K.S.Tiwana, J.

1. The petitioner, M/s. Troks Pharmaceuticals Private Ltd., Bahadurgarh (for short the company), has filed these two Civil Writ Petitions No. 4500 of 1981, Troks Pharmaceuticals Private Ltd., Bahadurgarh v. Excise and Taxation Officer, Bahadurgarh, and Others and No. 1986 of 1982, Troks Pharmaceuticals Private Ltd., Bahadurgarh v. Excise and Taxation Officer, Bahadurgarh, and Others. As a matter of fact, the same question of law is involved in both these petitions. The facts are exactly similar. The respondents are common. The annexures are also common. For these reasons, both these petitions shall be decided by one judgment recorded in C. W. P. 1986 of 1982.

2. The company is engaged in the business of manufacturing and selling drugs/ medicines, etc. The petitioner-company made sales to various Health Departments of different State Governments which they had ordered for the supply to various hospitals established under the Employees State Insurance Scheme. The sales to the State Governments are chargeable at four per cent of taxation under Section 8(1) of the Central Sales Tax Act, 1956 (Act No. 74 of 1956) (briefly the Act). Prior to the amendment effected