The advent of the railway in the 19th century necessitated a way to track accurate time across an entire continent—a need that resulted in the creation of time zones. In 1885, Swiss watchmaker Emmanuel Cottier devised an early mechanical movement that could be used to track the time simultaneously across multiple zones. His son, Louis, would perfect it into the “world timer." Beginning in the 1930s, he created pocket watches and wristwatches for Patek Philippe that used an ingenious “city ring" and 24-hour ring to show the time around the world. Primarily available to dedicated clients with deep pockets, these exquisite, precious-metal timepieces sometimes featured beautiful, richly colored enamel dials depicting a map of, say, Eurasia or North America. It was the reference 2523, however, launched in 1954, that truly launched a world-time revolution.
The 2523, unlike earlier world-timer iterations, used a smart dual-crown system: While the 3 o’clock crown was used to wind and set the movement, the 9 o’clock crown controlled the rotating city and 24-hour ring. Out of the way of one’s hand, this crown was less prone to being knocked about, reducing unnecessary wear on the bezel and maintaining an accurate picture of time around the world. Featuring a printed (rather than engraved) city ring, this highly legible watch was powered by the modified, manually-wound caliber 12-400 movements, around 45 of which were delivered. Incredibly low production estimates mean that the 2523, in the right configuration, is a multi-million-dollar watch at auction. Thankfully, however, Patek Philippe continues to make modern versions.
From the article by Allen Farmelo, Paige Reddinger, Victoria Gomelsky, Oren Hartov, Blake Buettner
