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Bedford Level experiment
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The Bedford Level experiment was a series of attempts, beginning in the late 19th century, to deny the curvature of the Earth's surface. First conducted by Flat-Earther Samuel Birley Rowbotham, observations along a long straight stretch of drainage canal in the English county of Norfolk seemed to confirm that the Earth is flat.
The basic idea was to use a surveyor's telescope to observe marks at a uniform height above the water, spaced three miles apart.[1] If the earth is curved, the marks will not line up. Mariners had been correcting their lunar sights for the atmospheric refraction of light near the horizon since the eighteenth century, but the flat-earth proponents failed to account for it, and claimed the observed existing misalignment showed curvature (on still water) but much less than the crazy Round-Earth fanatics had predicted.
Years later, Rowbotham's results were taken up by one of his supporters, one John Hampden, who wagered a bet that he would prove the earth is flat. Alfred Russel Wallace took him up on this, and by accounting for optic refraction, he repeated the experiment and showed the Earth to be curved. Wallace was judged the winner by the editor of The Field (a gamblers' magazine), but Hampden claimed Wallace had cheated. Death threats, libel cases,[2] and Hampden's incarceration ensued.
Samuel Rowbotham's Experiment (1838)[edit]
The Crank[edit]
Samuel Birley Rowbotham, the father of modern flat earth crankery, was an elementary-school dropout, snakeoil salesman with no medical degree,[3] and who got several people killed with his phosphorus based cure-all "medicine". He also accidentally poisoned one of his children, who then died. At the age of 46, he married a 15 year old girl with whom he produced 15 children.
The Crank Experiment[edit]
The experiment took place at the Old Bedford River (map, street view), that is 6 miles (9.66km) long and roughly 10 m (30ft) wide.
Rowbotham estimated the drop over 6 mile distance to be 8 inches per mile. This is acceptable, as the approximation formula produces only 0.6mm of error at three mile mark.
The curve was observed at 8 inches (20.3cm) altitude. The target was a boat that had a flag on it, the tip of which was at 3 feet (91 cm) height from the water. Rowbotham claimed the boat was visible entire time, and that in the globe model, the mast should have been 11 feet (3.4m) below his line of sight.
Alfred Russel Wallace's Reproduction (1870)[edit]
In 1870, Alfred Russel Wallace, a naturalist, explorer, geographer, anthropologist, biologist, an illustrator, and a qualified surveyor,
took one John Hampden's 500 pound wager (63,500 USD, inflation adjusted to Dec '24), to replicate Rowbotham's Bedford Level experiment.
Wallace removed errors from Rowbotham's experiment. He didn't go hang about in the canal, or use flimsy boats. He strived for replicability of his experiment.
The observation point (Point A) was the Old Welney Bridge (52°31'10"N 0°15'03"E). Wallace wanted to minimize the effect of refraction, so from the observation point, he set a sight line at the altitude of Welney bridge's railing. The distance from the top of the iron parapet of the bridge, to the surface of the water below it, was 13ft 3in = 403.86cm.
The sight line's target (Point C) would be at the Old Bedford Bridge (52°27'05"N 0°09'46"E) that was 6.00 miles (9.66 km) North-West from the Welney bridge's observation point. Because Welney bridge was made of bricks, Wallace had to mark the sight line. This was done by attaching a 6 feet wide by 3 feet tall white cotton cloth, with a large black horizontal line, to the side of the Old Bedford Bridge. The height of the cloth was set so, that the bottom of the black line also sat 13 feet 3 inches (403.86 cm) above water.
A marked stick (Point B) was then placed in the exact middle point between the two bridges, i.e., 3 miles from both bridges. The stick had two large red discs. The middle point of the upper disc was also set at altitude of 13 feet 3 inches (403.86 cm). The second disc was 4 ft (121.92 cm) lower, i.e., its middle point was 9 feet 3 inches (281.94cm) above water.
The prediction Wallace made was this: If the Earth was flat, (Fig. 2), then, when observing the sight line with a telescope, the upper disc will be at the same altitude as the sight line. If on the other hand, Earth was round, (Fig. 1), then the middle point of water would bulge, and upper disc would be 5 ft 8 in (172.72 cm) higher, and since the lower disc was only 4 feet below the upper one, even that one would be above the sight line. Wallace estimated atmospheric refraction to cause roughly 8 inches (20 cm) inches of deviation.
The result that both Wallace and Hampden observed and signed, showed obvious curve:
This debunked Rowbotham's hand-wavy experiments that failed to account for atmospheric refraction and proved the curve.
The bitching and whining[edit]
According to wikipedia, Hampden who lost the bet, refused to accept the result. He wrote pamphlets that called Wallace a cheater, and like a good charlatan, sued Wallace to get his money back. He was also imprisoned for libel and for threatening to kill Wallace.
Today, flerfs like Eric Dubay lie by omission by telling the story of all Rowbotham's experiments, but they do not even mention Wallace's experiment that revealed flerfs' party trick.
Further reading[edit]
- Rob Hernlund - Flat Earth Confusion: Rowbotham Missed the Boat (2023) ASIN: B0BTKHP3MW
See also[edit]
External links[edit]
- See the Wikipedia article on Bedford Level experiment.
References[edit]
- ↑ Scientific American, Rosetta Stones: "Wallace’s Woeful Wager: How a Founder of Modern Biology Got Suckered by Flat-Earthers"
- ↑ The Form of the Earth— A Shock of Opinions New York Times, August, 1871
- ↑ which makes it even funnier when Eric Dubay calls Rowbotham a doctor.