Étienne Bazeries (21 August 1846 Port Vendres – 7 November 1931 Noyon) was a French military cryptanalyst active between 1890 and the First World War. He is best known for developing the "Bazeries Cylinder", an improved version of Thomas Jefferson's cipher cylinder. It was later refined into the US Army M-94 cipher device. Historian David Kahn describes him as "the great pragmatist of cryptology. His theoretical contributions are negligible, but he was one of the greatest natural cryptanalysts the science has seen." (Kahn 1996, p244)
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