From www.mysteriousbritain.co.uk
"In her book Somerset Folklore Ruth L Tongue records a local tradition recorded in 1890, of how a researcher in the 18th century was told by a farmer that he had heard the sound of someone shouting “come over and fight” one foggy night in the vicinity of the battlefield. This was said to have been the battle cry of the Duke’s men, desperately shouting at James’s army to join them in battle as they were mown down by musket balls. Although the farmer believed that the source of the voice must have been a drunkard, the tale has now become the tradition that the battle site is haunted by the sound of ghostly cries. "