The Prophet Hen of Leeds →
I am no ovologist, but I cannot imagine it being an easy task to re-insert an egg in to a hen.
The Prophet Hen of Leeds was a doomsday hoax involving the Second Coming of Christ in England in 1806.
A hen began laying eggs on which the phrase “Christ is coming” was found to be written. Eventually it was discovered to be a hoax. The hoaxster had written on the eggs in a corrosive ink to etch the eggs, and reinserted the eggs back into the hen.