Alfred Russell Wallace was always up for a challenge.
As a champion of science and evolutionary thinking, he was never afraid of adopting unpopular causes (hence his opposition to vaccination, among other things). He was also, sadly, in frequent financial difficulties and worried about supporting his wife and children. A series of bad investments depleted the money he made from bringing back exotic specimens from Malaysia (he was a scientist, not a financial wizard). With the help of friends (including Charles Darwin), he eventually secured a modest government pension in 1881 and made extra money through his writings. Still, he was always looking for new ways to supplement his income.
Unfortunately, this brings us to John Hampden and his Flat Earth wager...
Throughout the latter half of the 19th century, John Hampden represented the public face of flat earth advocates in England. Although largely forgotten prior to 1800, flat earth societies underwent somewhat of a revival with "zetetic societies" expressing their skepticism about orthodox scientific views of the shape of the Earth. Most flat-earthers tend to be religious fundamentalists who based their beliefs on literal Biblical interpretations although they weren't above trying to use science to justify their thinking. The 1849 book, Earth is Not A Globe, by Samuel Rowbotham argued that sunrise and sunset were actually optical illusions caused by light refraction (he also argued that the sun was 32 miles in diameter). John Hampden was very much in Rowbotham's camp and was often confrontational in making himself heard.
When Hampden advertised his infamous Flat Earth Wager in 1870, the terms were simple enough: he would pay 500 British pounds to anyone who could provide absolute proof of a round Earth. Given the size of the reward (which was a hefty sum in those days), Wallace was tempted enough to discuss the wager with Charles Lyell. After Lyell suggested that "It may stop these foolish people to have it plainly shown them", Wallace accepted the challenge. As an experienced land surveyor, designing an appropriate proof seemed simple enough (but he should have realized the offer was too good to be true). Hampden appointed fellow flat-earther William Carpenter as his referee while Wallace appointed science journalist J.J. Walsh. Both Hampden and Walsh put up 500 pounds in a London bank for safekeeping and Wallace signed an agreement that he would repay Walsh if he lost the bet.
The test itself was scheduled for early March, 1870 at the old Bedford Canal in Norfolk (Hampden picked the site). The methodology Wallace used was flawless: he would set three objects spaced three miles apart along a straight line. Using a telescope, he would verify that the middle object would appear five feet or more above the objects at the two extremes, consistent with what was known about the curvature of the Earth. Prior to the experiment, Wallace submitted a diagram to Hampden, Walsh and Carpenter illustrating the planned experiment and none of them objected. On March 5, Walsh was unable to attend and sent a substitute who agreed to act as referee in his place. On the following day, Carpenter, Wallace, and the new referee, Coulcher, ran the experiment and verified that Wallace's predicted findings were absolutely correct.
Then the obfuscation began. After initially agreeing with Wallace, Carpenter changed his mind and claimed that the telescope used was inadequate since it lacked a proper cross-hair or level. When Wallace corrected the telescope and obtained the exact same result, Carpenter agreed to abide by the findings (Hampden refused to look through the telescope himself). Unfortunately, Carpenter suddenly reversed himself and declared that Hampden was the winner. Baffled by Carpenter's behaviour, Wallace and Coulcher went home in disgust. Although J.J. Walsh later reviewed all of Wallace's findings and declared in writing that Hampden had lost the bet, both Carpenter and Hampden sent in convoluted rebuttals that accused Walsh and Wallace of "a gross perversion of the facts".
When Walsh followed through on the terms of the bet and paid Wallace the money, Hampden began a bizarre campaign of harassment directed against Wallace, Walsh, and everyone else he considered to be involved in the wager. Although Walsh and Wallace considered Hampden to be a harmless lunatic, he was an extremely vindictive one. In the following months, Hampden sent them both letters, pamphlets, and leaflets accusing them both of being swindlers. In one incredible letter that Hampden wrote to Wallace's wife, he wrote that, "If your infernal thief of a husband is brought home some day on a hurdle with every bone in his head smashed to a pulp, you will know the reason. Do tell him from me he is a lying, infernal thief, and sure as his name is Wallace, he never dies in his bed. You must be a miserable wretch to live with a convicted felon. Do not think or let him think that I have done with him."
Naturally, Wallace went to the police and laid charges against Hampden. Despite being sent to prison for a week and ordered by the court not to bother Wallace or his family for three months, Hampden wasn't stopped for long. As soon as the three months were over, the harassment began again. Hampden was careful not to make any further violent threats against Wallace but he continued to send letters and pamphlets to every professional organization in the country. By 1871, Wallace had enough of the harassment and sued for libel. Although Wallace won the libel suit, Hampden simply turned over all his assets to his son-in-law and declared bankruptcy. Not only did this free him from any requirement to pay Wallace for damages but it also forced Wallace to bear all court costs.
Hampden still continued with his increasingly bizarre attacks. While Wallace recognized that his adversary was mentally ill, that didn't provide much comfort considering the harm Hampden's accusations were doing to his public image. Although Wallace was able to win an additional libel suit against Hampden (including forcing him to make a public apology), nothing really changed. With the help of his flat-earth friends, Hampden brought a countersuit against Wallace demanding the return of his 500 pounds. Through a obscure legal technicality, Hampden actually won this case and Wallace was ordered to repay the money. After a lengthy legal battle, Wallace was left even more in debt than ever. By the time the whole sorry matter had ended in 1876, Wallace was left with a permanent stain on his professional reputation. He would say afterward that the entire wager had been one of the biggest mistakes of his life. Flat earth advocates (and, yes, there are still a few of them around) continue to invoke the Wallace-Hampden controversy to lend scientific authority to their arguments.
There does seem to be a certain strange irony in the fact that the same libel laws that Wallace used against John Hampden would also be used more than a century later in the 2008 British Chiropractic Association lawsuit against science writer, Simon Singh. Much like Wallace however, the plaintiffs in that case would find once again that suing for libel can be a dangerous business. While using a courtroom to settle scientific arguments is often counterproductiive, there is can be little choice at times. The Hampden case also shows the risks involved in dealing with True Believers, especially when they think they've been wronged.