"There have been three robberies in all," said the colonel, "and they have been exactly alike.
"In every case my daughter has left some articles of jewelry on the dressing-table in her bed-room, and one of them has vanished. Never more than one at a time.
"Twice it happened while she was in the adjoining room. The bed-room door which opens into the hall was locked on these occasions.
"The third time she was in the hall, talking with my nephew. He was standing in the upper hall, leaning over the banister rail. They were discussing a plan for a drive out into the country. Quite a party was to go.
"Horace had just received word from a gentleman whom they had invited that he would be unable to go. He had read the note in his room, and he called downstairs to my daughter to tell her about it.
"That was how they happened to be standing in the hall. Presently she went back into her room, and almost immediately noticed that a small locket set with diamonds had been taken.
"She screamed, and Horace and I came running to her room. We searched it thoroughly.
"There was nobody there. The door between the bedroom and the sitting-room was open, but the other door of the sitting-room, which opens into the old portion of the house, was locked and bolted on the inside.
"Now, I submit to you, Mr. Carter, whether in that case any other way of entrance or exit was possible except by the windows."
"I'm bound to admit," responded Nick, "that if the doors were in the condition you describe, no person could have entered or left those rooms except by the windows."