For the most part they were old locomotive wheels. The fire company I'm a member of had one in the early 1900's, it was replaced with an electric siren.
In Ringwood, the next town up from me, the Stonetown Fire Company has a loco wheel hung in front of their firehouse.
Joe P
Joe P, KC2PJL
Charter Member of the Red Knights International Motorcycle Club, NJ Chapter 15
Amateur radio....the only REAL radio left in the world.
Emergency Services Dispatcher