An automatic (or self-winding) watch is fitted with a device (rotor) that automatically winds the spring by using the force of gravity. It needs no battery, but it will stop if you have been physically inactive for an extended period of time--as long as you're moving, the watch will stay powered. Swiss watchmaker Abraham-Louis Perrelet invented the self-winding mechanism in 1770. It worked on the same principle as a modern pedometer, and was designed to wind as the owner walked.
About Cartier Watches While Cartier is well known for its majestic jewelry, but the House of Cartier--founded in 1847 by Louis-Francois Cartier--is also world-renowned for its luxury timepieces and wristwatch innovations. In 1910, Cartier created the deployment folding clasp, which is now used by watchmakers around the globe. In 1917, the Cartier Tank Francaise was introduced, amd is today considered a classic example of style and design. Modern Cartier watchmakers still base their watch designs on the early fundamentals developed by Louis Cartier.