Dr Jim Beach recently contributed an article for the GCHQ blog, which begins:
At five in the morning on 21 March 1918, Vince Schürhoff woke to the thunderous sound of a bombardment. After many false alarms, the much-anticipated German offensive had begun.
Vince was a twenty-six year-old corporal in the British army’s Royal Engineers (Signal Service). In 1914 he had joined the army as an infantryman and two years later, because he spoke fluent German, was seconded to signals intelligence work.
That day Vince was in command of what their inhabitants called an IToc (aye-tok) station and the army called a listening set post. Using metal probes and long loops of wire, Vince and his comrades could pick up German messages leaking from trench telephone lines or Morse buzzer messages sent through the earth…