The 1930s

Art Deco shapes, cases under 30mm, and an industry ten years into learning how to keep water out.

The decade the wristwatch won. By 1930 American shops were selling fifty wristwatches for every pocket watch, and the industry spent the next ten years solving water: Rolex had patented the Oyster in 1926, but by the early 1940s more than fifty rival waterproof case constructions were in circulation, including the screw-sealed Clamshell the Schmitz brothers patented in Grenchen through the 1930s. Cases rarely passed 30mm. Art Deco set the shapes — rectangles, tonneaus, and the curved cases built to follow the wrist — and production was tiny: Cartier did not make a thousand watches in a year until the 1960s.

These are the hardest of my watches to buy well and the easiest to buy badly. Survival is the whole question. A ninety-year-old case has usually been polished at least once, plating wears through at the lugs and corners first, and movement parts are genuinely scarce rather than merely inconvenient. Rarity here is real — fewer than a hundred Cartier Tank Cintrées left the workshop in 1928 — but rarity is not the same as value, and I would rather sell you an honest common watch than a rare one that has been rebuilt. I say which is which.