RAMACHANDRA IYER, J.

These appeals, which are filed under Clause 15 of the Letters Patent against the judgment of Rajagopala Ayyangar, J., in W.P. Nos. 1287, 1288 and 1469 of 1956, raise a common question relating to the constitutional validity of the revised rules 15 and 16 of the Turnover and Assessment Rules made by the Government of Madras under sections 3, 5 and 19 of the Madras General Sales Tax Act, 1939, and published in the Fort St. George Gazette on 7th September, 1955. The appellants in the various appeals are tanners and dealers in hides and skins, tanned and untanned. The respondent in the respective appeals issued notices to them, calling upon them to submit returns and pay tax in advance in accordance with rule 5 of the Madras General Sales Tax Rules and the revised rules 15 and 16 of the Turnover and Assessment Rules. The appellants, therefore, moved this court by means of the petitions aforesaid for the issue of a writ under Article 226 of the Constitution to direct the respondent to forbear from enforcing the rules, after declaring them illegal. The case for the appellants is that rules 15 and 16 of the Turnover and Assessment Rules, which were publishe