4. For the purpose of carrying out any survey directed to be made under the last preceding section, or for any or all of the purposes of this Act, the Government may appoint a Superintendent of Survey, who may exercise all or any of the powers of a Collector under this Act; and may appoint one or more Assistant Superintendents and Deputy Collectors, who shall exercise all the powers of a Collector in respect to such matters under this Act as may be delegated to such Assistant Superintendents or Deputy Collectors respectively by the Collector or Superintendent of Survey, and not otherwise: Provided that, notwithstanding the appointment of a Superintendent of Survey for any tract of country, ¹[it shall be competent to the Board of Land Administration to] direct that the Collector shall perform any duties under the Act within the said tract.