The Signal insulators were the workhorses of the telegraph line. Dits and dahs of railroad business, news and even personal telegrams streamed along copper wire attached to this sage green beauty.
Some collectors like insulators with what we call "Junk in Glass". At the top of the skirt just below the wire groove two small pieces of fire brick from the furnace are forever suspended inside the glass. This is a fairly common occurrence in older insulators that adds a bit of charm and character.