The Science of Discworld IV Judgement Da - By Terry Pratchett, Ian Stewart Page 0,45
long stretch of the Old Bedford River in Norfolk, remodelled as a straight canal. If the theory that the Earth is round has any merit, it ought to be possible to observe the curvature by sighting along the surface of the river. In 1838 Samuel Birley Rowbotham did just that, wading into the river with a telescope and watching a boat as it rowed the six miles to Welney bridge. He reported that the boat’s mast, five feet tall, remained in view the entire time: clear evidence for a flat Earth.
Rowbotham led a colourful life. He was an organiser of an Owenite commune in the Norfolk Fens, which practised the socialist utopian views of the reformer Robert Owen. After allegations of sexual peccadillos, Rowbotham travelled the country giving lectures about why the Earth is flat and science had got it wrong. At a lecture in Blackburn, a member of the audience asked why ships disappear from the hull up when they sail out to sea, until only the tops of the mast remains visible. Unable to answer, Rowbotham fled the lecture hall, but he learned from the debacle, improved his debating skills and found plausible counters to the usual arguments for a round Earth. He published his views in 1849 in a pamphlet called Zetetic Astronomy. Later he put them in a second pamphlet, The Inconsistency of Modern Astronomy and Its Opposition to the Scripture, whose title hints at a possible motive.
Public scepticism ran high, and he was repeatedly asked to carry out proper experiments, but he always refused. By 1864, however, the pressure had become so intense that he set up an experiment on Plymouth Hoe, an open area of ground where Sir Francis Drake memorably played bowls in 1588 while waiting for the tide to turn so that he could attack the Spanish Armada.fn3 If the Earth were round, then only the top of the Eddystone lighthouse, 14 miles away, would be visible through a telescope; if it were flat, the entire lighthouse would be visible. The result was decisive: only half of the lantern was visible. Rowbotham resorted to a standard pseudoscientific response to contrary evidence: ignore it and claim the opposite. Under the name ‘Dr Samuel Birley’ he allegedly sold cures for all human diseases and claimed the ability to prevent ageing. His patents include one for a life-preserving cylindrical railway carriage. In 1861 he married his laundress’s sixteen-year old daughter, and they had fourteen children.
In 1870 John Hampden wagered that he could show, by repeating Rowbotham’s Bedford Level experiment, that the Earth is flat. He encountered a formidable opponent: Alfred Russel Wallace, who had trained as a surveyor. We met Wallace in The Science of Discworld III: Darwin’s Watch. On 1 July 1858 his paper ‘On the perpetuation of varieties and species by natural means of selection’ was read to the Linnaean Society, along with a very similar work ‘On the tendency of species to form varieties’ by Charles Darwin. In his annual report the President of the Society, Thomas Bell, wrote: ‘The year which has passed has not, indeed, been marked by any of those striking discoveries which at once revolutionize, so to speak, the department of science on which they bear.’ The two papers had announced the theory of evolution by means of natural selection.
At any rate, Wallace accepted Hampden’s wager. His surveyor’s training allowed him to avoid the errors of the preceding experiments and he won the bet. Hampden published a pamphlet alleging that Wallace had cheated, and sued for his money. Several lengthy court cases ensued, and eventually Hampden was jailed for libel.
Rowbotham was not to be silenced. In 1883 he set up the Zetetic Society, a forerunner of the Flat Earth Society, with himself as president. It had branches in England and the United States. One of his supporters, William Carpenter, published Theoretical Astronomy Examined and Exposed – Proving the Earth not a Globe using the pseudonym Common Sense. He followed it with A Hundred Proofs the Earth is Not a Globe. One was the observation that many rivers flow for long distances without descending more than a few feet, an example being the Nile, which drops one foot in a thousand miles. ‘A level expanse of this extent is quite incompatible with the idea of the Earth’s convexity. It is, therefore, a reasonable proof that Earth is not a globe.’
It pays to check the facts. The Nile is fed from Lake Victoria, although there are other rivers that run