Newton spent much of his life in the fruitless pursuit of alchemy, but along the way discovered and worked-out much else that was real, practical science. And I was thinking about why it is that we can safely dismiss anyone who claims to have invented a perpetual motion machine, but then I thought: even when we fail to achieve a goal, sometimes we succeed in something else.
Is there any record of new science or engineering being discovered by someone who was otherwise trying to build the impossible, even if they failed at said goal? Maybe they invented a new low-friction ball bearing, or discovered a new phenomenon with energy transfer.
Surely out of all the cranks and all of the gadgets they built, one of them must have had something good that was salvagable. I'm interested in this for historical and rhetorical purposes; I'd love to have a good example of how a crackpot can be redeemed, even if by accident.