So, an “eternity box” is a coffin, to “hop the twig” is to run away & “balderdash” is adulterated wine. Enliven your vocabulary with this & much more 18th century slang, as recorded in Grose‘s Classical Dictionary of the Vulgar Tongue (1788):
Grose‘s Classical Dictionary of the Vulgar Tongue
Mark Beré Peterson: Hauntings, Urban Legends, History, Folklore, Mythology and Witchcraft 