and since in the absence of the two years ' notice required under the old s.7(4), the option of purchase on the expiry of December 2, 1960 could not be legally 192 exercised, the new s.6(1) did not confer any option of purchase on the expiry of December 2, 1960 and the first option exercisable under the new s.6(1) would be on the expiry of December 2, 1970; (3) sub sections (4) and (5) of the new s.6 show that the period on the expiry of which the option under sub s(1)of s.6 is exercisable, is a period which would expire at least 18 months after the coming into force of the new s.6, that is to say, after September 5, 1959, and since the period expiring on December 2, 1960 is not such a period, the new s.6(1) did not confer any option of purchase on the expiry of December 2, 1960; and (4) in any event, the State Electricity Board having duly elected to purchase the undertaking on the expiry of December 2, 1960, the State Government acquired no option of purchase under sub s(2) of s.7 of the .