In our kitchen is a digital clock that is always almost perfectly on time. It listens to broadcasts of the time signals from the National Institute of Standards and Technology whose master clocks are among the most accurate in the world. Before we had this clock, I imbued my watch with the perfect time by going to the NIST website. Before computers, I would listen to shortwave broadcasts of the time signal, or of the famous on-the-hour pips from the BBC World Service. That's as far back as I go, but of course people have had to get their clocks set right ever since the sundial age. There's a wonderful little story of how they did it in London in _Ruth Belville: The Greenwich Time Lady_ (National Maritime Museum, Greenwich) by David Rooney. Rooney is a curator of timekeeping at the Royal Observatory in Greenwich and is an expert in the history of timekeeping. He also seems a relentless researcher, tracking down train and tube timetables, for instance, in order to tell his tale. It is a perfect blend of a social and technological history, a tiny slice of each with much bigger implications.
As befits a Greenwich timekeeper, Rooney gives us a short history of timekeeping at the Royal Observatory. If you were not close enough to the Observatory to keep its time, you might also not be able a watch around to Greenwich to be synchronized, but you might pay for someone to do it. This was the niche that Ruth Bellville (and her father and mother before her) filled for years, delivering and selling the exact time to Londoners. Her father, an astronomer and meteorologist at the Royal Observatory, set up the time distribution service in the 1840s. He chose for the service's watch a pocket chronometer made in 1794 by John Arnold (and thus referred to by Ruth by the pet name "Arnold"). Ruth's was not an easy job, requiring many steps to take Arnold on its rounds, as well as using the new tube system and other public transport. Her useful and unique career continued until 1940. You would think that 1940 would be far too late for people to be subscribing to a carried-chronometer time service. There were actually alternatives many years before. By the 1930s, there was a signal from the Eiffel Tower, and electric line signals, and the time pips from the BBC. If you needed the right time, there were many different ways to get it.
And still Ruth Belville made her rounds and was paid for it. Part of Rooney's theme is that scientific and technological revolutions do not simply happen so fast that everyone changes to the new system in a day or even a year. "New technology doesn't just sweep aside old systems," he assures us. "They co-exist for far longer than one might expect." The subscribers to Ruth's service didn't need to have good electrical equipment or a licensed radio, they just paid, and Ruth knocked on the door every week with Arnold's data. Subscribers could see Arnold ticking away, they could check his weekly certification, and they could be reassured that this was the real, physical time. Ruth shared a few words, or maybe sat for a cup of tea, and there was no other synchronization service that could have done that. Still, when she wound up her service in 1940, there was no one who would take it over, and no need. It was widely thought that the lady announcer for the telephone speaking clock service was Ruth's successor; Rooney tells us all about how the competition was run to select "the girl with the golden voice" who might recite the time into the recording machine. Arnold ran until Ruth died in 1943; after serving almost a century and a half, it went into the museum of the London Clockmakers Company. It's a good end to an amusing and instructive story, a well-told combination of human and technological interest.