1. A question of estoppel, arising from a promise of the State Government to recognise a "salestax holiday", arises for consideration in these Original Petitions filed under Art.226 of the Constitution of India. "

2. Based on the report of a committee appointed to examine methods for strengthening the traditional labour-incentive industries of the State, rehabilitation of sick units and growth of new industrial units, the Kerala Government came out with an order on 11-4-1979, approving a package measure for promoting industrial development. So far as small scale industries were concerned, the package included promise of subsidies, development plots, electricity tariff concession, exemption from minimum guarantee (for supply of electrical energy) and salestax concession. In regard to the last-mentioned concession, the proposal was to exempt small scale industries set up after 1-4-1979 from salestax for a period of five years from the date of production. Mini Industrial units, Women's Industrial units and Smalt Scale units set up by Harijans were to get the exemption for three years. The concession was also to be prospectively extended to existing units of the above three