Exemption for castings and forgings used in sewing machine or chaff cutter manufacture requires intended-use verification by officials. An exemption was added for castings and forgings cleared for manufacture of sewing machines or chaff cutters, granting nil duty where the castings or forgings are used in the producing factory or supplied directly from the factory of manufacture to the manufacturer's factory; entitlement is subject to the Assistant Commissioner of Central Excise being satisfied that the items are intended for use in such manufacture.