( 1 ) THE petitioner-firm, since the year 1965, had been manufacturing "ultramarine blue" at its factory at 59, Grand Trunk Road, Liluah, District Howrah. The petitioner-firm had taken out requisite licence for manufacturing excisable goods and had also executed necessary bond under the Central Excise Rules, inter alia, undertaking to produce for charge of duty all excisable goods manufactured in its factory, to maintain accounts and to pay excise duty leviable thereon, etc. Both the petitioner and the Central excise authorities, until the time mentioned hereinafter, had acted on the basis that ultramarine blue manufactured by the petitioner was included within Item No. 141 (5) of the First Schedule to the Central Excises and Salt Act, 1944. The petitioner was being assessed under Section 3 of the Central Excises and Salt Act, 1944, in respect of ultramarine blue according to the rate of duty mentioned against the goods specified in Item No. 141 (5) of the First Schedule to the said Act.

( 2 ) ON 20th August, 1971, a learned Judge of the City Civil Court, Ahmedabad, had decreed a civil suit brought by M/s. C. M. C. India, inter alia, for declaring that th