( 1 ) THESE two sales-tax revision petitions are presented under S. 23 (1) of the Karnataka Sales Tax Act, 1957 (hereinafter referred to as the 'act') by a registered dealer against the orders of the Karnataka Appellate tribunal confirming the orders of the appellate and Assessing authorities. The only question of law that arises for consideration in these two revision petitions is as follows: -"whether the notification issued under Sec. 8a of the Act exempting the purchase turn-over of old gold and silver articles from the levy of sales tax under S. 6 of the Act became invalid with effect from 1-7-1972 with effect from which date sub-sec. (1) of Sec. 5 was amended enhancing the rate of tax payable on general goods from 3 to 31/2% ?"

( 2 ) THE petitioner is engaged in purchasing old gold and silver articles and manufacturing gold and silver jewellery out of it and selling them, for the assessment years 1973-74 and 1974-75 the petitioner furnished his returns. During the relevant years he had purchased old gold and silver articles from individuals who were not liable to pay sales Tax under the, Act. Thereafter the assessee prepared gold and silver jewellery out of the g