Most likely built and operated by one of the many, many Ma-and-Pa phone companies that were springing up all over the United States in small communities like this after the the invention of the telephone.

A lot of these very early endeavors were built by using whatever was laying around, surplus-bought and non-standard odd-ball equipment, etc., which certainly must have graced such early openwire lines doing their job with *all* sorts of insulators that one can only dream of...