law: 4. Making, variation and revocation of schemes. -
  (1) The Government may, by notification in the Official Gazette and subject to the condition of previous publication, make one or more schemes for a port or group of ports, and may in the like manner and subject to the like condition add to, amend, vary or revoke any scheme made by it.
  (2) The provisions of section 23 of the General Clauses Act, 1897 (10 of 1897), shall apply to the exercise of a power given by sub-section (1) as they apply to the exercise of a power given by a Central Act to make rules subject to the condition of previous publication.
  (3) The Government may direct the port authority of any port to prepare, in accordance with such instructions as may from time to time be given to it, one or more draft schemes for the port, and the port authority shall comply with such direction.