It is unlawful for any person, firm or corporation to attach or maintain any telegraph, telephone or electric light, electric or power wire to any pole in the streets of the city at a distance of less than twenty two feet (22') from the ground at all points where the wires overhang any part of the street, provided trolley wires shall not be less than twenty feet (20') from the street grade. It is unlawful for any person, firm or corporation to attach electric light and power wires on the same cross arm with telegraph, telephone or other signal wires; and when placed on the same pole with such wires the distance between the two (2) inside pins of each cross arm shall be not less than twenty four inches (24") for circuits operating at a potential to ground not exceeding three hundred (300) volts and shall not be less than thirty inches (30") for higher potential; provided, that cross arm carrying such other wires must be at least thirty six inches (36") from cross arms previously attached. (Prior code § 8-4-9)