The latter most likely was for a fire alarm telegraph circuit. Typically (at least through the teens) such lines were strung above all other circuits so that no other wires could fall upon them since they were highly vital for instant fire reporting.

A 12-pin crossarm for local telephone subscribers is immediately beneath. Lower on the same pole are two electric wires that reached out to a small incandescent street light mounted over the middle of this Iowa town's business district.