134. If the office of the Chairman of the Commission becomes vacant or if the Chairman is by reason of absence or for any other reason unable to perform the duties of his office, those duties shall be until some person appointed under sub-section (1) of section 129 to the vacant office has entered on the duties thereof or, as the case may be until the Chairman has resumed his duties, be performed by such one of the other members of the Commission as the Sadar-i-Riyasat may appoint for the purpose.