Harriett continually found herself putting her work aside - to 'clear' (as though it was coffee).  Novelists who have struck a snag in the working-out of the plot are rather given to handling the problem over in this way to the clarifying action of the sub-conscious.  Unhappily, Harriett's sub-conscious had other coffee to clear and refused quite definitely to deal with the matter of the [plot].  (Dorothy Sayers 1932, p.259)