" The notification dated 28.2.1982 under which the credit is claimed reads: "In exercise of the power conferred by sub rule (1) of rule 8 of the Central Excise Rules, 1944, and in supersession of the Noti fication of the Government of India in the Ministry of Finance (Department of Revenue) No. 178/77 Central Excise, Dated 18 June, 1977, the Central Government hereby exempts all excisable goods (hereinafter referred as "the said goods") on which the duty of excise is leviable and in the manufacture of which any goods failing under 327 Item No. 68 of the First Schedule to the (1 of 1944) (hereinafter referred as "the inputs") have been used as raw material or component parts (hereinafter referred to as "the inputs") from so much of the duty of excise leviable thereon as is equivalent to the duty of excise already paid on the " 'inputs".