‘Compared with that of Banks, Mr. Green’s [Endeavour] equipment was comparatively modest’. H.C. Cameron, Sir Joseph Banks, Angus and Robertson, Sydney, 1966
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‘John Harrison, the man who solved longitude in 1759’. Peter Ackroyd, Revolution, Macmillan, London, 2016
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‘With his marine clocks, John Harrison tested the waters of space-time….He wrested the world’s whereabouts from the stars, and locked the secret in a pocket-watch [H-4]‘. Dava Sobel, Longitude, Fourth Estate, London, 1998
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Greenwich Observatory: Who was Mr. Green? Charles Green had been Assistant Astronomer to Rev. James Bradley and Rev. Nathaniel Bliss, Astronomer Royals at Britain’s Greenwich Observatory.
In 1764 Green, owing to Bliss’ ill-health travelled to Barbados with astronomer Nevil Maskelyne. Their task to compare Maskelyne’s method of determining longitude based on his Nautical Almanac with that of H-4 aboard HMS Tarter on a supervised timed-voyage England to Barbados.
Green returned to Greenwich convinced of H-4’s reliability to tell ‘true-time’. Time was the essential ingredient needed to calculate ‘longitude’ when a ship at sea was out of sight of land.
Tahiti :Yet, as designated astronomer on the Endeavour voyage 1768-1771 to Tahiti and beyond he was denied John Harrison’s chronometer. See The Third Man – Charles Green
‘H-4 [was] bolted to a window seat in the Observatory’. Dava Sobel, Longitude, Fourth Estate, London, 1998
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1675: To advance the science of astronomy n 1675 The Restoration King Charles II, commissioned Sir Christopher Wren to build an Observatory. The Reverend John Flamsteed was appointed England’s first Astronomer Royal. His annual salary of £100 was ridiculously low.
Wren found an ideal site in Greenwich Castle. Although its buildings had been substantially damaged by Oliver Cromwell’s New Model Army during England’s Civil Wars in the first half of the century the foundations were intact.
Once a favourite haunt of King Henry VIII who used it as a hunting’ lodge it was no longer suitable for a king. Flamsteed laid the Observatory’s foundation stone in August 1675.
1676 -Greenwich Observatory: The build was swift. In July the following year when Flamsteed took up residence he found there was very little equipment to work with.
Off-the-shelf as well as bespoke instruments had to be purchased and there was a chronic shortage of money to buy them .Despite this and, migraine headaches a life-long affliction, Flamsteed’s long tenure, he died in 1719, was very productive.
He produced a Star Catalogue that ‘contained the position of over 3000 stars calculated to an accuracy of ten seconds of arc’.
Plagiarism – the actions of two (2) scientific luminaries,related to the Star Catalogue, marred his time at Greenwich.
Flamsteed’s deteriorating relations with Edmond Halley, when combined with the malicious influence of Isaac Newton, led them to print and publish his work without permission.
1720: On his death in 1720 King George I – German George – appointed Edmond Halley, of comet fame, England’s second Astronomer Royal.
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Dava Sobel says Halley’s imagination had been fired much earlier on observing;‘a more common transit of Mercury from St Helena…in 1677’.
In 1716 he had postulated there would be two (2) transits of Venus in the decade 1760. Furthermore Halley predicted another century would pass before such a phenomenon would be seen again.
It was this last that stirred the Royal Society into action.
‘On May 5th, 1768, at a meeting of Council of the Royal Society it was resolved that the [Banks] instruments for the use of the Observers of the South Latitudes be the following:
Two [2] reflecting telescopes of two [2] foot focus…[1] brass Hadley’s sextant, [1] barometer bespoke of Mr Ramsden, [1] Journeyman’s Clock bespoke by Mr Skelton, two [2] Thermometers of Mr Bird, [1] Stand for Bird’s Quadrant, [1] dipping needle bespoke by Mr Ramsden’. Cameron. op. cit.
Tahiti: After the Admiralty rejected Alexander Dalrymple, a member of the influential Scots ‘Dalrymple Dynasty’, first choice of the Royal Society, that august body engaged Charles Green to represent them at Tahiti there to observe and record the Transit of Venus. See: The Third Man
Edmond Halley of comet fame had predicted the planet Venus would pass across the face of the sun on 3 June 1769. The Admiralty supplied a ship HMS Endeavour, its captain Lieutenant James Cook RN and a Royal Navy crew.
‘John Harrison, the man who solved longitude in 1759’. Peter Ackroyd, Revolution, Macmillan, London, 2016
Plymouth: So why in August 1768, ten (10)years after the longitude problem had been solved, was Harrison’s marine ‘pocket-watch’ chronometer ‘H-4 bolted to a window seat in the [Greenwich] Observatory’ and not aboard HMS Endeavour when she sailed from Plymouth. See: Captain Cook, John Harrison, Charles Green – Three Yorkshire Men Walked Into A Bar
No doubt H-4 sat under the watchful eye of Rev. Nevil Maskelyne Britain’s fifth Astronomer Royal who had been appointed to that high post in 1765 on the death of Rev. Nathaniel Bliss. Maskelyne held a conservative stranglehold over the position until 1811.
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