( 1 ) SINCE common questions were involved in a number of writ petitions, we proceeded to hear arguments in these cases and sought assistance from all Counsel appearing in various matters.

( 2 ) ARGUMENTS of both the parties were heard at some length. In these cases, challenge has been laid to the validity and vires of Section 3a of Central Excise Act, 1944 apart from Notification Nos. 24/97,30 to34/97,57/97and58/97and all other connected notifications. In addition, the petitioners have also made a grievance of the scheme whereby modvat credit standing to the credit of various petitioners to the with drawal of modvat credit w. e. f. 1. 8. 1997. Notonly that, by that very scheme/ decision, respondent No. 1 has deprived the petitioners of the modvat credit already accrued and available to them. The lapse of the modvat credit in the account of assessees is in the nature of giving retrospective effect to the said notification whereby the credit already earned is sought to be taken away. In the original Act prior to enactment of Section 3a, the charging section imposed liability to excise duty on the goods manufactured which was in consonance with Entry No. 84 in List I of Se