The judgment of the Court was delivered by

B. P. JEEVAN REDDY, J. - Andhra Pradesh Electricity Duty Act, 1939 - originally enacted as Madras Act 5 of 1939 and subsequently made applicable to the entire State of Andhra Pradesh - provides for levy of duty on certain sales and consumption of electrical energy by licensees in the State of Andhra Pradesh. Section 2 defines certain expressions occurring in the Act. "Energy" is defined to mean electrical energy [clause (a)]. "Licensee" is defined to mean :

"(i) any person including a company or a local authority licensed under Part II of the Indian Electricity Act, 1910, to supply energy, or any person including a company or a local authority who has obtained the sanction of the State Government under section 28 of that Act to supply energy;

(ii) the Andhra Pradesh State Electricity Board constituted under section 5 of the Electricity (Supply) Act, 1948;

(iii) the National Thermal Power Corporation or any other corporation engaged in the business of supplying energy" [clause (b)].

Section 3 is the charging section. Sub-section (1) alone is relevant for our purposes, and may be set out in full :

"3. Levy of duty in certain sales o