The first conjecture of what till recently seemed to be the troth is contained in a letter dated 1770, written by a baron d'Ileiss to the Journal Encyclopedique. The same is repeated by. Louis Dntens in his Intercepted Correspondence (1789), who declares that there is no point of history better established than the fact that the prisoner with the iron mask was a minister of the duke of Mantua. This minister, count Matthioli, had pledged himself to Louis XIV. to urge his master the duke to deliver up to the French the fortress of Casale, which gave access to the whole of Lombardy. Though largely bribed to maintain the French interests he began to betray them; and Louis XIV., having got conclusive proofs of the treachery, contrived to have Munition lured to the French frontier, secretly arrested, April 23, 1079, and conveyed to the fortress of Pignerol, which was his first prison. The conclusion of D'Heiss and Damns, .that Matthioli was the iron mask, though acute, was only a conjecture. But the documents since discovered and published by M. Roux-Fazillac in his Receeches historiques et critiques sup l'ilomme au Masque de Fee (Par. 1800), by M. Delon in his Histaire de
au _Masque de Fee (Par. 1825), and M. Marius Topin in his Matz with the Iron Mask (1869), seemed to leave little doubt on the subject, and the public had apparently made up its mind that the secret was at last discovered; but a still more recent work by a French officer, M. 'fit. lung. La Virile sue le Masque de Fee (Les Empoison nears) d'apres ties Documents inedits des Archives de la Guerre et depots publics,1664-1703 (Par. 1873), has conclusively shown that Matthioli could not have been the mysterious prisoner, and endeavors to prove—we would almost venture to say, succeeds in proving— that the man in the iron mask was the unknown head of a wide-spread and formidable conspiracy, working in secret for the assassination of Louis XIV. and some of his ablest ministers. The severity of M. lung's labors with reference to this subject will be understood when it is stated that in the course of his researches he had to examine some 1700 volumes of dispatches and reports iu the bureau of the ministry of war.