Herr Eberhard

In the novel The Seven Dials Mystery, Herr Eberhard is a German inventor who had invented a process which could make a wire as strong as a bar of steel, which promised to be very useful for the production of lighter and faster aircraft. His invention had been rejected by the German government who pointed out some flaw. Eberhard fixed the problem but was disgruntled by his government's attitude and decided to sell his secret to the British government. A secret meeting had been arrange at Wyvern Abbey with Sir Stanley Digby, the air minister, for the negotiations. There, his "formula" also became the target of an attempted theft.

Bill Eversleigh who had been told by his Foreign Office superiors to entertain Herr Eberhard (at that time he didn't know about his importance), told |Bundle that his bosses seemed to be making a big fuss about him. Bill described Eberhard as "perfectly poisonous", unlike embassy officials who were usually polite. He "sucks in soup and eats peas with a knife" and kept biting his fingernails.

If Bundle had the image of an eccentric old professor, she would soon be put right. He is younger than she had imagined, thirty-three or thirty-four. She notes that he is ill-at-ease and boorish but his mannerisms such as gnawing fingernails seem to arise from only from nervousness. He looks "thin and weedy ... anaemic and delicate". His blue eyes are shy rather than furtive and altogether his personality is not an unpleasing one.