Exemption power for foreign travel tax: government may exempt classes or individuals subject to conditions and recorded reasons. Section 46 authorises the Central Government to exempt classes of passengers by Gazette notification or individual passengers by written order from foreign travel tax, wholly or in part, subject to specified conditions and limitations; class exemptions require satisfaction that they are necessary in the public interest, while individual exemptions require recorded reasons demonstrating necessity or expediency given the passenger's special circumstances and purpose of travel.