Al-Jazari's castle clock
Reloj del castillo de al-Yazarí
- Date
- 1206 · confidence high
- Place
- Diyarbakır, Türkiye
- Credited to
- Ismail al-Jazari
- Field
- Knowledge & symbols
What it is
A water-driven astronomical clock about three metres tall, described in his 1206 book, with a zodiacal dial, sun and moon indicators and figures that sounded each hour. It adjusted the length of day and night through the year, which is why it has been compared with a programmable analogue machine.
Only the description and the manuscript drawings survive; there are no remains. The label 'programmable analogue computer' comes from modern interpretations and is an analogy, not al-Jazari's intention.
What it led to
- automatic clocks with astronomical display in Islam and Europe
- cam and crank mechanisms in medieval engineering
- the automata tradition of the Artuqid court