I snapped this picture of what is most likely a Hemingray signal about a mile from my brother's home near Durand, IL. There are miles of clear and blue ones still soldiering on along the back roads between Beloit, WI and Durand, and between Harvard, IL and Rockton.
There are dozens, if not hundreds, of old signals in service on those rural distribution lines. The newer mud pieces on the hot conductor make me believe that the utility company reinsulated and upped the voltage, but left the insulators on the neutral alone. Looking closely at some of them, I noticed that the tie wires are broken or rusted away, and the neutral conductor is just resting on the bracket. Anybody got a ladder? ;-)