"The box may have been locked when you found it, but it seems equally certain that it was also empty," said Colwyn. He alone of the excited group was cool enough to estimate the awkward possibilities of this discovery. "How was it that the detectives did not open the jewel-case on the night of the murder, so as to make quite sure that the necklace had not been stolen?" "I took the necklace downstairs and locked it away before the police arrived," said Miss Heredith tearfully. "When Detective Caldew came he asked me if anything was missing from Violet's bedroom, and I told him no. Of course, I did not dream of anything like this. Oh, how I wish now that I had opened the jewel-case at the time. But I never thought. I tried the case and found it locked, so I thought it had not been touched." "Really, I am more to blame than Miss Heredith," interposed Musard hurriedly. "I saw the jewel-case first, and I should have thought of having it opened." "It is a pity you did not inform the detectives about the case," said Colwyn. His face was grave as he realized how completely the police had been led astray in their original investigations by the misunderstanding which had concealed an important fact. "But first let us make sure that the jewel-case was empty when it was brought downstairs. How many people have access to this safe, Miss Heredith? Is there more than one key?" "There is only one key," she replied. "And that has been in my possession since the night of the murder." "That disposes of that possibility, then. What about Mrs. Heredith's bunch of keys? Have they also been in your possession since she was killed?" "Yes; I kept them in an upstairs drawer, which was locked." "Can you tell me when you last saw the necklace?" Miss Heredith reflected for a moment. "Not for some time," she said. "Violet did not care for it, and rarely wore it." "The necklace was of pink pearls," Musard explained. "Their value was more historical than intrinsic, for they had become tarnished with age, and the setting was old-fashioned. It was for that reason Mrs. Heredith did not like it. I was going to take the pearls to London the following day to arrange to have them skinned and reset." "When I went into poor Violet's room that night to see if she felt well enough to go to the Weynes' I asked her for the necklace," said Miss Heredith. "She replied that she would give it to me in the morning. If she had only given it to me then, she might have been alive to-day." "I should like to hear more about this," said Colwyn. "Please tell me everything."