Since about 1800, maritime navigation has relied on super-accurate timekeeping. Recently this has involved radio time signals beamed down from Global Positioning System (GPS) satellites, but for the bulk of the period, ship masters have navigated using the chronometer. These are very accurate portable timekeepers carried on the ship, providing a reference to compare against local time.
The difference between the two times is equivalent to the east-west distance between the two places. That’s longitude, and it was a real devil to find before the chronometer was developed. One of the most notable chronometer-making firms celebrates its 175th birthday this year. Founded in 1834, the Charles Frodsham company is still going strong today.
Back in the day, they worked in partnership with the Astronomer Royal at the Royal Observatory, Greenwich, on high-tech timekeeping research projects that saved countless lives at sea. About to go back on display in our newly-refurbished Measuring Time gallery is this top-quality example of Charles Frodsham’s early work – a lovely 1840s pocket chronometer:
Now, they’re developing a new form of mechanical wristwatch which will be built entirely at their premises in Sussex. I visited them last week. Their skill and passion is remarkable, blending old-school watchmaking skills with the latest sophisticated design processes and highly complex mechanical manufacturing methods. We’ve always been good in this country at technical design and innovation, and I saw no end of that out in Sussex last week.
Happy 175th birthday!


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