An old woman of Naples immortalised by her invention of a tasteless and colourless poison, called by her the Manna of St. Nicola of Bari, but better known as Aqua Tofana. Above 600 persons fell victims to this insidious drug. Tofana died 1730.
Hieronyma Spara, generally called La Spara, a reputed witch, about a century previously, sold a similar elixir. The secret was revealed by the father confessors, after many years of concealment and a frightful number of deaths.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894