Excise duty exemption for processed cotton and cellulosic spun yarn: no additional excise required where earlier duty was paid. The Central Government directs that where cotton yarn or cellulosic spun yarn falling under the specified tariff headings was subjected to processes such as beaming, warping, wrapping, winding or reeling and duty on the base yarn had already been paid, the excise duty that would otherwise be payable shall not be required to be paid in respect of those clearances which were not charged under the prevailing non-levy practice.