"By Jove, that's very clever, very clever indeed!" exclaimed Galloway. He picked up a magnifying glass which was lying on the table, and closely examined the dirty piece of white paper which Colwyn had found at the mouth of the pit. "It was once a Treasury note, sure enough--the watermark is unmistakable. You've scored a point there that I couldn't have made, and I'm man enough to own up to it. You see more deeply into things than I do, Mr. Colwyn. And I'm willing to admit that you've made some new and interesting discoveries about this case, though in my opinion you are inclined to read too much into them. But I certainly think they ought to be investigated further. If Penreath's statement to you this morning is true, Benson is the murderer, and there has been a miscarriage of justice. But what makes me doubt the truth of it is Penreath's refusal to speak before. I mistrust confessions made out at the last moment. And his explanation that he kept silence to save the girl strikes me as rather thin. It is too quixotic." "There is more than that in it," replied Colwyn. "He had a double motive. Penreath heard Sir Henry Durwood depose at the trial that he believed him to be suffering from epilepsy." "How does that constitute a second motive?" "In this way. Penreath has a highly-strung, introspective temperament. He went to the front from a high sense of duty, but he was temperamentally unfit for the ghastly work of modern warfare, and broke down under the strain. Men like Penreath feel it keenly when they are discharged through shell-shock. They feel that the carefully hidden weaknesses of their temperaments have been dragged out into the light of day, and imagine they have been branded as cowards in the eyes of their fellow men. I suspect that the real reason why Penreath left London and sought refuge in Norfolk under another name was because he had been discharged from the Army through shell-shock. He wanted to get away from London and hide himself from those who knew him. To his wounded spirit the condolences of his friends would be akin to taunts and sneers. When Sir Henry Durwood questioned him he was careful to conceal the fact that he had been a victim of shell-shock. As a matter of fact, Penreath's behaviour in the breakfast room that morning was nothing more than the effects of the air raid on his disordered nerves, but he would sooner have died than admit that to strangers. After listening to the evidence for the defence at the trial, he came to the conclusion that he was an epileptic as well as a neurasthenic. He might well believe that life held little for him in these circumstances, and that conviction would strengthen him in his determination to sacrifice his life as a thing of little value for the girl he loved." "If that is true he must be a very manly young fellow," said the chief constable. "Supposing it is true, what is to be done?" asked Galloway, earnestly. "Penreath has been tried and convicted for the murder."