A tourbillon is a mechanical complication found in the movements of certain high-end mechanical watches. It is a mechanism that constantly rotates the balance wheel, balance spring, and escapement while the movement is running to counter the effect of Earths gravity on the isochronal properties of the balance wheel and spring. The tourbillon was invented by Abraham-Louis Breguet in 1795 and patented in 1801. The word "tourbillon" is a French term that means "whirlwind," which aptly describes its motion. It is mesmerizing to watch the balance wheel oscillate at the same time it is turning 360 degrees. Breguet sought to eliminate positional error, which is the error introduced by keeping the watch in one position for an extended amount of time. His theory was that if the regulating organ of the watch was constantly in motion, the positional errors would be averaged out.

Watches with tourbillons are usually more expensive compared to watches without them. They are not the most common complication that youll find on a watch, but certainly one of the most entertaining. Sometimes an unsavvy watch dealer might mistake a watch with a semi-skeletonized dial showing a visible balance wheel known as an "Open Heart" for a tourbillon. Thats why its important to contact a watch expert from a trustworthy company before buying it.

Today, the usefulness of a tourbillon is controversial, as a wristwatch is constantly being moved in different positions as it is worn. The tourbillon is often used as a display of watchmaking virtuosity, commanding high prices. High-quality tourbillon wristwatches, usually made by the Swiss luxury watch industry, are very expensive, and typically retail for tens of thousands of dollars or euros, with much higher prices in the hundreds of thousands of dollars or euros being common.

In summary, a tourbillon is a mechanical complication found in high-end mechanical watches that constantly rotates the balance wheel, balance spring, and escapement while the movement is running to counter the effect of Earths gravity on the isochronal properties of the balance wheel and spring. It is a display of watchmaking virtuosity and is often used to command high prices.