He lapsed into silence. Grant noticed that his hands were trembling.

"What made you think that the money you say Sorrell left with you was all he had?"

"Because it was the amount he had in his own private account at the bank. It was I who drew it for him more than a week before he was due to sail. He drew it all but a pound."

"Were you in the habit of drawing money for him?"

"No; hardly ever. But that week he was terribly busy settling affairs at the office and clearing up generally."

"Why did he draw it so soon if he did not need it to pay his fare, as he evidently didn't?"

"I don't know, unless he was afraid he wouldn't have enough in the business ac-count to pay off all the accounts. But he had. He didn't leave a ha'penny owing."

"Was business good?"

"Yes; not bad. As good as it ever is in the winter. We do very little National Hunt betting — did, I mean. During the 'flat' it was good enough."

"At the end of the winter would be a lean season with Sorrell, then?"

"Yes."

"And you handed the money to Sorrell — when?"

"Directly I got back from the bank."

"You say you quarrelled with Sorrell about the revolver. Can you prove the revolver was yours?"

"No; how can I? No one knew about it because it was locked up — no one but Bert, I mean. It was loaded, just the way it was when the Armistice came. It wasn't a thing to leave about."

"And what do you suggest that Sorrell wanted it for?"

"I don't know. I haven't the remotest idea. I did think of suicide. It looked like that. But then there was no reason for it."

"When you said to me at Carninnish that in your opinion a woman had killed Sorrell, what did you mean?"

"Well, you see, I knew all Bert's men friends, and he didn't have any girl ones — I mean girls that are more than acquaintances. But I always thought there might have been a woman before I knew him. He was very quiet about the things he cared about, and he wouldn't have told me in any case. I have seen him sometimes get letters in a woman's handwriting, but he never re-marked about them, and Bert wasn't the kind you teased about that sort of thing."

"Has a letter of that sort arrived for him lately — within the past six months, say?"

Lamont thought for a while and said yes, he thought so.

"What kind of writing?"

"Biggish, with very round letters."

"You have read the description of the dagger that killed Sorrell. Have you ever handled one like it?"

"I not only never handled one but I never saw one.

"Have you any suggestions as to who or what this hypothetical woman might have been?"

"No."

"Do you mean to say that you were this man's intimate friend for years — actually lived with him for four years — and yet know nothing of his past?"

"I know quite a lot about his past, but not that. You didn't know Bert or you wouldn't expect him to tell me. He wasn't secretive in ordinary things — only in special things."

"Why was he going to America?"

"I don't know. I told you I thought he hadn't been happy lately. He never was exactly bubbling over, but lately — well, it's been more of an atmosphere than anything you could give a name to."

"Was he going alone?"

"Yes."

"Not with a woman?"

"Certainly not," said Lamont sharply, as if Grant had insulted him or his friend.

"How do you know?"

Lamont hunted round in his mind, evidently at a loss. He was quite obviously facing the possibility for the first time that his friend had intended to go abroad with some one and had not told him. Grant could see him considering the proposition and rejecting it. "I don't know how I know, but I do know. He would have told me that."

"Then you deny having any knowledge as to how Sorrell met his end?"

"I do. Don't you think, if I had any knowledge, I'd tell you all I knew?"

"I expect you would!" said Grant. "The very vagueness of your suspicions is a bad feature in your line of defence." He asked the constable to read out what he had written, and Lamont agreed that it coincided with what he had said, and signed each page with a none too steady hand. As he signed the last he said, "I'm feeling rotten. Can I lie down now?" Grant gave him a draught which he had cadged from the doctor, and in fifteen minutes the prisoner was sleeping the sleep of utter exhaustion, while his captor stayed awake and thought the statement over.

It was an extraordinarily plausible one. It fitted and dovetailed beautifully. Except for its fundamental improbability, it was difficult to fault it. The man had had an explanation for everything. Times and places, even motives fitted. His account of his sup-posed emotions, from the discovery of the loss of the revolver onwards, was a triumph of verisimilitude. Was it possible, even remotely possible, that the man's statement was true? Was this that thousandth case where circumstantial evidence, complete in every particular, was merely a series of accidents, completely unrelated and lying colossally in consequence? But then, the thinness of the man's story — that fundamental improbability! After all, he had had nearly a fortnight to carve out his explanation, plane it, polish it, and make it fit in every particular. It would be a poor wit that would not achieve a tolerably acceptable tale with life itself at stake. That there was no one to check the truth or otherwise of the vital points was at once his misfortune and his advantage. It occurred to Grant that the only way to check Lamont's explanation was to unearth Sorrell's story, for story, Grant felt, there must be. If he could dis-cover that Sorrell really intended suicide, it would go far to substantiate Lamont's story of the purloined revolver and the gift of money. And there Grant pulled himself up. Substantiate Lamont's story? Was there a possibility of such a thing coming to pass? If that were so, his whole case went up in smoke, Lamont was not guilty, and he had arrested the wrong man. But was there within the bounds of possibility a coincidence which would put in one theatre queue two men, both left-handed, both scarred on a finger of that hand, and both acquaintances of the dead man, and therefore his potential murderers? He refused to believe it. It was not the credibility of the man's tale that had thrown dust in his eyes, but the extraordinary credibility of the manner of telling it. And what was that but plausibility!

His mind continued to go round and round the thing. In the man's favour — there he was again! — was the fact that the fingerprints on the revolver and those on the letter containing the money were the same. If the prints he had sent from Carninnish proved to be the same as these, then the man's story was true to that extent. The tale of Sorrell's letters from the feminine source could be checked by application to Mrs. Everett. Mrs. Everett evidently believed Lamont innocent, and had gone to considerable lengths in support of her conviction; but then she was prejudiced, and therefore not a competent judge.

Supposing, then, that the man's tale was a concocted one, what combination of circumstances would explain his murdering Sorrel? Was it possible that he had resented his friend's departure without offering to help him, so much that he could commit murder for it? But he had Sorrell's money in his possession. If he had obtained that money before Sorrell died, he would have no reason for killing him. And if he had not, then the money would have been found in Sorrell's possession. Or suppose he had obtained the money by stealing his friend's pocketbook during that afternoon, he would still have no urge to murder, and there would have been every reason to keep away from the queue. The more Grant thought of it, the more impossible it became to invent a really good theory as to why Lamont should have murdered Sorrell. Most of all in his favour was that he should have come to so public a place as a theatre queue to expostulate with his friend about something. It was not a usual preliminary to intended murder. But perhaps the murder had not been intended. Lamont did not give the impression of a man who would intend murder for very long at a time. Had the quarrel been not over the revolver at all but about something more bitter? Was there a woman in the case after all, for instance? For no reason Grant had a momentary recollection of Lamont's face when the Dinmont girl had gone out of the room as if he was not there, and the tones of his voice when he was telling of Sorrell's suspected romance, and he dismissed that theory.