From the
article:
"As a champion of science and evolutionary thinking, [Alfred Wallace] 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. "
"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."
Adjusting 500 pounds for inflation via
measuringworth.com:
In 2009, £500 from 1870 is worth:
£35,500.00 using the retail price index
£294,000.00 using average earnings
Converting pounds to dollars via google:
35500 British pounds sterling = 57222.4500 US dollars
294000 British pounds sterling = 473898.6000 US dollars
As we can see, Wallace had a very strong incentive for rigging or lying about this experiment. Considering the wager involved amounts like this it's no wonder Hampden sent Wallace death threats in response to his cheating.