Pierre Denys de Montfort was a French naturalist who had a thing for giant octopuses. According to him, there were two types: the kraken of Norse mythology, and the much larger colossal octopus, whose hobbies included attacking ships and taking up lots of space.

And so, when a group of British warships vanished into thin air one night in 1782, de Montfort jumped to the obvious conclusion and told everyone they’d been sunk by giant octopuses. Turns out, the navy knew exactly what had gone down, and it wasn’t octopuses, giant or otherwise. de Montfort was thoroughly discredited and his career tanked. He did leave us with some pretty imaginative illustrations, though.