Every officer, elected or appointed, before entering upon the duties of his office, shall take the oath of office prescribed by Section 2 of Article XVI of the Constitution of the State and shall file the same with the Clerk, together with any bond which he may be required by this charter or by the Council to give. The oath and bond of the Clerk shall be filed with and kept by the Treasurer. In case of failure to comply with the provisions of this section within ten (10) days from the date of his election or appointment, such officer shall be deemed to have declined the office and such office shall thereupon become vacant unless the Council shall, by resolution, extend the time in which such officer may qualify as above set forth.