How a Piece of Carbon Paper Fooled the Germans

Colonel Arthur L. Conger of the American Expeditionary Force shut himself inside his hotel room. Carefully placing a fresh carbon between two sheets of paper, the colonel began typing a description of a planned major U.S. offensive through the Belfort Gap and toward the Black Forest in Germany. Finishing the document, Conger examined the carbon. Held to the light, it would be legible. He then lightly crumpled the telltale sheet and put it in the wastebasket. Folding the original and the copy, he placed both inside his tunic and then went outside for a stroll around the hotel grounds. After returning sometime later, Conger was satisfied to note that the carbon had been removed from the wastebasket. It was August 30, 1918, in Belfort, France, a small town near the German border.