Pocket Watch

Overview

A pocket watch is a portable hand-wound mechanical timekeeper sized to be carried in a waistcoat or coat pocket on a chain. It packs the same elements as a longcase clock, a spring, a wheel train, an escapement, and a regulating oscillator, into a flat circular movement a few centimetres across. From the late 17th century until the wristwatch displaced it after the First World War, it was the standard personal clock, and the hunter style here adds a hinged metal lid that snaps shut to guard the crystal.

The watch is built from a handful of groups. The Movement is the caliber that keeps time; it is wound and set through the Keyless Works keyless works at the crown. The works are protected by the Case, whose bow lets the watch hang from a chain, and the time is read through the domed crystal on the Dial & Hands.

How it works

Turning the crown winds a flat mainspring inside the barrel. The barrel's torque feeds the going train, centre, third, and fourth wheels with their pinions, which steps the slow, strong rotation of the barrel up into the fast, light rotation needed at the escape wheel.

The lever escapement converts that steady drive into counted beats. A jewelled pallet fork alternately locks and releases the escape wheel, and at each release flicks a precise impulse through its roller jewel to the balance wheel. The balance, returned by its hairspring, swings to and fro at a fixed frequency; a movable index regulator tunes the rate by shortening or lengthening the spring's active coil. Synthetic ruby jewels at the heavily loaded pivots cut friction and wear. Pulling the crown shifts the sliding clutch in the keyless works from winding to hand-setting, engaging the setting wheels so the same crown can move the hands through the under-dial motion works that drive the 12:1 hour-to-minute reduction.