Tangling with a Flat-Earther

Today is the centenary of the death of the great biologist and collector Alfred Russel Wallace, co-originator with Darwin of the theory of evolution by natural selection. Wallace's star has been rising lately, thanks in part to the promotional efforts of scientist-comedian (they're becoming increasingly indistinguishable) Bill Bailey, who was again talking about Wallace on Radio 4 this morning. I thought there might even be a Google doodle, but no...
  In his time, Wallace, despite his brilliance, fell foul of many of his fellow scientists for taking a lively interest in spiritualism and survival after death. He was also strongly opposed to vaccination. However, on the question of the curvature of the Earth, he was entirely orthodox - so, when one John Hampden offered £500 to anyone who could prove convex curvature in a body of water, the always cash-strapped Wallace took up the wager.
  Hampden was a supporter of Samuel Rowbotham, founder of Zetetic Astronomy, a system that proposed a flat, disc-shaped Earth, centred on the North Pole and bounded by ice. Rowbotham's observational experiments on water had satisfied him and his followers that the Earth is indeed flat. But, as Wallace realised, Rowbotham and others had not allowed for refraction when making their observations. By setting up the sight line 13ft above the water, Wallace was able to demonstrate clearly that there is indeed a perceptible curvature in a large body of water, and he was declared winner of the wager.
 Unfortunately, this was not good enough for the pugnacious Hampden, who accused Wallace of cheating, refused to accept the result, and pursued him relentlessly through the courts, until he was himself imprisoned for libel and threatening to kill Wallace. Unfortunately, the court also ruled that Wallace must return the wager money as the bet was not valid.
 Here is one of Hampden's letters to Wallace's wife:

Mrs. Wallace,
Madam — If your infernal thief of a husband is brought home some day on a hurdle, with every bone in his head smashed to pulp, you will know the reason. Do you tell him from me he is a lying infernal thief, and as sure as his name is Wallace he never dies in his bed.
You must be a miserable wretch to be obliged to live with a convicted felon. Do not think or let him think I have done with him.
John Hampden

 Charming. Flat Earth Theory lives on, of course, and there is still a Flat Earth Society, based in Lancaster, California. One thinks of Masters of Atlantis and the Gnomon Society of America...