Originally Posted by John_Conrad
not sure why they advertise...are there any other free ways to post photos?
Photobucket wants you to pay them for ability to link to photos hosted by them.
The stone has just been rounded off that way, maybe on purpose to grind a groove in something maybe not. Maybe just someone grinding on the edges too much. It's an old electric motor name and an arbor. Have seen that motor name on different kinds of old machine tools.