Although the longitude story is typically dominated by the development of marine timekeepers and the lunar distance method, we need to spare a thought for good old dead reckoning – estimating a ship’s position by regularly noting its speed and heading – which, even today, is part of the routine. This was certainly also true in the 18th and 19th centuries and so improvements to dead reckoning were of interest to the Board of Longitude, particularly once its remit expanded in 1774 to include general improvements in navigation. Among its archive, therefore, are quite a number of proposals to improve this most traditional form of wayfinding.
What’s a bit less common, however, is to have a surviving instrument, in particular relating to a proposal that was not taken up in any great way.
This one, from our collections at Royal Museums Greenwich (museum number NAV0730), is a log recorder – ‘Higginson’s Log’, as it says on the side – intended to record a ship’s speed by measuring the pull (against a spring) of a rope attached to a chip-log trailed behind the ship.
What’s nice is that we can link this instrument to a proposal from 1828 that survives in the Board of Longitude archive. The proposer, Francis Higginson, describes himself as the ‘inventor of a variety of instruments and the author of Manderville, Moubray, Waterloo etc.’. Of these, the only one I’ve identified so far is Manderville; or, The Hibernian Chiliarch, on the title page of which he also describes himself as ‘Late Commander of His Majesty’s Cutter Lynx’. This also tells us that he had been an insolvent debtor in 1825, when his petition was heard at the Court for Insolvent Debtors in Lincoln’s Inn Fields, London on 29 July.
Novelist he may have been, but I have to say that his proposal to the Board of Longitude manages to be both cryptic and tediously long-winded – in part, I think, in his attempt to intrigue the Board without giving his secrets away. What he wants, he says, is to show his device in person. The one bit I did rather like was his point that dead reckoning is essential around the British coast, ‘considering, the nature of our climate; as in fact, cloudy weather, accompanied by dense fogs, may almost be deemed, one of the prognostics attending, an approach, to the British Channel, during the winter season’. It’s the sort of weather in which observations to determine local time from the sun (which you need to do even with a chronometer) would be impossible, and so an additional way of determining one’s position would be essential.
Sadly, the Board was not impressed enough to take Higginson’s ideas further and (coincidentally) was wound up the same year.
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