From Mr Neil Robertson.

Sir, With reference to Brian Groom’s potted history of the postal monopoly (Notebook, November 3): he would perhaps have benefited from reading Ronald Coase’s Historical Survey of 1955 commemorating the old Dundee School of Economics and Commerce, supplemented by a trip to Dundee’s Howff, where a gravestone “To the memory of James Chalmers” notes that this Dundee bookseller and Convenor of The Nine Incorporated Trades of Dundee was (his son says) the “originator of the adhesive postage stamp which saved the penny postage scheme of 1840 from collapse rendering it an unqualified success and which has since been adopted throughout the postal systems of the world”.