9(1)If a person to whom a pension has been granted under paragraph 4 or 7 above is appointed to an office in any public department the pension shall not be paid for any period after that appointment if his annual salary in that office (" the new salary") is equal to his last annual salary in the office from which he retired when the pension was granted (" the salary before retirement").
(2)If the new salary is less than the salary before retirement the amount of the pension shall not exceed the difference.
(3)In sub-paragraph (1) above the reference to an office in a public department includes a reference to employment in any body or institution listed in Schedule 1 to the [1972 c. 11.] Superannuation Act 1972, or to an office so listed.