The man in the corner called for another glass of milk, and drank it down slowly before he resumed:

"Now Lord Arthur lives mostly abroad," he said. "His poor, suffering wife died the day after he was liberated by the magistrate. She never recovered consciousness even sufficiently to hear the joyful news that the man she loved so well was innocent after all.

"Mystery!" he added as if in answer to Polly's own thoughts. "The murder of that man was never a mystery to me. I cannot understand how the police could have been so blind when every one of the witnesses, both for the prosecution and defence, practically pointed all the time to the one guilty person. What do you think of it all yourself?"

"I think the whole case so bewildering," she replied, "that I do not see one single clear point in it."

"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.

"In order to go into the smoking-room she must have crossed the hall; she must have seen Lavender. In that brief interval she must have realized that the man was persistent, and therefore a living danger to her husband. Remember, women have done strange things; they are a far greater puzzle to the student of human nature than the sterner, less complex sex has ever been. As I argued before — as the police should have argued all along — why did Lord Arthur deliberately accuse an innocent man of murder if not to shield the guilty one?

"Remember, Lady Arthur may have been discovered; the man, George Higgins, may have caught sight of her before she had time to make good her retreat. His attention, as well us that of the constables, had to be diverted. Lord Arthur acted on the blind impulse of saving his wife at any cost."

"She may have been met by Colonel McIntosh," argued Polly.

"Perhaps she was," he said. "Who knows? The gallant colonel had to swear to his friend's innocence. He could do that in all conscience — after that his duty was accomplished. No innocent man was suffering for the guilty. The knife which had belonged to Lord Arthur would always save George Higgins. For a time it had pointed to the husband; fortunately never to the wife. Poor thing, she died probably of a broken heart, but women when they love, think only of one object on earth — the one who is beloved.

"To me the whole thing was clear from the very first. When I read the account of the murder — the knife! stabbing! — bah! Don't I know enough of English crime not to be certain at once that no Englishman, be he ruffian from the gutter or be he Duke's son, ever stabs his victim in the back. Italians, French, Spaniards do it, if you will, and women of most nations. An Englishman's instinct is to strike and not to stab. George Higgins or Lord Arthur Skelmerton would have knocked their victim down; the woman only would lie in wait till the enemy's back was turned. She knows her weakness, and she does not mean to miss.

"Think it over. There is not one flaw in my argument, but the police never thought the matter out — perhaps in this case it was as well."

He had gone and left Miss Polly Burton still staring at the photograph of a pretty, gentle-looking woman, with a decided, wilful curve round the mouth, and a strange, unaccountable look in the large pathetic eyes; and the little journalist felt quite thankful that in this case the murder of Charles Lavender the bookmaker — cowardly, wicked as it was — had remained a mystery to the police and the public.