Abu Zayd Abd al-Rahman al-Ladjai

Abu Zayd Abd al-Rahman al-Ladjai was an accomplished mathematician, astronomer, and clockmaker (muwaqqit) in Fez. Commissioned by Marinid Sultan Abu Inan Faris, al-Ladjai designed and completed the famous hydraulic clock of Dar al-Magana on May 6, 1357, on the Tal'a Kebira.

This ingenious mechanism utilized water weights, release levers, and rolling brass balls that dropped into twelve bronze bowls every hour while opening wooden shutter windows, a masterpiece of medieval Moroccan mechanical engineering.