The Solving of a Fleissner Grille during an Exercise by the Royal Netherlands Army in 1913

In 1885 the General Staff of the Royal Netherlands Army had adopted a variant of the turning grille devised by Edouard Fleissner von Wostrowitz as a means for encrypting messages, exchanged by telegraph between the General Headquarters and commanders in the field. Some staffmembers harbored serious doubts about the security of this device, however, and during a military exercise in 1913 it was solved with surprising ease by an army captain. The matter was investigated by a committee of staff officers, concluding that the army lacked the expertise to judge matters like this. It recommended the training of a staff officer for this purpose in particular. The outbreak of the First World War was to speed up the decision process, but – against all odds – the newly trained experts were not drawn from the ranks that had demonstrated their talent for code breaking a year earlier, because these were destined to follow different career paths altogether.