law: 9. Police-officers not to resign without leave or two months' notice.
  No police-officershall be at liberty to withdraw himself from the duties of his office unless expressly allowed to do so by the District Superintendent or by some other officer authorised to grant such permission or, without the leave of the District Superintendent, to resign his office unless he shall have given to his superior officer notice in writing, for a period of not less than two months, of his intention to resign.