PITTSBURGH (KDKA) -- Unless you're an architect or an engineer, it's probably been years since you last used a protractor in geometry class.
But, now the semi-circular tool is showing up in some odd places around town, from mailboxes to utility equipment.
Protractors have been pasted in public places from the North Side to the East End by way of Garfield where John Perry catches his bus by the mailbox.
"It might be a marker for certain cans they're supposed to pick up and empty or the ones they're going to remove and renew. I don't know," he guessed.
That just doesn't add up.
It appears a private protractor placer throwing us a curve within a three-mile radius.
Each one is numbered.
Polish Hill proves to be a protractor placer's paradise. Residents Jim Mueller and Ilona Auth have their own opinions.
"It could either be a renegade math freak or someone who just loves intrigue," Mueller said.
"Maybe they're trying to measure the angle of the hills," Auth said.
It's a matter of degree. Mark Knobil checks out number 142 next to Lili's Coffee Shop.
"It's clearly a protractor," he said. "Three dimensional. It's stuck on there really well. It's not going anywhere. Maybe it's just telling us we have no idea what the heck is going on."
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