As my Meridian journey comes to an end (at least for the time being) it was only fitting to visit the place where it all began. The Greenwich Observatory.
We set off, on a blistering hot day in the middle of July, for two days in Greenwich, to meet the heroes of my story really – the Harrison Clocks.
John Harrison, lived in Barrow – about 30 miles north of my home – he performed his first sea trials of the now famous H1 clock, on the Humber Estuary, before continuing with his other clocks H2, to H5.
Harrison was born in Yorkshire – moving with his family to Barrow when only a youngster – he and his brother together built a number of long case clocks (the first of which is now in a museum in Leeds) – a further clock, commissioned for the turret of the stables at Brocklesby park was made of oak, and Lignum Vitae (a very oily wood that made lubrication of the clock unnecessary). Here it is, and still running for the last 300 years.
Harrison was a man of many skills and he used these to systematically improve the performance of the pendulum clock. He invented the gridiron pendulum, consisting of alternating brass and iron rods assembled so that the thermal expansions and contractions essentially cancel each other out. Another example of his inventive genius was the grasshopper escapement– a control device for the step-by-step release of a clock’s driving power. Developed from the anchor escapement it was almost frictionless requiring no lubrication because the pallets were made from wood. This was an important advantage at a time when lubricants and their degradation were little understood.
In his earlier work on sea clocks, Harrison was continually assisted, both financially and in many other ways, by George Graham the watchmaker and instrument maker. Harrison was introduced to Graham by the Astronomer Royal, Edmund Haley. who championed Harrison and his work. This support was important to Harrison, as he was supposed to have found it difficult to communicate his ideas in a coherent manner.
(London viewed from the Greenwich Observatory)
And the observatory itself.
You can see from the crowd how busy the place actually was. It was impossible to get a straight shot of the Meridian Line.
Also, sadly, my site here does not support video, so I am unable to upload the video I did of the H1 – H3 clock movements. However, you can see below – the changes from H1 to H4 (I didn’t see H5, as this is in a different location in London).
Harrison died on March 24, 1776 at the age of eighty-two, just shy of his eighty-third birthday. He was buried in the graveyard of St John’s Church Hampstead, in north London, along with his second wife Elizabeth and later their son William. His tomb was restored in 1879 by the Worshipful Company of Clockmakers, even though Harrison had never been a member of the Company.
Harrison’s last home was 12, Red Lion Square in theHolborn district of London. There is a plaque dedicated to Harrison on the wall of Summit House, a 1925 modernist office block, on the south side of the square. A memorial tablet to Harrison was unveiled in Westminster Abbey on 24 March 2006, finally recognising him as a worthy companion to his friend George Graham and Thomas Tompion, ‘The Father of English Watchmaking’, who are both buried in the Abbey. The memorial shows a meridian line (line of constant longitude) in two metals to highlight Harrison’s most widespread invention, the bimetallic strip thermometer. The strip is engraved with its own longitude of 0 degrees, 7 minutes and 35 seconds West.
A further memorial to John Harrison will be erected in Barton town centre later this year. I believe the installation of the statue will be in September, with a formal unveiling in October of 2019.
I hope you have enjoyed this meridian journey with me. Maybe there will be more to come.
In the meantime, I hope to have this talk ready for the road by the end of September this year. I look forward to hearing from you.