This interesting and less-than-five-minutes video is an excerpt from a full BBC documentary by Professor Simon Schaffer of Cambridge. It features "The Writer," a cam-guided, programmable automaton by Pierre Jacquet-Droz:
The writer is the most complex of the three automata. Using a system similar to the one used for the draughtsman for each letter, he is able to write any custom text up to 40 letters long (the text is rarely changed; one of the latest instances was in honour of president François Mitterrand when he toured the city). The text is coded on a wheel where characters are selected one by one. He uses a goose feather to write, which he inks from time to time, including a shake of the wrist to prevent ink from spilling. His eyes follow the text being written, and the head moves when he takes some ink.The full, hour-long documentary is here. A tip of the blogging hat to reader Alex O. for bringing the link to my attention.