 In a letter dated 26 July 1669, the minister Louvois gives the order to Captain de Vauroy, Major of the citadel of Dunkirk, to take a certain ""Eustache Dauger"" to the prison of Pignerol.Marcel Pagnol identifies this prisoner as the accomplice of Roux previously named "Martin", and later to be the famous prisoner in the iron mask.This is clearly a false name in order to conceal the real identity of the prisoner.