The petitioner is a firm, inter alia, carrying on business of import and sale of different edible oils and other allied products. On 1-7-1977 a public notice was issued by the Collector of Customs, to the following effect-

"G.S.R. 463(E).-In Exercise of the powers conferred by sub-sec. (1) of Section (25) of the Customs Act, 1962 (52 of 1962) and in supersession of the Notification of the Government of India in the Department of Revenue and Banking (Revenue Wing) No. 25-Customs, dated 8th February, 1977, the Central Government, being satisfied that it is necessary in the public interest so to do, hereby exempts palmoleins falling within Chapter 15 of the First Schedule to the Customs Tariff Act, 1975 (51 of 1975) when imported into India from the whole of the duty of customs leviable thereon which is specified in the said First Schedule."

2.Thereafter, on 11th January, 1978, the petitioner's orders were confirmed by the brokers. On 18th February, 1979, there was a shipment of a stated quantity, which need not concern us. The ship actually arrived on 22nd February, 1979. On 1st March, 1979 the following notification came to be issued :

Government of India

Ministry of Financ