ISMAIL, C.J.

All these cases involve the same point and are therefore disposed of by a common judgment. The petitioner in T.C. Nos. 894 and 895 of 1977 is one and the same and these tax revision cases are concerned with assessment under the Tamil Nadu General Sales Tax Act and the Central Sales Tax Act for the year 1973-74. The tax revision cases have been preferred against the order of the Board of Revenue (Commercial Taxes), Madras, dated 26th February, 1977, suo motu revising the order of the Appellate Assistant Commissioner, Kancheepuram. T.C. No. 591 of 1979 has been preferred by the State against the order of the Tamil Nadu Sales Tax Appellate Tribunal (Main Bench) dated 14th December, 1978, in respect of the assessment for the year 1976-77 dealing with another assessee. W.P. Nos. 4951 and 4952 of 1978 have been filed by the same assessee praying for the issue of a writ of prohibition. The two writ petitions have been filed, one in respect of the assessment under the Tamil Nadu General Sales Tax Act and the other with reference to the assessment under the Central Sales Tax Act. The prayer in the writ petitions is for the issue of a writ of prohibition restraining t