( 1 ) THE common question raised in all these writ petitions relates to the validity of rule 39-A added to the Mysore Sales Tax Rules in November 1962.

( 2 ) THE petitioners in all these cases deal in hides and skins. These are declared goods within the meaning of the Central Sales Tax Act and are liable to single point levy of tax under the Mysore sales Tax Act, in accordance with the provisions of sub-section (4) of section 5 of the said State act.

( 3 ) BECAUSE the goods are declared goods, as of importance from the point of view of inter-State trade, tax thereon payable under the Central Act as well as several State Acts is controlled by the provisions of section 15 of the Central Sales Tax Act. That section reads as follows :-

"15. Restrictions and conditions in regard to tax on sale or purchase of declared goods within a state.- Every sales tax law of a State shall, in so far as it imposes or authorises the imposition of, a tax on the sale or purchase of declared goods, be subject to the following restrictions and conditions, namely :- (a) the tax payable under that law in respect of any sale or purchase of such goods inside the state shall not exceed two