Swiss watchmaker Henri-Louis Jaquet-Droz was a genius with clockwork. He did not confine his efforts to timepieces, but also constructed automata -- clockwork robots. The most famous of these are three automata known as the Jaquet-Droz Automata, constructed between 1768 and 1774 in collaboration with his father Pierre, who owned the family business and oversaw the project, and brother Jean-Frédéric Leschot.
Astonishingly, the purpose of these marvels of gears and springs was not invention and ingenuity for their own sake, or even to be follies purchased and enjoyed by the wealthy. They were to demonstrate the clockmaking skills of the Jaquet-Droz family, as an advertisement to sell watches.
The three automata, which still function today over 240 years later, perform different tasks.
The Musician, the figure of a fine lady, plays music by pressing the keys of a custom-designed keyboard with her fingers. She moves her head, looking around, and lowers her gaze, leaning her body forward at times with the music. Her chest expands and contracts, as though she is breathing. Over 2,500 pieces went into her construction, and the five pieces of music she plays were composed by Henri-Louis Jaquet-Droz, who was something of a polymath.
The Draughtsman, the figure of a young boy, draws pictures, "programmed" with four designs. With his pencil, he can draw a dog, a portrait of Cupid in a chariot, a portrait of the French king Louis XV, and a portrait of the royal couple, Louis XV and his wife Marie Antoinette. It is made of 2,000 pieces, and the arm is controlled by cams that direct the arm to draw the pictures. A small bellows in the chest of the automaton allows it to occasionally blow the pencil dust off the paper.
The Writer is the most complex of the three, coming in at 6,000 pieces. It operates like The Draughtsman, with a system of cams controlling the arm and hand holding a quill. The boy dips the quill in an inkwell and shakes off the excess before putting it to paper. The reason The Writer is more complex is that it can write any custom text up to 40 letters long. These letters are programmed via a wheel, where you can input them one by one, with 40 separate cams controlling each letter. His eyes also move, following his pen as he works.