"What—what has happened?"

    "Nothing," said Harvey Froyant sharply.

    They came to the house soon after, Jack carrying the visitor's bag. He was not impressed by the big man's appearance. His voice was coarse, his manner familiar, and Jack wondered what association this uncouth specimen of humanity could have with his father.

    They were nearing the house when suddenly and for no obvious reason the stout Mr. Marl emitted a frightened squeal and leapt back. There was no doubt of his fear. It was written visibly in the blanched cheeks and the quivering lips of the man, who was shaking from head to foot. Jack could only look at him in astonishment—and even Harvey Froyant was startled into an interest.

    "What the hell is wrong with you, Marl?" he asked savagely.

    His own nerves were on edge, and the sight of the big man's undisguised terror was a further strain which he could scarcely endure.

    "Nothin'—nothin'," muttered Marl huskily. "I've been—"

    "Drinking, I should think," snapped Froyant.

    After seeing the man into the house Jack hurried off in search of Derrick Yale. He discovered the detective in the shrubbery sitting in a big cane chair, his chin upon his breast, his arms folded, a characteristic attitude of his. Yale looked up at the sound of the young man's footsteps. "I can't tell you," he said, before Jack had framed his question, and then, seeing the look of astonishment on his face, he laughed. "You were going to ask me what scared Marl, weren't you?"

    "I came with that intention," laughed Jack. "What an extraordinary fellow you are, Mr. Yale! Did you see his extraordinary exhibition of funk?"

    Derrick Yale nodded. "I saw him just before he had his shock," he said. "You can see the field path from here." He frowned. "He reminds me of somebody," he said slowly, "yet I cannot for the life of me tell who it is. Is he a frequent visitor here? Your father told me he was coming, and I guessed it was he."

    Jack shook his head. "This is the first time I've seen him," he said. "I remember now, though, that father and Froyant have had some business dealings with a man named Marl—Dad mentioned him one day. I think he is a land speculator. Father is rather interested in land just now. By the way, I have seen the mark of the Crimson Circle," he added, and described the newly-painted "O" he had found on the elm. Instantly Yale lost interest in Mr. Marl. "It was not on the tree when I went down into the valley," said Jack. "I'll swear to that. It must have been painted whilst I was talking to—to a friend. The trunk is out of sight from the boundary fence, and it was quite possible for somebody to have painted the sign without being seen. What does it mean, Mr.