair” (a Socialist-Zionist, secular Jewish youth movement) to the 12th century. While I was searching for information on slavery I found  a text by Benjamin of Tudela  which for me was always just a happy song  (in Hebrew) by “HaGashash HaHiver”, an iconic Israeli comedy trio:

” And from there (Aden) to the region of Aswān is a journey of twenty days through the desert. This is Sebā on the Nile River that descends from the land of Kush. There are some among the Kush who have a king and they call him the sulṭān al-ḥabash. There is a people among them that are like animals that eat the grasses that grow on the bank of the Nile and in the fields. They go about naked and lack the intelligence of human beings. They lie with their sisters and with anyone they wish. (Sebā) is very hot. When the people of Aswān go raiding in their land, they carry with them bread, grain, raisins, and figs. They throw this toward (these people), who come to get it. They obtain many prisoners and sell them in Egypt and all of the kingdoms around them. These are the black slaves, the sons of Ham.”

This is more documentation (?) of capturing slaves in Nubia, but the reference to slaves is chilling and I’m afraid that it tells more about Benjamin of Tudela and his lack of ability to see another human suffering then it tells about the poor enslaved Africans. I would like to conclude with a line from the Universal Declaration of Human Rights:

“All human beings are born free and equal in dignity and rights. They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.”

universal declaration of human rights, December 1948

 

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

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

Introduction

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

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

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

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

How does it work?

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

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

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

Also:

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

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

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

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

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

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

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

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

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

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

Drinking habits in the twelfth century

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

The passing of time and great truths

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

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

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Al-Jazari and Versailles Fountains

Introduction

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

Versailles Fountains, unknown photographer, Wikipedia Commons

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

Combined Drawing, Six Fountains, Topkapi manuscript, 1206

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

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

    Tilting pipe, First Fountain, Topkapi manuscript, 1206

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

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

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

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

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

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

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

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

Nicolas de Fer, 1720, Marly Machine

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

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

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

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

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

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

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

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

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

 

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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.