Jules Verne called "The Cryptogram" that she copied the cypher in which she wrote her messages (in invisible ink on linen handkerchiefs and rags), and she had an audacity of invention in numberless small tricks and plots which constantly broke through the meshes of the German network of military police.
"She had a contempt for their stupidity," said the Reverend Mother. "Called them dunderheads, and one strange word of which I do not know the meaning—'yobs'—and I trembled at the risks she took."
She lived with one maid in two rooms on the ground floor of a house near the Jardin d'Eté, the rest of the house being used as the headquarters of the German Intelligence Section of the Northern District. All day long officers went in and out, and by day and night there were always sentries at the door. Yet it was there that was established also the headquarters of the Rescue Committee. It was on account of her Irish name and parentage that Eileen O'Connor was permitted to remain in the two rooms to the left of the courtyard, entered by a separate door. The German Kommandant was a man who firmly believed that the Irish nation was ready to break out into revolt against the English, and that all Irish—men and women—hated the British Empire as much as any Prussian. Eileen O'Connor played up to this idée fixe, saw the value of it as a wonderful means of camouflage, lent the Kommandant books on Irish history dealing with the injustice of England to Ireland (in which she firmly believed as a staunch Nationalist), and educated him so completely to the belief that she was anti-English (as she was in politics, though not in war) that he had no doubt of her.
Here the Reverend Mother made a remark which seemed to illuminate Eileen O'Connor's story, as well as her own knowledge of human nature.
