Notes on the Western Union Telegraph Clock (FoRK mail list archives), about accurate time being sold for one dollar, per clock, per month. And Time, Standard Time and Western Union goes into some of the daily life specifics of a centralised clock world: Railroad workers were required to carry an approved pocket watch and correct it on the hour when the Morse signal came through.
But sometimes it went wrong: "It finally ensued that I learned the magic of WUTCo clocks was a 'Master Clock' in each local area. It ran like an old schoolhouse clock with a punched paper tape to ring the bells -- except that a WUTCo local master clock had only one set of holes at the top of the hour. When it ran past the holes, it sent a two-second pulse down a local telegraph loop with all the clocks around town wired in series like teleprinters. [...] The way the synchronization operation worked was that in each local area, it was the distinct 'job' of the Wire Chief to be there at noon daily, to get a 'click' on the sounder of one national wire, and set their local Master Clock to the once-a-day time from the national 'click.' However, at Fort Lauderdale, the Wire Chief had been promoted out of town TWO YEARS previously, so it was nobody's job to set the local Master Clock".