LOCK, STOCK AND BARREL

Watch cases, though fundamentally adhering to the form-follows-function recipe, are as expressive of a timepiece’s identity as is the dial. Think of the bulge on the side of a Greubel Forsey, the U-shape of an Urwerk or the unique and iconoclastic case of the Hamilton Ventura. Tool watches naturally feature robust housings designed to protect the movement against whatever the specific tasks throw up as challenges. Whatever the role, everything about a case serves the manufacturer’s aesthetic dictum.

While the overwhelming majority of watches employ round cases, with square or rectangular types occupying the No 2 spot, the quiet sibling bringing up third place is the tonneau. Round is always round, varying according to whether or not it boasts shoulders to protect the crown, and lug shapes can vary according to needs or tastes. Square and rectangular cases by definition have four clearly defined corners, but the term “tonneau” is open to interpretation.