The 240 Year Old Pendulum Clock That’s More Accurate Than your Watch
It was this crisp reasoning that prompted the designs for Clock A, a super exact pendulum clock, being acknowledged by clockmaker Martin Burgess.
Clock A was commissioned from Burgess in 1975 by the Gurney family, a Norwich banking family. Completed in 1987 (demonstrating you can’t surge great clockmaking) they gave the clock as a blessing to the city of Norwich where it presently ticks cheerfully in a neighborhood retail outlet, the Castle Mall. Burgess had likewise begun another Harrison pendulum clock, Clock B, but not completed it. The parts for the clock accumulated residue on a rack in Burgess’ workshop until 1993.
In 1993, he conveyed a paper at a Harvard horology conference where he discussed the ‘scandalous neglect’ of Harrison’s work in pendulum clock development – and, critically, referenced Clock B. Workmanship history specialist and clock authority Donald Saff read the paper, found him and convinced him to sell him the unassembled and incomplete Clock B. Saff at that point commissioned English clockmaker Charles Frodsham to complete the project.
Once the clock was completed in 2014, it pulled in such a consideration from horologists that chief class footballers would be acquainted with. The began considering the clock in March 2014 and how it worked…
It immediately became evident that Clock B was something exceptional to be sure. McEvoy proceeds, “We took a gander at the behavior of Clock B profoundly, and we found that any changes in its timekeeping were repetitive. All in all, they weren’t a problem because they were completely predictable.” So albeit the clock’s timekeeping shifted by a couple of parts of a second, basically, it leveled itself out.
Finally, to decide if Harrison’s words were surely “…the indications of insanity” as The London Review of English and Foreign Literature proposed, Clock B was fixed in a perspex case in January this year and tested for 100 days.
To guarantee there was no horological dabbling, the National Physical Laboratory and Worshipful Company of Clockmakers directed the preliminaries. Toward the beginning, Harrison’s B clock was running a quarter second behind GMT. Following 100 days of running, it was a simple 5/8ths of a second behind.
Guinness World Records have affirmed Clock B as the “most precise mechanical clock with a pendulum swinging in free air.” But that bald portrayal downplays the accomplishments of both Harrison and Burgess. This is a clock that is so exact, its caretaker had the option to quantify the effect of barometric tension on its going. “As the barometer went up, so the clock eased back down with air density,” clarifies Rory McEvoy. ‘When we changed the clock to consider barometric pressing factor, it was 96% precise. On most clocks, you wouldn’t even notification the mistake, not to mention be able to address it. We don’t see such a precision until in any event 150 years after Harrison’s death.”
You’d believe that with pin-sharp exactness like this, Clock B would be a horological diva, pitching timekeeping fits on the off chance that it was halted or begun. But not really, says McEvoy, “Once it’s changed, Clock B is remarkably stable. You can pause and begin it with no problems.”
So for what reason did Harrison do it? For what reason did he persevere until practically the day he kicked the bucket in creating, safeguarding and advancing pendulum clocks? He had a dream that, at some point, each port would have a public pendulum clock, precise to inside parts of a second, for sailors to set their marine chronometers by. This would mean they had the option to ascertain their situation adrift to inside a couple of nautical miles, hence missing reefs, sandbanks and rocks. Harrison understood that precise timekeeping wasn’t simply a hypothesis, it was a lifesaving practice.
So, one year from now, on the 24th of March, raise a glass to Mr Harrison’s 240th commemoration. A remarkable man especially relatively revolutionary. This year, go on an outing to Greenwich and investigate Harrison’s other remarkable marine chronometers – it’s definitely justified even despite the visit.
——— Notes and extras
The hypothesis behind the clock captivated a gathering of horologists, specialists and clockmakers who became The Harrison Research Group (HRG), meeting once every year. As Rory McEvoy, Curator of Horology at Greenwich puts it. “The work of the HRG finished in this commonsense endeavor to demonstrate Harrison’s hypotheses were valid.”
for more on Clock B and John Harrison, check out: Frodsham.com