Railroad chronometers
Railroad chronometers (railroader's watches) were critical to the safe and correct operation of trains in the United States. A system, which relied on accurate timekeeping, called Timetable and Train Order was used to ensured that two trains could not be on the same stretch of track at the same time.
After a serious train accident in 1891 on the East Coast of U.S.A., caused by the malfunction of a railway agent's watch, the North American railroad industry charged their General Time Inspector Webb C. Ball to establish unified standards for all the watches used by their personnel across the various participating Railroad Companies:
- only American-made watches may be used (depending on availability of spare parts)
- only open-faced dials, with the stem at 12 o’clock
- minimum of 17 functional jewels in the movement, 16 or 18-size only
- maximum variation of 30 seconds (approximately 4 seconds daily) per weekly check
- watch adjusted to five positions
- indication of time with bold legible Arabic numerals, outer minute division, second dial, heavy hands,
- lever used to set the time (no risk of having the stem left out, thus inadvertently setting the watch to an erroneous time)
- Breguet balance spring
- micrometer adjustment regulator
- double roller
- steel escape wheel
- anti-magnetic protection
The Waltham Watch Company immediately complied with the requirements of Ball's guidelines, and soon did Elgin Watch Company and most of the other American watch manufacturers, applying the American System of Watch Manufacturing. Waltham became the official timekeeper of railroads in 52 different countries.
W.C. Ball's guidlines are the basis of the officially certified Chronometers standards, as now laid out by the "Société Suisse de Chronométrie", which was founded in 1924 and "The Swiss Official Chronometer Testing Institute" COSC ("Contrôle Officiel Suisse des Chronomètres").
