Tariff amendment: petroleum crude newly classified with nil excise duty while other petroleum oils remain charged under substituted items. Amendment to the Fourth Schedule substitutes heading 2709 in Chapter 27 with tariff item 2709 00 and subitems 2709 00 10 (Petroleum crude) and 2709 00 90 (Other), specifying the unit as kilograms and providing duty treatment, including a nil excise duty entry for petroleum crude under 2709 00 10.