( 1 ) THESE writ petitions are taken up together for hearing as the question involved in all these writ petitions is in respect of issue of a writ of Mandamus restraining the respondents from levying and collecting the tax under the Andhra pradesh, Nonagricultural Land Assessment Act (Act XIV of 1963)

( 2 ) IN these writ petitions the legislative competence to make amendment to S. 2 (d) of the said Act and also the definition of the term industry (Industrial purpose ?) under this section are challenged. To have a clear idea of the several points raised, we will narrate the facts of writ petition 3494 of 1978.

( 3 ) THE petitioners-Associated cement companies Limited Mancherial, are the owners of 338 acres 22 guntas of and on which the cement plant for the manufacture of cement is erected. It is stated that only on 32 acres 18 guntas the machinery is set up where the manufacturing process takes place and in the said are the company has constructed certain buildings where the staff of the company work in connection with the manufacture. The company has also constructed certain houses to accommodate its staff and workers and the area covering these residential quarters