At the climatology blog Watt’s Up With That, guest blogger Tim Ball has a story of how an obscure fort in remote Churchill, Manitoba on the west coast of Hudson’s Bay became the avenue for a scientific competition between France and the British Empire that shaped the world by validating Newton’s Law of Gravitation — or would have done, if the damnable instruments worked. A key player was a British scientist of unprepossessing background:
He obviously showed mathematical ability because in 1765 he entered the employ of the Astronomer Royal, Sir Nevil Maskelyne. He began work on one of the two major scientific challenges of the day, the accurate determination of longitude. However, that was to become interlinked with the other challenge, testing of Newton’s Theory of Gravitation, published in 1687.
There were several possible ways to do this, and the way that Sir Nevil proposed, Wales didn’t think would work. He got assigned to do it any way — he would go to Churchill, and on the other side of the world, explorer Captain James Cook would be in Tahiti, and they would observe the transit of Venus across the Sun, timing it with precision chronographs, and then by application of trigonometry, they’d have the missing ingredient to plug into Newton’s law of gravity.
Previous attempts by both European rivals had failed; the next window was 1769.
The major reason for the 1761 failure, inadequate instrumentation, was not resolved. Nobody knew this better than William Wales. In a parallel of today’s global warming fiasco, the scientists, who were effectively bureaucrats or relied on sponsorship, believed that political support and more money was the answer. So Wales faced a dilemma, keep your mouth shut and do what the King and his lackeys like Maskelyne wanted, or face incarceration and possibly even hanging.
Wales didn’t think the instruments were accurate enough.
Finally, Wales agreed to take up the challenge, but only after negotiating a generous contract that included provision for his family should he not return….
Wales knew the accurate timing was essential to success. He also knew the problems of producing an accurate chronometer. One was specially constructed, and on the Atlantic crossing, he tested it rigorously only to discover it was losing several minutes every day. It was inadequate.
They took a prefabricated observatory with them and on arrival set it up on the SE bastion of Fort Prince of Wales.
In the Georgian era, Wales couldn’t just send for a new chronograph from the remote wilderness of Churchill. And he couldn’t use the one the Royal Observatory had given him. He was trying to measure an angle that would turn out to be 9.57 milliradians. So what options were left?
He built a sundial. (Image at right). Archaeologists unearthed it at the Fort and it now rests in the Parks Canada museum in Churchill.
The challenge for Wales was to establish some way of determining time more accurately than with his failed chronometer. During the restoration of the Fort, a remarkable sundial was dug up at the base of the wall. They also found an iron spindle that allowed the user to turn any of 24 faces toward the Sun.
Ball and Leslie Ross were able to demonstrate that the sundial definitely was Wales’s: it contains the same exact error that is in his after-action report to Sir Nevil and the Royal Society.
In a 1984 article “Observations of the Transit of Venus at Prince of Wales’s Fort in 1769” I identified the latitude Wales had calculated for the Fort. Leslie Ross, a researcher at the National Museum of Canada, was also doing research on the sundial. He asked where I obtained the latitude. I told him it was the one Wales recorded in his journals. He said the latitude matched his calculations for the latitude of the major sundial face (June 1983 Stone sundial from Fort Prince of Wales. Research Bulletin #193). It was clear evidence that Wales made the sundial because both latitudes were different from the actual latitude by 11 minutes. I was skeptical that a sundial could be better than even a faulty chronometer, but Ross told me it could determine the time to within two minutes, which made it superior to the watch.
And the report itself says something about Wales:
On his return to England Wales … refused to submit his report. He said the results were of no value. The timing was imprecise, and the telescope optics were inadequate. Wales was finally ordered to submit a report that was published in the Philosophical Transactions of the Royal Society.
We are fortunate he complied because Wales did not waste his time but carried out countless other experiments and made many observations. He brought the first barometers and thermometers, constructed to Royal Society specifications to northern North America. He produced an excellent instrumental record beginning in 1768. This continued after he left because he instructed the surgeon in their use.
In the end, Wales’s imperfect measurement of the transit of Venus was overtaken by better measurements, validating Newton’s law. And he resumed work on his other great challenge, measuring longitude.
Far from being angry with Wales, his peers were impressed with his integrity, and when he resumed work on the longitude problem…
Two years after his return to England, the Board of Longitude commissioned him to sail as astronomer and navigator with Captain Cook. Wales job, in association with William Bayly, was to test Kendall’s K1 chronometer based on the H4 of John Harrison.
These superior chronometers resolved many problems, and Wales is a fine representative of the many nameless scientists who toiled (and still toil) in the shadows, gradually dragging the world of the past into a better informed future. Do Read The Whole Thing™.
And what of Fort Prince of Wales? This may have been its high point. While it had 42 guns and another battery of six more across the Churchill River, its garrison was depleted and construction ceased after 1771. During a French raid in 1782, the garrison comprised only 39 civilians, and the fort was surrendered to the French with no resistance or loss of life, and its structures and goods sacked and burned. The cannons on its walls? They never fired a shot in anger. It’s now a Canadian national park and tourist attraction… for tourists willing to travel to someplace that is still quite remote.