Wristwatch by J. Harwood and Son; Blancpain, Switzerland, circa 1930

Record summary

Held and catalogued by Science Museum Group, London (object number 1958-263), this is a radioactive material; wrist-watch; self-winding watch by J. Harwood and Son; Blancpain, made in Switzerland, dated circa 1930. The Atlas places it in the Golden Age of Mechanical Watchmaking period (1900 – 1945) of its Wristwatches collection. The record is illustrated with 2 photographs.

Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.

Catalogue description

The source record does not include a narrative description. The structured fields above are reproduced from it.

Atlas type guide

Automatic (self-winding) watches

Self-winding watches use the wearer's motion to wind the mainspring. Abraham-Louis Perrelet and Breguet made 'perpétuelle' pocket watches with oscillating weights in the late eighteenth century, but the principle only became practical in the wristwatch. John Harwood patented a bumper automatic in 1923; Rolex's Perpetual rotor (1931) winding in one direction, and later bidirectional rotors (Eterna, Felsa Bidynator), established the modern form. Micro-rotors (Universal Genève, Buren) and peripheral rotors made automatic watches thinner.

General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.