The City Manager shall appoint the City Secretary with the approval of the City Commission and such assistant City Secretaries as the City Commission shall deem advisable. The City Secretary, or an Assistant City Secretary, shall give notice of Commission meetings, shall keep the minutes of the proceedings of such meetings, shall authenticate them by the Secretary's signature and record in full in a book kept and indexed for the purpose, all ordinances and resolutions, and shall perform such other duties as the City Manager shall assign to the City Secretary and those elsewhere provided for in this Charter. Moreover, until such time as the City Commission shall designate a "City Treasurer", the City Secretary shall also function in such capacity.