National Geographic : 1947 Sep
Split-second Time Runs Today's World 409 Staff Photographer Robert F. Sisson Just Before the Train Leaves, Conductor and Engineer Compare Watches This is a last-minute ritual on all American railroads. Only watches which have been examined and certified by company inspectors are used. They are checked against standard clocks and must keep accurate time within 30 seconds a week. Railroads instituted standard time for the United States in 1883 (page 411).