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.

The Monk Basin and Bloodletting

Introduction

Bloodletting was common among many ancient cultures: Greece, Egypt, and Mesopotamia. Islamic medicine preserved and developed the medical knowledge of the classical period and the main traditions of Hippocrates, Galen, and others including the practice of bloodletting. Al-Jazari designed four apparatus for measuring the quantity of blood drawn. Al-Jazari devices are unprecedented and resemble water clocks and automata rather than medical tools.

The Monk Basin for measuring amount of blood during bloodletting.

How does it work?

The monk basin mechanism is quite similar to the mechanism of the Water Clock of the scribe. I bring the original drawing of the mechanism in parallel to the drawing made by Donald R. Hill, The book translator with my captions. 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 monk is standing in the center of the basin with a flat rim. He holds a staff in his hand pointing downward. The rim is numbered between 1 and 120 dirhams (درهم) about 360 milliliters. The monk is positioned on the main pulley which is attached to two ropes through two small pulleys. On one end there is a float and the other is attached to a balancing weight. Before the beginning of the bloodletting, two dirhams of water (approximately 6 milliliters) are poured for two purposes:

  • It wets the walls and reduces surface tension so that blood flows more smoothly
  • It sets the float to the starting point and zeros the staff position.

As bloodletting begins, the blood flows through the holes into the reservoir. As a result, the float goes up and releases rope through the pulley, the weight continues to pull down, and the large pulley rotates with the monk staff indicating the amount collected so far.

 

Bloodletting

Bloodletting was a common medical treatment in ancient times, but it received substantial reinforcement from Galen, the Court physician of the Roman Emperor Marcus Aurelius. Galen’s understanding of anatomy and medicine was influenced by the then-current theory of humorism, also known as the four humors – black bile, yellow bile, blood, and phlegm.  Excess of black bile was understood to cause depression or melancholy. Phlegm, or mucus, was thought to be associated with a low level of energy and emotion, as preserved in the word “phlegmatic.” Yellow bile was connected to aggression, but Glen believed that blood is the dominant of the four. It was assumed to be produced exclusively by the liver and was associated with enthusiastic, active, and social nature. To balance one temperament or health, Galen created a complex system that showed how much blood must be shed, based on the patient’s age, status, season, and weather. He believed that “excess” blood symptoms are fever and a headache. Bloodletting location was specific to disease: vein or intravenously, close or far from the affected body part. As the problem was more serious, more blood was shed. High Fever demanded enormous amounts of bloodletting. Galen theories dominated Western medical science for more than 1,300 years. Understanding the function of the heart and the circulation of blood was obtained by surgery of cadavers in the 16th century. Amazingly it didn’t stop the practice of bloodletting till the 19th century when significant evidence regarding the damage caused by the procedure was accumulated.

It’s interesting that you can still find the remains of Galen theory in our language – for example, melancholy is literally “black bile” in Greek ((μελας, melas “black”, χολη, kholé “bile”).  In the medieval time, Islamic medical knowledge was the most advanced in the world, it combined the knowledge of the ancient Greek, Persian traditions and the ancient Indian tradition of Ayurveda. Rebirth of Western medicine was based mainly on texts in Arabic. In addition to preserving the knowledge, there were significant advancements including initial understanding, at least in part, of the blood circulation by Ibn al-Nafis which pre-dates William Harvey, by ~ four hundred years. It did not help to stop the bloodletting.

Maimonides, Rabbi Moshe Ben Maimon, beyond being the most prolific and influential Torah scholars of all generations, was an exceptional philosopher and physician who wrote (surprisingly?) about alcohol, exercise, and hygiene in a way that fits our current medical information. He did not reject bloodletting but added a few reservations, probably from his experience:

“A man should not accustom himself to let blood regularly, nor should he do so unless he is in great need of it. He should not let blood in hot days or rainy days but in Nisan ( a month on the Jewish the calendar ~ March-April) and a little in Tishrei (the first month of the Jewish year ~ September) and after fifty (years) will not let blood. One will not let blood and enter the bath on the same day, nor will he let blood and go on a journey or in the following day. He would eat and drink less than he is used to and rest at the day of bloodletting.”

Mishne Torah (I could not find a proper translation to English, so this is a literal translation by me)

Al-Jazari and Bloodletting

Two things jump immediately:

  • The first is the device choice. It seems it would be much easier to measure the blood in a bowl or a vessel with scale than the extravagant solution al-Jazari chose. The next post on the “Basin of the Two Scribes” will elaborate on this point.
  • The second point is the monk. The fact that a Muslim engineer chose a Christian monk surprised me.

To the best of my knowledge of Islam, as a rule, does not support abstinence and seclusion and considers it a sin. The multinational society in Diyarbakir in the 12th century included Christians, was it the responsibility of monks to let blood?

I could not find any direct information, but in 1163 the Church issued a church order which forbade monks and priests from bloodletting, claiming the Church despises (no less!) the procedure. It was part of a ban on scientific investigation, so we cannot suspect the Church of medical progress. Since a decree was warranted, we can assume that this was rather common and the al-Jazari’s device is reflecting that. In response to the order, the barbers began to offer a variety of medical services including bloodletting, pulling teeth and even surgical operations like amputations. It is hard to imagine a haircut or a shaving following a surgery. The pole with stripes that mark a barbershop even today:

The barbershop pole originated from the practice of bloodletting in medieval days. The top bowl represents a basin for leeches, where the bottom bowl represents the basin where blood was collected. The striped pattern is red for blood, white for the bandages and blue perhaps for the veins (?) The last part is not very convincing, but I did not find a better one. There are claims that barbers used to hang bloody towels or bleeding bandages on the pole