German watch journalist Gisbert Brunner writes in his co-authored book "Wristwatches Armbanduhren Montres-bracelets" (published in Cologne, Germany in 1999): "Not long ago, it was a natural daily routine to wake up in the morning, wind your watch, set the hands, and then put it on. This constant contact with your watch had become a kind of ritual, but the Third Industrial Revolution brought an abrupt end to this old habit for many people, with the introduction of electronic technology in timekeeping and the invention of the quartz wristwatch." It can be said that the highly accurate and hassle-free quartz watch has certainly changed the way people interact with their watches. Meanwhile, mechanical watches still require winding the mainspring and manually setting the hands to the correct time, just as they did back then.
The prevailing theory is that mainsprings, which are metal springs wound into a coil, first began to be used to power mechanical clocks in Germany in the 15th century. The mechanism of driving gears using the force generated by the unwinding of a wound mainspring already has a history dating back six centuries. The use of such mainsprings instead of falling weights led to a revolutionary advance in the miniaturization of power units, paving the way for portable clocks. The earliest famous mainspring-driven clock is the oval drum clock (commonly known as the "Nuremberg Egg") made by German clockmaker Peter Henlein around 1500. It is said to have run for 40 hours after being fully wound, making it an impressive piece of equipment for its time.
