It shall be lawful to
construct and maintain a railway, with all necessary, proper and usual works
and conveniences in connection therewith, along the line described in the
Schedule to this Act, but that portion of the railway authorised to be
constructed between Mundijong and Jarrahdale by this Act shall not be so
constructed unless and until the parties to the agreement have, pursuant to
clause 28 thereof, agreed on the terms and conditions upon which that portion
is to be so constructed.