The petitioner, a dealer in yarn at Guntur, placed orders for yarn from the Gokak Mills in Mysore State. When the consignments of yarn were in transit, he sold them to various purchasers by endorsing the railway receipts. The turnover in respect of these transactions came to Rs. 12,97,097. The petitioner claimed exemption from central sales tax under section 6(2) of the Central Sales Tax Act. The sales tax authorities did not allow the exemption on the ground that the petitioner did not file the declaration in form C as prescribed by rule 12(3)(ii) of the Central Sales Tax (Andhra Pradesh) Rules, though he filed form E-1. In this application for the issue of a writ, the petitioner claims that under section 6(2) of the Act, filing of form E-1 was enough to entitle the petitioner to claim the exemption and rule 12(3)(ii) which stipulates the filing of form C also is ultra vires as it is inconsistent with section 6(2) of the Act. Sri P. Rama Rao, learned counsel for the petitioner, relies on the decision of the Madras High Court in State of Madras v. Subbiah Pillai ([1967] 20 S.T.C. 263.), and of the Gujarat High Court in State of Gujarat v. Yakubbhai Hajihakumutdin ([1969] 23 S