The Clerk of said City shall be, ex officio, Clerk of the City Council and, as such, shall have the custody of all books, papers, and records of said City, keep a record of the proceedings of the Board, certify copies thereof, and, except as otherwise provided, shall perform the usual duties of a town clerk. The other officers elected at the annual meetings of said City shall have the same powers and duties and be subject to the same restrictions and liabilities as are now provided by law for the various town officers. All officers of the City shall be sworn for the faithful performance of their duties.