In granting permits to erect poles for purposes of electric light or power the city reserves the right, if the interests of the city so demand, to authorize other companies to use the same poles for the same purposes upon the payment to the owners thereof of a proper compensation which shall be determined between the parties concerned or by the city council in default of such agreement. All permits will be subject to this condition, and in accepting a permit the applicant accordingly binds himself thereto. (Code 1941, Art. 105-31)