For the purposes of enabling the appropriate Government to determine the extent of land to be acquired, it shall be lawful for any officer, either generally or specially authorised by such Government in this behalf, and for his servants and workmen,—
         (a) to enter upon and survey and take levels of any land in such locality;
         (b) to dig or bore into the sub-soil;
         (c) to do all other acts necessary to ascertain whether the land is adapted for such purpose;
         (d) to set out the boundaries of the land proposed to be taken and the intended line of the work (if any) proposed to be made thereon; and
         (e) to mark such levels, boundaries and line by placing marks and cutting trenches and where otherwise the survey cannot be completed and the levels taken and the boundaries and line marked, to cut down and clear away any part of any standing crop, fence or jungle:
     Provided that no act under clauses (a) to (e) in respect of land shall be conducted in the absence of the owner of the land or in the absence of any person authorised in writing by the owner:
     Provided further that the acts specified under the first proviso may be undertaken in the absence of the owner, if the owner has been afforded a reasonable opportunity to be present during the survey, by giving a notice of at least sixty days prior to such survey:
     Provided also that no person shall enter into any building or upon any enclosed court or garden attached to a dwelling-house (unless with the consent of the occupier thereof) without previously giving such occupier at least seven days notice in writing of his intention to do so.