A Turning Grille from the Anchestral Castle of the Dutch Stadtholders

1 Introduction ADDRESS ABSTRACT KEYWORDS Karl de Leeuw and Hans van der Meer A Turning Grille from the Ancestral Castle of the Dutch Stadtholders We are indebted to H.M. the Queen of the Netherlands for granting permission to do research in the Royal Archive. Published in: Cryptologia, April 1995, Volume XIX, number 2, pp. 153--165. : Faculteit Wiskunde en Informatica UVA, Plantage Muidergracht 24, 1018 TV Amsterdam NETHERLANDS. : In the archive of the Dutch Stadtholder William V an undated, unsolved message of unknown origin was found. This message is solved and placed in its historical context by correlating the contents of the message with known historical facts. It turns out to be an early example of a turning grille belonging to the correspondence of Stadtholder William IV. : Cryptanalysis, eighteenth century, Dutch history, Stadtholder William IV, transposition cipher, turning grille. The early history of cryptography cannot be based solely on an analysis of sources. Tempting..