Cartier Tank à Guichets 2817

Is it a digital watch? No, it’s the Tank à Guichets: Cartier’s exemplary jumping hour mechanical wrist watch. Cartier’s boundless creativity is one of a myriad of reasons we have a soft spot for the maison. And few things exemplify that innovative spirit more than the Tank à Guichets.

We’re used to seeing hands glide across a dial to indicate the time on a watch. Yet, a little known complication from the late 1800s changed all that. The Austrian engineer Josef Pallweber came up with the ingenious idea of displaying time with the aid of moving discs that can be viewed through separate apertures.

This jumping hour complication began to be incorporated in watches by the likes of IWC, Jaeger-LeCoultre, and Patek Philippe during the 1920s. Yet, the most important and beautiful one is the Tank à Guichets that was introduced by Cartier in 1928. The Tank à Guichets (‘Tank with Apertures’) took the iconic Tank with its rectangular shape and elongated vertical brancards and completely did away with the dial. Presented as a solid block of metal, the time could be read through two apertures: one for the slow-moving minutes disc and one for the hour disc that jumped at the top of every hour.

The Tank à Guichets was such a curious little beast that no more than two dozen were ever made, though we know that it graced the wrists of remarkable individuals such as jazz icon Duke Ellington. As with many Cartier creations, the Tank à Guichets was relegated to Cartier’s annals until the maison re-released it as a three-piece set in 1996, a 150-piece platinum anniversary collection to celebrate Cartier’s 150-year existence in 1997, and, finally, a 100-piece rose gold Collection Privée Cartier Paris (CPCP) edition in 2005.

This ref. 2817 is one of those 100 rose gold pieces from the 2005 CPCP run. The watch features a 26 x 37 mm 18k rose gold case with a beautiful brushed finish all over. A rectangular aperture at the upper half displays the current hour, while an arc-shaped aperture below shows the sweeping minute disc. Meanwhile, in true Cartier fashion, the octagonal crown is topped with a blue sapphire.

This collectible and historically important Cartier is in excellent condition and comes with the original box, a black alligator leather Cartier strap and an 18k rose gold deployant clasp.