TATLER FOCUS 

There was a time when all watches came with a key. Look at the history books of brands that date back to the 18^th or 19^th century, and you will notice that many pocket watches or grandfather’s clocks had a round hole on the dial. This is where the key would go. The owner of the timepiece is required to wind the watch’s mainspring with this key every day or every other day.

 It was not until the early 1800s that keyless winding was invented by Jean Adrien Philippe, one half of the founding members of Patek Philippe. Instead of winding the movement by a key, Philippe created a watch that had the key perpetually attached to the movement—it was basically the crown.

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So this component now had two uses: to set the time and wind the movement. Simply by gearing the crown stem to a winding mechanism connected directly with the barrel, he made a movement that the wearer could quickly and conveniently wind. This obviously predates the invention of the self-winding mechanism but it’s worth noting that winding the movement via the crown is possible even with self-winding timepieces.