( 1 ) IN this petition under Article 226 of the Constitution the petitioner challenges the validity of an assessment order dated 21-9-1957, made under the U. P. Sales Tax Act, 1943, (hereinafter called the Principal Act), and of a notice of demand which is undated but which it is common ground was issued on 22-9-1957.

( 2 ) THE petitioner is a firm which carries on business in Agra in Cloth, supplies of which it obtains from places both within and outside the Uttar Pradesh. It is a registered dealer under section 8a of the Act The tax purports to be levied I under a Notification No. ST/905x, dated 31-3-1956, and it is the validity of that notification which is the principal question which arises in this case. This notification was held to be invalid by this Court in Adarsh Bhandar v. Sales Tax Officer, aligarh, 1957-8 STC 666: ( (S) AIR 1957 All 475) (A), but it is the case of the respondents that subsequent to the judgment in that case the notification has been validated by the U. P. Sales Tax (Amendment) Act, 1957 (U. P. Act No. XXIV of 1957 ).

( 3 ) IT is necessary to refer shortly to certain statutory provisions. Prior to the coming into force of the U. P. Sa