The First Machines You Could Program — the Banu Musa + al-Jazari

What you'll learn

• The Banu Musa ("sons of Musa") — Muhammad, Ahmad and al-Hasan — worked in Baghdad in the 9th century and wrote the Book of Ingenious Devices (about 850): about 100 clever machines, like trick jugs and fountains.
• They also described a water-powered flute player whose tune was set by pins on a turning drum: a pin works a lever, the lever opens a hole on the flute, out comes a note. Swap the drum = a new tune — one of the earliest known programmable machines.
• al-Jazari, engineer in Diyarbakır (now Turkey), finished his Book of Knowledge of Ingenious Mechanical Devices in 1206: 50 machines with drawings and step-by-step notes.
• His elephant clock: a bowl with a small hole floats in water inside the elephant and sinks in half an hour; it pulls a string, a ball drops, the figures move — then it starts again.
• His boat of robot musicians: the drummer's beat came from pegs on a turning wheel. Move the pegs = a new rhythm.
• The same idea came back in music boxes, in the Jacquard loom (1804, punched cards set the pattern) and in early computers (programs on punched cards: hole or no hole = 1 or 0). Your phone does it with billions of tiny switches.
• Episode 2's challenge: lift the candle, and its picture on the wall moves DOWN — the rays cross in the hole, so everything flips.