Correspondents include: Sir Horace Hamilton [Permanent Secretary, Board of Trade] (10); Alfred Hurst [Principal Assistant Secretary, Treasury]; Cyril Hurcomb [Permanent Secretary, Ministry of Transport] (3); James Grigg [Principal Private Secretary to the Chancellor of the Exchequer] (4); Edward Hale [Treasury] (2); Sir Francis Floud [Chairman, Board of Customs and Excise] (4); Edward Shrapnell-Smith, President, Commercial Motor Users' Association; Sir John Cadman (2); Sir Robert Waley-Cohen (2); Robert Shackle [Assistant Principal, Board of Trade]; Sir Robert Robertson, Government Chemist; Harry Ricardo.Also includes: copy of the 4th report of the Application Committee; tables on revenue and finance for the scheme; copy letters and minutes from WSC to some of those mentioned above and to Sir John Anderson [later 1st Lord Waverley, Permanent Under-Secretary of State, Home Office] and Prime Minister Stanley Baldwin.Subjects include: the level of tax for different types of oil; revising motor vehicle taxation; additional duty on motor spirit; variations on the scheme; Benzol production; the additional burden on the railways of the tax; the protection of chemical frontiers; the possibility of an increase in the price of petrol; avoidance of the duty; the colouring of non-dutiable oil.