Download Transcript: Text

In the last episode we talked about how the naturalist Alfred Russel Wallace had accepted a wager from the flat-earther John Hampden, offering 500 pounds to anyone who could prove that earth is round. They had gone to the Fens and made observations of the view along a canal, and where we left off, they had returned to London without managing to reach an agreement on what the observations had shown, and hence who had won the wager.

The participants hadn't even agreed on what the experimental design was supposed to be. The globe earth contingent claiming that they were supposed to be looking from one bridge to a marker on another bridge at the same height, and observing whether a third marker, half way between the bridges, at the same height again, appeared above the line of sight as you would expect on a globe, and the flat-earthers claimed that they were supposed to be looking horizontally as determined by the telescope's crosshairs, and observing the alignment of the markers relative to a line of sight parallel to the surface of Earth.

If you remember from the last episode, the terms of the wager were that each of the participants should appoint a referee, and the two referees would decide who had won the wager. Wallace had appointed Henry Walsh, the editor of the hunting and fishing magazine The Field, while Hampden had appointed the notorious flat-earther William Carpenter. Walsh had had to return to London before their business in the Fens was finished, so he had been replaced with the local surgeon and amateur astronomer Martin Coulcher.

Coulcher and Carpenter had failed to reach an agreement, and according to the terms of the wager this meant they had to appoint a third umpire to decide between them.

A few days later, back in London, they actually managed to agree to appoint Henry Walsh to this role. Of course, he agreed with Wallace and Coulcher.

The whole escapade was written up in Walsh's magazine The Field, making a jarring appearance amid articles about shooting and horses and tweed jackets, with the diagrams of the views through the telescopes and everything. They include reports from the two referees, Coulcher and Carpenter, and diagrams of both observations - that is, both Wallace's original plan, with the telescope aimed at the bridge six miles away, and Carpenter and Hampden's impromptu modification, with the telescope positioned level and the elevations of the bridge and the marker compared to its crosshairs.

Needless to say, in both cases the result is consistent with a curved Earth, with the middle post appearing above the line of sight in the first, and both the bridge and the middle marker appearing below the telescope crosshair in the second, although Carpenter is obviously still insisting that the first experiment was invalid, and that the second experiment proved his case. As an aside, I still haven't been able to understand Hampden and Carpenter's geometrical reasoning, with arguments like:

Modern Flat-Earth arguments about perspective could be related. The idea that things further away look lower down, which is why sunsets look like the Sun is being obscured by the horizon while remaining at a similar distance when in actual fact the Sun is disappearing because it moves further away. We won't talk about the contradictory claim that 'the horizon always rises to eye level', which flat-earthers will absolutely not shut up about as a proof that Earth is flat.

Walsh regretted his earlier judgement of Hampden and Carpenter's honesty, pointing out that Hampden claimed this experiment had never been conducted before, while in Rowbotham's pamphlet Zetetic Astronomy, which if you remember Hampden had bought the copyright for, Parallax describes doing similar experiments, on exactly the same stretch of water, allegedly showing the opposite results.

“The good faith and perfect fairness of Mr Carpenter were not, therefore, quite of the nature we then believed them to be, and we have no hesitation in affirming that he was a most improper person to be selected to act as referee in such a matter.”

A week later, in the next issue of the Field, it became clear that this controversy wasn't going away. Hampden, Carpenter and Wallace all wrote in with their own opinions on the affair. Carpenter's letter, responding to Walsh's comments the previous week, begins:

“Sir. With reference to your idea of my opinion of the article of the fifth instance, I beg leave to say that, if the words “thank you for your article” express extreme pleasure, not only with the article as a whole, but with certain sentences, then did I, in writing, express myself as being, with those generalities and particulars, 'extremely well-pleased', as you say in your last issue. But, as I am never pleased with errors, though I may not at once set about correcting them, I must suggest that you consider the words 'thank you' as having been used in a colloquial sense, and not for one moment as being either eulogistic or confirmatory”.

Next there's a letter from someone called Thomas Westlake, attempting to argue that if the points were equidistant then that would in fact prove Hampden's point but that they weren't actually equidistant. Hampden, of course, triumphantly mocks him in his pamphlet Water Not Convex (which is also the source of much of this story as told here), claiming that the points were equidistant and as such, by the word of a globe-earther, he ought to have won the wager.

“The points, then, were equidistant; and, as Mr Westlake says - and it requires but very little common sense to see this - a line that will take in the three points is a straight line. By this telescope, then, Mr Wallace, not only is your case not proved, but that of Mr Hampden is! Can you escape from this?”

Westlake was wrong here (and indeed he also wrote in to the next issue of the field admitting he was wrong, although this time round seems to have been confused by the fact that they were looking through an inverting telescope, showing an upside-down image). On a flat earth you would expect the points all to be at the same level, and on a globe you would expect them to middle one to be lower than the cross hair, and the further one to be lower than the middle one, with the middle one slightly closer to the cross hair than to the lower one. If they were perfectly evenly-spaced then that would be consistent with a diagonally sloping earth, which I don't think anyone is suggesting.

To Westlake's credit, I haven't seen any actual measurements showing the points to be exactly equidistant. All Hampden is doing seems to be just subjectively judging by eye that they look like they're at about the sam distance, and even that's based on sketches done by Carpenter and Coulcher of what they can see through the telescope. It's quite likely that if you actually measured them, and accounted for atmospheric refraction bending the light rays coming from the markers slightly reducing the apparent effect of Earth's curvature, you would find that they actually weren't perfectly equidistant, and that the difference between the two distances would turn out to match what you'd expect on a globe.

In Water Not Convex Hampden proceeds to keep bringing up the same points about the experimental method, rehash the arguments about whether aiming the telescope at the further bridge is correct, accuse The Field of falsifying the sketches in the editions they printed (the copies printed in the cover of Hampden's book look about the same to me), and criticises another account of the experiment by Samuel Rowbotham of all people (who obviously thought it did indeed prove earth was flat) for reprinting Coulcher's diagram.

He ends with a fiery exhortation addressed to Wallace in person:

“Mr Wallace! By the fact that the five views are now more fully known, and their agreement questioned, by the fact that, in the end, you will have to rely upon the truth, by the fact that the eyes of the world are upon you, and the fact that your fair reputation as a man of science may, possibly, be sullied by your own negligence, we counsel you to yield, quickly and cheerfully, to the force of circumstances; and, even if it be no more than by the ticking of the death-watch at Downham Market, to say nothing at all about the consciousness which you must carry with you concerning your duty to God and man, to the Truth and Mr John Hampden, we counsel you to refund, at all events, the sum of five hundred pounds which was awarded to you by Mr Walsh, and which you received on the first of April, 1870, and, with all gracefulness, admit that water is not convex, and the Earth, not a globe!”

Samuel Rowbotham himself, the originator of the flat earth movement, obviously brought his own opinion to bear on the issue, with the pamphlet Experimental Proofs That The Surface Of Standing Water Is Not Convex But Horizontal. He was surprisingly critical of Hampden and Carpenter, and pissed off that he, the main flat earth guy, wasn't told about it, saying

“I wrote enquiring as to the nature of the experiments to be made and the place and time and persons concerned in the matter, but could get no information. I was kept in entire ignorance of the whole affair until it was over. I could not but feel that this was altogether injudicious on the part of Mr. Hampden and his referee, Mr Carpenter, and very unfair both to myself and to the public. Common justice ought to have suggested to Them that no such attempt to settle so important a matter should have been made without an invitation to the author to be present. More especially should this have been done when it is known that both Mr. Hampden and Mr. Carpenter were literary, and not scientific gentlemen. They knew little or nothing of the nature of the instruments employed in the experiments, and became literally the helpless victims of their more philosophical and practical opponents.”

Obviously Rowbotham's scientific experience trying to make people immortal and designing strange railway carriages would have put him in a much better position next to Wallace's background as a surveyor and civil engineer (and also one of the most important naturalists in history but that's less important here).

As well as the objection that they shouldn't have done it without him, he criticises Hampden and Carpenter for letting Wallace involve himself at all in actually making the observations, saying first off, actually quite sensibly, that they should all have stood back and got some unconnected surveyors to conduct the observations and report their results. His next criticism is that instead of designing their own experiments, they should have repeated the ones that he conducted (obviously the only experiments worth bothering with) in the same place back in 1838 at the Manea Fen Colony. For instance, he goes on to describe the experiment where he watched a boat with a flag on sail away along the canal and the flag 'remained visible the entire distance'.

He goes on to, predictably, say:

“Had Messieurs. Hampden and Wallace conferred with, or invited me to take part in their operations, I could have shown and satisfied them that what they proposed to do and the instruments they were about to employ, as well as their mode of application, were in every sense unsuitable for the object they had in view, and could not lead to definite and satisfactory results.”

His next point is that the experimenters had agreed to use a disk on the further bridge instead of a rectangular marker and to have a marker close to the telescope, neither of which were done. I'm not sure what either of those things would have changed, but Parallax insists that if those conditions had been met then the experiment would have proved Earth was flat. The next point is a bit more interesting, and he says that the drop measured in the second experiment was much less than the globe model would predict. Parallax says that this means the curvature cannot be the cause of the drop, and instead says that the most likely cause is errors in the setup of the spirit level and the telescope.

This might be a fair criticism (Hampden and Carpenter did indeed seem to have no idea what they were doing), but the difference from the predicted drop could also be accounted for by atmospheric refraction - that is, differences in the density and water vapour content of the air causing the light rays coming from the markers to bend, making them appear significantly higher up than they actually are. I don't know which is correct, maybe they both are, but the first experiment, much better designed, by Alfred Russel Wallace, which didn't depend on the calibration of equipment but just on looking in a straight line to something that you had measured to be the same height, demonstrated pretty much exactly the curvature Wallace predicted.

Rowbotham actually goes on to attribute the apparent drop (and indeed the apparent drop of the horizon in all situations) to atmospheric refraction. The error here is that atmospheric refraction wouldn't be a particularly significant effect on a flat Earth. The differences in the density and composition of the air are mostly in layers parallel to the surface of the Earth, so on a globe light rays between objects at the same height pass through multiple layers of air and are refracted, while on a flat earth they wouldn't encounter significant changes, so would be completely horizontal. Add to that the fact that air lower down is usually denser than air higher up, which means atmospheric refraction usually makes objects look higher up than they actually are.

Next up, Rowbotham reveals that he himself made a trip back to the Bedford Level and made his own measurements. At the Old Bedford Bridge, he got the captain of a boat carrying turf along the canal to take him as far as Welney. All the way, he looked through the telescope, 18 inches above the water, and the Old Bedford Bridge remained visible, where by his calculations it should have been hidden behind the curve of the Earth on the globe model.

Of course, as in all his Bedford Level experiments, he made no attempt to account for atmospheric refraction, which is really quite a big effect when you're looking from that close to the surface of a body of water, and would make the bridge visible for much further than you would otherwise expect. Wallace's experiment (at least, after they had got rid of all the extra poles), was very well-designed in this regard. They were looking from much higher above the surface of the water, so the effect of refraction was much less, and in any case refraction would affect the lines of sight to both markers (although it would admittedly affect the further marker more).

The science journal Nature picked up on the article in The Field, saying:

“A RECENT number of the Field contains an account of a very amusing investigation which has been recently conducted on the Bedford Level to settle the question whether the earth is a globe or not!”

And then a multitude of local papers ran pretty much verbatim-identical little articles on the experiment, citing Nature.

And what follows next is suggested by the fact that it is discussed in a chapter of Wallace's autobiography titled “A CHAPTER ON MONEY MATTERS—EARNINGS AND LOSSES —SPECULATIONS AND LAW-SUITS”.

Hampden wrote to Walsh to demand his stake back, because, after all, the decision was unjust and he had been right the whole time. Hampden began sending hate mail to Walsh, and then to Wallace, to Wallace's Wife, to Wallace's Cook, even to the Astronomer Royal George Airy, who we met earlier, saying

“If your lying impostures last much longer, you may rest assured that the ultimate exposure which inevitably awaits you will cause you great discomfort.”

His sent this one to Annie Wallace, Alfred's wife:

"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.”

Hampden ended up spending a week in prison for this one, and bound over to keep the peace for three months, and then was straight back at it. In January 1871, Wallace sued for libel, and won, but Hampden had transferred all his property to his son-in-law, so Wallace got nothing. In July of that year, he got a letter from Charles Darwin himself about the whole situation:

“I was grieved to see in the Daily News that the madman about the flat earth has been threatening your life. What an odious trouble this must have been to you.”

Over the next few years, Hampden was forced to publicly apologise (printed in various newspapers) to Wallace. He was sentenced to two months in prison at one point, and later to a year (although he only served 6 months).

Of course the hate mail kept coming the whole time, including this one to the publishers of a new edition of the Encyclopaedia Britannica featuring articles by Wallace:

“I have felt it my duty to suggest to the publishers of the new edition of the encyclopaedia that the admission of articles from convicted thieves and swindlers cannot possibly do them or their work any credit”.

And this surprisingly sensible suggestion:

“If you are not conscious that your conduct has been that of a swindler throughout, why don't you have the view along the six miles of the Bedford Level photographed!”

Then, in 1876, he sued Henry Walsh for the money from the wager. It looks like British law at the time basically didn't recognise wagers as a thing, so Hampden technically was entitled to the £500 (about 60,000 modern pounds), and got the money back. Wallace in fact ended up having to pay several hundred Victorian pounds (or tens of thousands of modern pounds) because he had agreed to cover Walsh's legal costs, although he doesn't say exactly how much, so he's really come off quite badly out of this whole affair.

Of course, Hampden was back at it yet again, culminating in 1885 with an extraordinary letter to the President of the Royal Society, Thomas “Darwin's Bulldog” Huxley, with a postscript aimed squarely at Wallace, opening:

“I have thoroughly exposed that degraded blackleg, Alfred Russel Wallace, as I would every one who publicly identifies himself with such grossly false science, which he had the audacity to claim to be true! If this man's experiment on the Bedford canal was founded on fact, then the whole of the Scriptures are false, from the first verse to the last.”

Alfred Russel Wallace's autobiography quotes sections such as:

“When Mr. Mundella and Mr. Gladstone were schoolboys, the educational professors were all newly indoctrinated with the pretentious learning of the 'Principia' of Newton. The Bible was not regarded as of any authority upon such subjects, and a flood of writers were all extolling the immortal genius of the 'incomparable mathematician.' Newton and his apple-tree were spoken of as the foundation of all true philosophy. The plausibly sounding phrases 'Attraction' and 'Gravitation' were in every pedagogue's mouth, and the poor children were birched into repeating them every hour of their lives.”

(with Mr Gladstone being Liberal Party leader William Ewart Gladstone, at the time the leader of the opposition (who would become Prime Minister the following year), and Mr Mundella being the Liberal MP Anthony Mundella, who was well known as a supporter of universal education, and as so closely associated with the idea of a centralised educational establishment. And indeed the previous two Liberal governments, both under Gladstone, had passed the Education Acts of 1870 and 1880, the latter nicknamed Mundella's Education Act, which had established a system of universal primary education in England and Wales)

And then there was a leaflet that he sent to basically everyone whose address he could find who had anything to do with Wallace, Including a lot of the population of his home town of Godalming in Surrey. I will quote Wallace, in turn quoting the leaflet (because I couldn't find the leaflet except what Wallace quotes):

“It was full of—"scientific villainy and roguery,"—"cheat, swindler, and impostor."—"My specific charge against Mr. A. R. Wallace is that he obtained possession of a cheque for £1,000 by fraud and falsehood of a party who had no authority to dispose of it."—"As Mr. Wallace seems wholly devoid of any sense of honour of his own, I shall most readily submit the whole matter to any two or more disinterested parties, and adhere most absolutely and finally to their decision."— "I will compel him to acknowledge that the curvature of water which he and his dupes pretend was proved on the Bedford Level, does not exist! And this Mr. Wallace saw with his own eyes." And so on in various forms of repetition and abuse.”

Wallace responded with his own pamphlet (which he doesn't quote), and then just ignored him…

Until Hampden actually showed up it his house.

Wallace got rid of him, but says in his autobiography

“I afterwards much regretted that I did not ask him in, give him luncheon, and introduce him as the man who devoted his life to converting the world into the belief that the earth was flat. We should at least have had some amusement; and to let him say what he had to say to a lot of intelligent people might have done him good.”

Hampden kept going at least until December 1885, when the last of his publications that Wallace mentions maintains that “no one but a degraded swindler has dared to make a fraudulent attempt to support the globular theory”, and goes on to offer another wager, £100 for “the discovery of any portion of the Earth's curvature, on land or water, railway or canal, of not less than five or ten miles, within one hundred miles of the metropolis.”

It wasn't really worth it in the end for Wallace. He says how this whole affair cost him much more than the £500 he ended up winning, as well as having to receive death threats.

Samuel Rowbotham had died in 1884, maintaining the flatness of the Earth until the end. Carpenter emigrated to America, publishing A Hundred Proofs Earth is Not a Globe in 1885, which begins with the straightforward argument that “the aeronaut can see for himself that the Earth is a plane”, and ends with an utterly incomprehensible argument about the International Date Line. It's still one of the most popular flat earth texts. He died in Baltimore in 1896. There's less written about Hampden (he doesn't even have his own Wikipedia page) after the Wallace affair, but he appears to have died in 1891.

Wallace remained an intriguing and complicated figure, and deserves a greater exploration in his own right, with his adventures in the Malay Archipelago, his co-discovery of natural selection, his dabbling in the occult, his anti-vaccination activism, and his opposition to the scientific racism that was fashionable at the time to some extent a reminder that what is now scientific orthodoxy was not necessarily always so, and that people can end up firmly on the right side of history in some cases and on the wrong side in others.

The flat earth movement was picked up by another generation, with the Universal Zetetic Society founded by the Seventh-day Adventist John Williams in Southwark in 1892, and bankrolled by the eccentric aristocrat Lady Elizabeth Blount, who returned to the Bedford Level in 1904 to conduct another experiment, having a photographer beside Welney Bridge take a photograph of a screen beside the Old Bedford Bridge, six miles away, that should have been hidden by the curvature of the Earth if the Earth were a globe and you ignore refraction (which would in fact have been an even greater effect than usual, given the misty weather conditions).

In America, the New York Zetetic society, founded in 1873, had fizzled out a bit by the time Carpenter arrived, but his Hundred Proofs went some way to revitalising the American flat earth movement, and he ended up promoting the Universal Zetetic Society's magazine Earth Review in America, although his enthusiasm for Spiritualism led to fallings out with the Seventh-day adventists who formed a large part of the American flat earth movement.

Future notable proponents of flat earthism included Wilbur Glen Voliva and his Christian Catholic Apostolic Church at Zion, Illinois, a utopian community (or cult) that he ran from 1906 until his death in 1942, and the Dover signwriter Samuel Shenton, who founded the International Flat Earth Research Society in 1956 and pioneered the flat earth response to the emergence of space exploration.

In the end, like many fringe beliefs the internet brought about a bit of a revival. Like the growth of mass literacy and increased availability of printed material in the industrial revolution, another step in the democratisation of knowledge is accompanied by a flourishing of strange ideas espoused by people who can seem superficially convincing to a large proportion of the population.

What we also see in this story is a question of whether it's a good idea for serious intellectuals to engage with cranks at all. Wallace got a lot of shit for this, with the point being made that he was making flat earth beliefs seem like they were comparably respectable to mainstream cosmology, and just that, as Joseph Hooker wrote to Darwin, “it was not honourable, to a scientific man, who was certain of his ground.” And in hindsight, Wallace regretted the whole thing and to me, who has spent far too much time looking through flat earth arguments online, it seems like it should have been obvious that Hampden and Carpenter were never going to engage in good faith with the wager and accept the results. But if this kind of movement was relatively new at the time, maybe we can forgive Wallace for not realising this, and accept that we've learned the same lesson from this that Wallace learned, that there are beliefs that it's not worth trying to debunk.

On the other hand, even if Hampden and Carpenter weren't convinced, there might have been other people reading the reports on it, the sort of people who would have been writing to George Airy with questions about Parallax's lectures, who might otherwise have found flat-earthism persuasive, but watched Hampden and Carpenter make idiots of themselves as Wallace quite straightforwardly demonstrated the curvature of the earth. Lyell suggested as much when he told Wallace to go ahead with it, and I think Wallace probably had more respect than many of his peers for the way in which the flat-earthers at least purported to go about finding knowledge, he himself having started out as a self-taught outsider to the scientific establishment, and I think it's likely he expected Hampden and Carpenter to be more intellectually honest and earnestly curious than they turned out to be.