It is a tool used for spreading ink more evenly on a printing press.

"Look Out Schrodinger's Cat! It's A Trap!" 2XL Please.

Carl thought he had assembled all the necessary elements for wingless flight: a pair of skis, an old bed sheet from his mother's linen closet, and a six pack of infamous "El Diablo" extra spicy burritos he had for lunch at the base of the mountain.

Sadly, Carl, the bed-sheet, and his underpants did not survive the experience.

It's a "cavalry spur" used by mounted troops in the eighteenth and nineteenth centuries. The rounded end doesn't injure the horse like the spiked wheel design that was made popular by movies and television.