Section 127. Franchises and privileges

Without first having obtained the
  permission and approval of the  commissioner  no  common  carrier  shall
  begin  the  construction  of  a  railroad  or  street  railroad,  or any
  extension thereof, for which a certificate  of  public  convenience  and
  necessity  shall  not  have  been  granted  by  the  board  of  railroad
  commissioners or where prior to said time said common carrier shall  not
  have  become entitled by virtue of its compliance with the provisions of
  the railroad law to  begin  such  construction;  nor,  except  as  above
  provided  in  this  section,  shall any such common carrier exercise any
  franchise or right under any provision of the railroad law,  or  of  any
  other  law,  not  heretofore  lawfully  exercised,  without first having
  obtained  the  permission  and  approval  of   the   commissioner.   The
  commissioner  shall  have  power  to  grant  the permission and approval
  herein specified whenever he shall after due hearing determine that such
  construction or such exercise of the franchise or privilege is necessary
  or convenient for the public service.