"You don't?" he said excitedly, while the bony fingers fidgeted again with that inevitable bit of string. "You don't see that there is one point clear which to me was the key of the whole thing? "Lavender was murdered, wasn't he? Lord Arthur did not kill him. He had, at least, in Colonel McIntosh an unimpeachable witness to prove that he could not have committed that murder--and yet," he added with slow, excited emphasis, marking each sentence with a knot, "and yet he deliberately tries to throw the guilt upon a man who obviously was also innocent. Now why?" "He may have thought him guilty." "Or wished to shield or cover the retreat of _one he knew to be guilty_." "I don't understand." "Think of someone," he said excitedly, "someone whose desire would be as great as that of Lord Arthur to silence a scandal round that gentleman's name. Someone who, unknown perhaps to Lord Arthur, had overheard the same conversation which George Higgins related to the police and the magistrate, someone who, whilst Chipps was taking Lavender's card in to his master, had a few minutes' time wherein to make an assignation with Lavender, promising him money, no doubt, in exchange for the compromising bills." "Surely you don't mean--" gasped Polly. "Point number one," he interrupted quietly, "utterly missed by the police. George Higgins in his deposition stated that at the most animated stage of Lavender's conversation with Lord Arthur, and when the bookmaker's tone of voice became loud and threatening, a voice from the top of the steps interrupted that conversation, saying: 'Your tea is getting cold.'" "Yes--but--" she argued. "Wait a moment, for there is point number two. That voice was a lady's voice. Now, I did exactly what the police should have done, but did not do. I went to have a look from the racecourse side at those garden steps which to my mind are such important factors in the discovery of this crime. I found only about a dozen rather low steps; anyone standing on the top must have heard every word Charles Lavender uttered the moment he raised his voice." "Even then--" "Very well, you grant that," he said excitedly. "Then there was the great, the all-important point which, oddly enough, the prosecution never for a moment took into consideration. When Chipps, the footman, first told Lavender that Lord Arthur could not see him the bookmaker was terribly put out; Chipps then goes to speak to his master; a few minutes elapse, and when the footman once again tells Lavender that his lordship won't see him, the latter says 'Very well,' and seems to treat the matter with complete indifference. "Obviously, therefore, something must have happened in between to alter the bookmaker's frame of mind. Well! What had happened? Think over all the evidence, and you will see that one thing only had occurred in the interval, namely, Lady Arthur's advent into the room.