Railroad chronometers, or Railroad Standard Watches, are specialized timepieces that once were crucial for safe and correct operation of trains in many countries. A system called Timetable and Train Order, which relied on highly accurate timekeeping, was used to ensure that two trains could not be on the same stretch of track at the same time.
Regulations of the watches used by critical personnel on the railroads (engineer, conductor, switch yard controllers, etc.) were specified almost from the beginning of widespread railroad use in the 1850s and 1860s.[1] These regulations became more widespread and more specific as time went on, with some watches that were "railroad standard" in one time period falling away to no longer being qualified in others. There was no absolute, universal definition used across different railroad lines; each company appointed one or more "time inspectors" (typically a watchmaker) who decided which watches they would work on and accepted as usable. In the United States, the American Railway Association held a meeting in 1887, which resulted a fairly standardized set of requirements, [2] but not all railroads adopted them.
One notable watch inspector was Webb C. Ball. His first job as a time inspector was when he was brought in by the Lake Shore and Michigan Southern Railways in 1891 after a crash and was tasked with bringing their time inspection standards up to industry normals. Ball's career eventually led to him being the time inspector on more than half the United States' railways, leading to a far more uniform set of standards in the U.S.
A typical railroad's requirements for a watch in the early 1900s might include:
The Waltham Watch Company and the Elgin Watch Company were both used as early as the 1860s and 1870s [3] [4] as railroad standard watches. Later, Hamilton Watch Company, Illinois Watch Company and many of the other American watch manufacturers all produced railroad-grade watches.
The Time Signal Service of the United States Naval Observatory was used to ensure accuracy of railroad chronometers and schedule American rail transport.[5]
The minimum requirements were raised several times as watch-making technology progressed, and the watch companies produced newer, even more reliable models. By WWII, many railroads required watches that were of a much higher grade (as many as 23 jewels, for example) than those made to comply with the original 1891 standard. [6]