For The Love of Ciphers: Félix-Marie Delastelle

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The French cryptographer Félix-Marie Delastelle was born in 1850 and died in 1902. For most of his life, he worked as a bonded warehouseman at a local port. After his retirement in 1900, he published a 50-page book named Traité Élémentaire de Cryptographie. His love of creating ciphers was basically his hobby, and…