“You tell me this: Was your statement about the loss of the locket on that night true?”

Colonel Domlio did not reply. He seemed to be weighing some problem of overwhelming difficulty. French waited patiently, wondering how far his bluff would carry. At last the colonel spoke.

“I have lied to the sergeant and to you, Inspector, with what I now believe was a mistaken motive. I have been turning over the matter in my mind and I see that I have no alternative but to tell you the truth now or to suffer arrest. Possibly things have gone so far that this cannot be avoided. At all events, I will tell you everything.”

“You are not forgetting my warning, Colonel Domlio?”

“I am not forgetting it. If I am acting foolishly it is my own lookout. I tried to put you off, Inspector, to save bringing Mrs. Berlyn’s name further into the matter, because, though there was nothing against her character, I was sure you would have bothered her with annoying questions. But, though I thought it right to lie with this object, I don’t feel like risking prison for it.”

“I follow you,” said French.

“You will remember then what I told you about Mrs. Berlyn, that she had been seeing a good deal first of Pyke and then of myself. I’m sorry to have to drag this in again, but otherwise you wouldn’t understand the situation.

“About—let me see—four months before the tragedy Mrs. Berlyn came out here one afternoon. She said that she had been in London to a lecture on entomology and that she had been so much interested that she had read one or two books on the subject. She said that she knew I was doing some research in it and she wondered whether I would let her come and help me and so learn more. I naturally told her I should be delighted, and she began to come out here quite often. On different occasions she has accompanied me on the moor while I was searching for specimens, and she has spent several afternoons with me in my library mounting butterflies and learning to use the microscope. This went on until the day of the tragedy.”

Colonel Domlio paused, squared his shoulders, and continued:

“On that morning I had received by post a letter addressed in a strange hand and marked ‘Personal.’ It was signed ‘X.Y.Z.’ and said that the writer happened to be walking about four P.M. on the previous Tuesday in the Upper Merton glen at a certain point which he described; that he had seen me with Mrs. Berlyn in my arms; that, having a camera, he had at once taken two photographs, one of which had come out; and that if I cared to have the negative he would sell it for fifty pounds. If I wished to negotiate I was to meet him on the Chagford–Gidleigh road at the gate of Dobson’s Spinney at one o’clock that night. Should I not turn up, the writer would understand that I was not interested and would take his picture to Mrs. Berlyn, who, he thought, would prefer to deal rather than have it handed to Mr. Berlyn.