Observations on a pamphlet, entitled, A short history of opposition, during the last session of Parliament : with a postscript to the author, containing, some seasonable strictures on his arguments in support of a corrupt influence in the Crown, and its necessary operations upon a factious and servile majority of the other two branches of the legislature : to which is prefixed, an address to Messrs. Wedderburne, Gibbon, and M'Pherson /