Only at four by-elections in twentieth-century British history has there been a turnover of more than 18,000 votes: at Dudley in 1968, at Orpington in 1962, at East Fulham in 1933 and at Dartford in 1920. Dartford and Orpington have been commented upon as landmarks in the histories of the Labour and Liberal Parties respectively, and Dudley is likely to be seen as the outstanding manifestation of discontent with the economic policies of the Labour Government in the 1960s. East Fulham, however, is the most notorious of all the “boilover’ by-elections. Taking place in a decade troubled by depression and fear of war, it resulted in a National Government majority of 14,521 votes being transformed into a Labour Party majority of 4,840, on a massive swing of 26–5 per cent.