For a moment Brereton and the superintendent looked at each other in silence. Then Bent got up from his desk at the other side of the room, and he and the little solicitor came towards them.

"Keep that to yourself, then," muttered Brereton. "We'll talk of it later. It may be of importance."

"Well, there's this much to bear in mind," whispered the superintendent, drawing back a little with an eye on the others. "Nothing of that sort was found on your client! And he'd been out all night. That's worth considering—from his standpoint, Mr. Brereton."

Brereton nodded his assent and turned away with another warning glance. And presently Pett and the superintendent went off, and Bent dropped into his easy chair with a laugh.

"Queer sort of unexpected legacy!" he said. "I wonder if the old man really thought I should be interested in his scrap-book?"

"There may be a great deal that's interesting in it," remarked Brereton, with a glance at the book, which Bent had laid aside on top of a book-case. "Take care of it. Well, what did you think of Mr. Christopher Pett?"

"Cool hand, I should say," answered Bent. "But—what did you think of him?"

"Oh, I've met Mr. Christopher Pett's sort before," said Brereton, drily. "The Dodson & Fogg type of legal practitioner is by no means extinct. I should much like to know a good deal more about his various dealings with Kitely. We shall see and hear more about them, however—later on. For the present there are—other matters."

He changed the subject then—to something utterly apart from the murder and its mystery. For the one topic which filled his own mind was also the very one which he could not discuss with Bent. Had Cotherstone, had Mallalieu anything to do with Kitely's death? That question was beginning to engross all his attention: he thought more about it than about his schemes for a successful defence of Harborough, well knowing that his best way of proving Harborough's innocence lay in establishing another man's guilt.

"One would give a good deal," he said to himself, as he went to bed that night, "if one could get a moment's look into Cotherstone's mind—or into Mallalieu's either! For I'll swear that these two know something—possibly congratulating themselves that it will never be known to anybody else!"

If Brereton could have looked into the minds of either of the partners at this particular juncture he would have found much opportunity for thought and reflection, of a curious nature. For both were keeping a double watch—on the course of events on one hand; on each other, on the other hand. They watched the police-court proceedings against Harborough and saw, with infinite relief, that nothing transpired which seemed inimical to themselves. They watched the proceedings at the inquest held on Kitely; they, too, yielded nothing that could attract attention in the way they dreaded. When several days had gone by and the police investigations seemed to have settled down into a concentrated purpose against the suspected man, both Mallalieu and Cotherstone believed themselves safe from discovery—their joint secret appeared to be well buried with the old detective. But the secret was keenly and vividly alive in their own hearts, and when Mallalieu faced the truth he knew that he suspected Cotherstone, and when Cotherstone put things squarely to himself he knew that he suspected Mallalieu. And the two men got to eyeing each other furtively, and to addressing each other curtly, and when they happened to be alone there was a heavy atmosphere of mutual dislike and suspicion between them.

It was a strange psychological fact that though these men had been partners for a period covering the most important part of their lives, they had next to nothing in common. They were excellent partners in business matters; Mallalieu knew Cotherstone, and Cotherstone knew Mallalieu in all things relating to the making of money. But in taste, temperament, character, understanding, they were as far apart as the poles. This aloofness when tested further by the recent discomposing events manifested itself in a disinclination to confidence. Mallalieu, whatever he thought, knew very well that he would never say what he thought to Cotherstone; Cotherstone knew precisely the same thing with regard to Mallalieu. But this silence bred irritation, and as the days went by the irritation became more than Cotherstone could bear. He was a highly-strung, nervous man, quick to feel and to appreciate, and the averted looks and monosyllabic remarks and replies of a man into whose company he could not avoid being thrown began to sting him to something like madness. And one day, left alone in the office with Mallalieu when Stoner the clerk had gone to get his dinner, the irritation became unbearable, and he turned on his partner in a sudden white heat of ungovernable and impotent anger.

"Hang you!" he hissed between his set teeth. "I believe you think I did that job! And if you do, blast you, why don't you say so, and be done with it?"

Mallalieu, who was standing on the hearth, warming his broad back at the fire, thrust his hands deeply into his pockets and looked half-sneeringly at his partner out of his screwed-up eyes.

"I should advise you to keep yourself cool," he said with affected quietness. "There's more than me'll think a good deal if you chance to let yourself out like that."

"You do think it!" reiterated Cotherstone passionately. "Damn it, d'ye think I haven't noticed it? Always looking at me as if—as if——"

"Now then, keep yourself calm," interrupted Mallalieu. "I can look at you or at any other, in any way I like, can't I? There's no need to distress yourself—I shan't give aught away. If you took it in your head to settle matters—as they were settled—well, I shan't say a word. That is unless—you understand?"

"Understand what?" screamed Cotherstone.

"Unless I'm obliged to," answered Mallalieu. "I should have to make it clear that I'd naught to do with that particular matter, d'ye see? Every man for himself's a sound principle. But—I see no need. I don't believe there'll be any need. And it doesn't matter the value of that pen that's shaking so in your hand to me if an innocent man suffers—if he's innocent o' that, he's guilty o' something else. You're safe with me."

Cotherstone flung the pen on the floor and stamped on it. And Mallalieu laughed cynically and walked slowly across to the door.

"You're a fool, Cotherstone," he said. "Go on a bit more like that, and you'll let it all out to somebody 'at 'll not keep secrets as I can. Cool yourself, man, cool yourself!"

"Hang you!" shouted Cotherstone. "Mind I don't let something out about you! Where were you that night, I should like to know? Or, rather, I do know! You're no safer than I am! And if I told what I do know——"

Mallalieu, with his hand on the latch, turned and looked his partner in the face—without furtiveness, for once.

"And if you told aught that you do, or fancy you know," he said quietly, "there'd be ruin in your home, you soft fool! I thought you wanted things kept quiet for your lass's sake? Pshaw!—you're taking leave o' your senses!"

He walked out at that, and Cotherstone, shaking with anger, relapsed into a chair and cursed his fate. And after a time he recovered himself and began to think, and his thoughts turned instinctively to Lettie.

Mallalieu was right—of course, he was right! Anything that he, Cotherstone, could say or do in the way of bringing up the things that must be suppressed would ruin Lettie's chances. So, at any rate, it seemed to him. For Cotherstone's mind was essentially a worldly one, and it was beyond him to believe that an ambitious young man like Windle Bent would care to ally himself with the daughter of an ex-convict. Bent would have the best of excuses for breaking off all relations with the Cotherstone family if the unpleasant truth came out. No!—whatever else he did, he must keep his secret safe until Bent and Lettie were safely married. That once accomplished, Cotherstone cared little about the future: Bent could not go back on his wife. And so Cotherstone endeavoured to calm himself, so that he could scheme and plot, and before night came he paid a visit to his doctor, and when he went home that evening, he had his plans laid.

Bent was with Lettie when Cotherstone got home, and Cotherstone presently got the two of them into a little snuggery which he kept sacred to himself as a rule. He sat down in his easy chair, and signed to them to sit near him.

"I'm glad I found you together," he said. "There's something I want to say. There's no call for you to be frightened, Lettie—but what I've got to say is serious. And I'll put it straight—Bent'll understand. Now, you'd arranged to get married next spring—six months hence. I want you to change your minds, and to let it be as soon as you can."

He looked with a certain eager wistfulness at Lettie, expecting to see her start with surprise. But fond as he was of her, Cotherstone had so far failed to grasp the later developments of his daughter's character. Lettie Cotherstone was not the sort of young woman who allows herself to be surprised by anything. She was remarkably level-headed, cool of thought, well able to take care of herself in every way, and fully alive to the possibilities of her union with the rising young manufacturer. And instead of showing any astonishment, she quietly asked her father what he meant.

"I'll tell you," answered Cotherstone, greatly relieved to find that both seemed inclined to talk matters quietly over. "It's this—I've not been feeling as well as I ought to feel, lately. The fact is, Bent, I've done too much in my time. A man can work too hard, you know—and it tells on him in the end. So the doctor says, anyhow."

"The doctor!" exclaimed Lettie. "You haven't been to him?"

"Seen him this afternoon," replied Cotherstone. "Don't alarm yourself. But that's what he says—naught wrong, all sound, but—it's time I rested. Rest and change—complete change. And I've made up my mind—I'm going to retire from business. Why not? I'm a well-to-do man—better off than most folks 'ud think. I shall tell Mallalieu tomorrow. Yes—I'm resolved on it. And that done, I shall go and travel for a year or two—I've always wanted to go round the world. I'll go—that for a start, anyway. And the sooner the better, says the doctor. And——" here he looked searchingly at his listeners—"I'd like to see you settled before I go. What?"

Lettie's calm and judicial character came out in the first words she spoke. She had listened carefully to Cotherstone; now she turned to Bent.

"Windle," she said, as quietly as if she were asking the most casual of questions, "wouldn't it upset all your arrangements for next year? You see, father," she went on, turning to Cotherstone, "Windle had arranged everything. He was going to have the whole of the spring and summer away from business; we were going on the Continent for six months. And that would have to be entirely altered and——"

"We could alter it," interrupted Bent. He was watching Cotherstone closely, and fancying that he saw a strained and eager look in his face, he decided that Cotherstone was keeping something back, and had not told them the full truth about his health.

"It's all a matter of arrangement. I could arrange to go away during the winter, Lettie."

"But I don't want to travel in winter," objected Lettie. "Besides—I've made all my arrangements about my gowns and things."

"That can be arranged, too," said Bent. "The dressmaker can work overtime."

"That'll mean that everything will be hurried—and spoiled," replied Lettie. "Besides, I've arranged everything with my bridesmaids. They can't be expected to——"

"We can do without bridesmaids," replied Bent, laying his hand on Lettie's arm. "If your father really feels that he's got to have the rest and the change he spoke of, and wants us to be married first, why, then——"

"But there's nothing to prevent you having a rest and a change now, father," said Lettie. "Why not? I don't like my arrangements to be altered—I had planned everything out so carefully. When we did fix on next spring, Windle, I had only just time as it was!"

"Pooh!" said Bent. "We could get married the day after tomorrow if we wanted! Bridesmaids—gowns—all that sort of tomfoolery, what does it matter?"

"It isn't tomfoolery," retorted Lettie. "If I am to be married I should like to be married properly."

She got up, with a heightened colour and a little toss of her head, and left the room, and the two men looked at each other.

"Talk to her, my lad," said Cotherstone at last. "Of course, girls think such a lot of—of all the accompaniments, eh?"

"Yes, yes—it'll be all right," replied Bent. He tapped Cotherstone's arm and gave him a searching look. "You're not keeping anything back—about your health, are you?" he asked.

Cotherstone glanced at the door and sank his voice to a whisper."It's my heart!" he answered. "Over-strained—much over-strained, the doctor says. Rest and change—imperative! But—not a word to Lettie, Bent. Talk her round—get it arranged. I shall feel safer—you understand?"

Bent was full of good nature, and though he understood to the full—it was a natural thing, this anxiety of a father for his only child. He promised to talk seriously to Lettie at once about an early wedding. And that night he told Brereton of what had happened, and asked him if he knew how special licences can be got, and Brereton informed him of all he knew on that point—and kept silence about one which to him was becoming deeply and seriously important.