1. - This writ petition has been filed by an Ex Employee of the Rajasthan High Court who has superannuated on 14.11.69 on completion of the age of fifty five years. At the time of superannuation, he was holding the post of Asstt. Registrar and his pay on that date was Rs. 575/- basic plus Rs. 120/- D.A., total Rs. 695/- In view of the terms of Rule 256 of the Rajasthan Service Rules, 1951 which govern the Computation of the pension, the petitioner was granted pension by computing the average emoluments of years preceding the date of retirement and by excluding the D.A. According to Rule 256 at the relevant time, the pension was 30/80 of average emoluments with the maximum of Rs. 8100/-. on 18.2.71, Rule 256-A was inserted in the Rules by a notification issued by the State Govt. which came into force from 1.4.70. By the notification, the computation of the pension was liberalised and it was ordered that the computation of pension will be on the basis of the last drawn emoluments instead-of three years average emoluments. This change in the rules was made effective from 1.4.70. Consequently, the benefit of the revised pension was denied to the pensioners who had retired befo