He shall keep the books and accounts of the board, record or file their proceedings and papers, attest all orders and warrants issued by them, and perform all other duties pertaining to his office as clerk; he shall before entering upon the duties of his office take and subscribe the oath prescribed by section one of article seven of the Constitution of this Commonwealth, which oath or affirmation shall be filed by such clerk in the office of the clerk of the court of quarter sessions of the same county.