sentences:  In 1820 the British authorities persuaded about 5,000 middle-class British immigrants (most of them "in trade") to leave England behind and settle on tracts of land between the feuding groups with the idea of providing a buffer zone.The plan was singularly unsuccessful.Within three years, almost half of these 1820 Settlers had retreated to the towns, notably Grahamstown and Port Elizabeth, to pursue the jobs they had held in Britain.