Culture and history · How ideas travel

Al-Jazari: automata and medieval engineering

A book completed in Diyarbakir (Amid) in 1206 describes fifty devices with their measurements and drawings: the Elephant Clock, water-raising machines, musician automata. From the sinking bowl to the camshaft, explore al-Jazari's mechanisms and how much of the "first robot" claim is true.

18 min
2 simulations
Mini quiz

Updated: 22 October 2026

Preview

The question

A banquet at an Artuqid palace. Beside the table stands a metal elephant carrying a small tower on its back. When half an hour has passed, a ball rolls out of the tower, a serpent's head tips forward and the elephant's driver brings down his mallet to sound the half hour. Then everything quietly returns to its place, and half an hour later it all starts again. What was inside this Elephant Clock? And from whom had the master who designed it inherited his knowledge?

Try it yourself

No account needed: change the values and check your answer. Some simulations ask for a prediction before they start; it doesn't matter whether it's right or wrong.

Ordering

Half an hour in the Elephant Clock

Put the cards in order by dragging them or moving them with the keyboard, then press Check.

Predict first

Which part do you think really measures the time in the Elephant Clock?

It doesn’t matter whether you’re right; the simulation opens once you choose.

Matching

Device and principle

Choose a principle for each device, then press Check.

Predict first

Could a toilet cistern and an 800-year-old water clock share a working principle?

It doesn’t matter whether you’re right; the simulation opens once you choose.

Lab

Inside the Elephant Clock

Open full page in the Lab →

Fig. 1Inside the Elephant Clock

Drag the time, press Play or take the clock apart

Parts and the hidden mechanism

Apart0%

With the clock apart, hover over a part, tap it or pick it from the list; use the arrow keys to move through the list.

Pick an assembly to see what it does and what it is made of.

Time elapsed

Bowl fill time

Hole diameter: 1.00× the hole in the article

Time elapsed: 20.0 min
Bowl filled: 68%
Balls dropped: 0 / 8
Ball interval: 30 min

Water seeps in through the hole in the bowl’s bottom; as the bowl fills it sinks by the same amount.

Learn

Progress is kept on this page only; no points are given.

1Predict
2Try
3Explain

If you make the hole in the bowl’s bottom half as wide, how long does the bowl take to fill?

Gold: the balls, and the roundels that count the dropped ballsPurple: the tank water and the water filling the bowlThe cycle follows the order given in the article. The bowl is taken as a thin-walled cylinder: as the water inside rises, the bowl sinks by the same amount, so the pressure difference across the hole stays the same and the bowl fills at a steady rate. The flow through the hole then depends only on its area: when you change the fill time, the hole diameter is worked out as inversely proportional to the square root of that time, and the ball interval is the fill time plus the half minute of sinking and ball drop. Simplifications: the number of balls in the tower (8), how the strings run over pulleys, the seesaw gate, the bowl draining once lifted, and the pointer and roundels of the dial are illustrative; the article does not describe the original dial or sound mechanism in detail, and since accounts differ on whether the sound came from a cymbal or a drum, a drum is drawn here. During playback, time runs 177 times faster while the bowl fills (filling takes about 10 seconds) and 2.5 times faster during the sinking and the ball drop. The positions in the taken-apart view are only for display; the materials and decoration are a reconstruction, and the hole is enlarged in the cutaway so it can be seen.

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Frequently asked

5 questions

Did al-Jazari build the first robot?

No. In the 1st century AD Hero described a cart whose path was set in advance, and in the 9th century the Banu Musa brothers described a flute that played by itself. Al-Jazari is cited as an early example of programmable automata; his real contribution is a detailed, buildable and teachable account.

Where did al-Jazari live and when did he write his book?

He worked for twenty-five years in the service of the Artuqid rulers, whose court was then in Amid, today's Diyarbakir. He completed his book in 1206: it describes 50 devices with drawings, part measurements and building steps. His year of birth is only an estimate.

How did the elephant clock measure time?

A bowl with a small hole in its bottom floats on water; water seeps in and the bowl fills and sinks in about half an hour. Strings tied to the sinking bowl move the mechanism in the tower and start the show. A bigger hole fills the bowl faster, so the size of the hole sets the time.

What does a cam do?

A cam is a set of pegs on a rotating shaft. As the shaft turns, the pegs push and release levers one after another, so a smooth rotation becomes a repeated striking or lifting movement. The drumsticks of the drummer in al-Jazari's boat automaton rise and fall this way.

Were al-Jazari's devices just toys for the palace?

No. The book includes five water-raising machines for irrigation and water supply; one of them turns the rotation of a wheel driven by a stream into the back-and-forth motion of two pistons. The banquet automata were also a way of testing ideas about timing and control.