The Muslim engineers of the Middle Ages were known for their wildly creative machines, such as intricate clocks with many moving parts, simple robots that played tunes and pumps to displace water (more details in later posts)
In 803 AD a delegation of Arabs arrived in Germany to meet with Charlemagne with gifts from Caliph Harun al-Rashid. One of the gifts was a water clock that chimed every hour. The Europeans had never seen anything like this before! Some of the people at the court thought it operated on satanic magic, but after inspection they concluded:
‘[It is a] marvelous mechanical contraption in which the course of the twelve hours moved according to a water clock, with as many brazen little balls, which fell down on the hour and through their fall made a cymbal ring underneath. On this clock there were also twelve horsemen who at the end of each hour stepped out of twelve windows, closing the previously open windows by their movements'.
"The Great World History Book"