The trench watch

A trench watch is a wristwatch of the First World War era, often a small pocket watch adapted for the wrist, made because pocket watches were impractical in combat.^1, 2

Typical features were wire lugs for a strap, hinged front and back covers carried over from pocket watches, white enamel dials with large numerals, radium-painted luminous hands and numerals, and an unbreakable crystal.^1, 3

Some carried a shrapnel guard, a pierced metal grille over the glass; the Smithsonian's Carlene Stephens told NPR it protected the tender dial in the field.^1, 5

Many trench watches carry no maker's name, only 'Swiss' on the movement; their movements often derived from ladies' pendant watches of the 1890s.¹

Radium dials lost their glow in three or four years, and surviving dials should be treated as radioactive.^1, 6

The Science Museum Group's example, lent by the Clockmakers' Company, is an Ingersoll 'Sterling' pocket watch in a Dennison case hallmarked 1915, with lugs added at 12 and 6; its luminous numbers were possibly added during the war.²

NPR reports that the Smithsonian holds an Elgin wristwatch of 1917 with a shrapnel guard, the kind many American officers wore.⁵

The Australian War Memorial holds a silver wristwatch of about 1914 given to Cyril Brudenell Bingham White, chief of staff of the Australian Imperial Force, by his sister-in-law and worn by him throughout the war.⁷

Retailers sold them to officers as kit. A London advertisement of 1918 offers the Goldsmiths & Silversmiths Company's 'Military' Luminous Watch, a silver screw case with a hunter or half-hunter cover, 'indispensable for Naval or Military Service', at £4 5s 0d or £4 12s 6d.⁸

Officers usually bought their own; from 1917 the British Army issued a limited number with luminous dials and the broad arrow, mainly to signals personnel and engineers, after testing Swiss watches and preferring screw-back cases by Dennison or Borgel.^3, 9

The trench watch is not 'the first wristwatch'. Wristlets for women are much older, men's military wristlets predate 1914 (Garstin's patent of 1893, Mappin & Webb's campaign watch advertised from 1898), and the 1880 Girard-Perregaux naval order is disputed.^9, 10

The name 'wristlet' gave way to 'wristwatch' in the early 1930s, by Wikipedia's account.¹