In 1929, watchmakers in Switzerland at the company Jaeger-LeCoultre created the Calibre 101. It is the smallest mechanical watch movement in the world - about 14 millimeters long, 4.8 millimeters wide and 3.4 millimeters thick. That’s smaller than the nail on your pinky finger.
What makes it special is that it isn’t a quartz watch run by a battery. The Calibre 101 is fully mechanical, with 98 tiny gears, springs and screws all working together. Some of those parts are so small that watchmakers have to handle them with tweezers under a microscope.
Famous people have been wearing this watch for almost 100 years. Queen Elizabeth II wore one to her coronation in 1953, and the same watch is still ticking decades later. Most other tiny gadgets get tossed when they break, but a Calibre 101 can keep running for a lifetime - or even two.
