There was a sharp cry. It came from Mrs. Pond, who, with Horace, had approached during this scene.
"Why, there's one of my diamond pins!" she exclaimed. "How on earth did it come to be there?"
Well, if Mrs. Pond was surprised, she wasn't a bit more so than Nick Carter.
The pin referred to was the one which had been stolen from the cushion in Mrs. Pond's dressing-room not ten minutes before.
"Why, this is impossible," cried Mrs. Pond. "I left that pin with the two others like it in my room."
Without saying another word, she turned and ran into the house.
Almost immediately her voice was heard in the hall.
"It's gone!" she cried. "It's been taken out of my bedroom."
She appeared at the door with a very white face.
But her excitement was nothing to that of Mrs. Stevens.
Nick dropped the role of detective and assumed that of doctor in less than a second.
When he had saved Mrs. Stevens from an attack of hysterics, he said:
"I was aware that that pin had been taken. It was done while I was in your room, Mrs. Pond. The circumstances were exactly the same as those attending the other robberies."
"But I did not put it in the box," exclaimed Mrs. Stevens. "It was not among the jewels which I found."
She turned to Colonel Richmond. Her face was ghastly pale.
"I have scorned your belief," she said; "but now I am convinced. No mortal being could have done this thing."
"What do you say to that, Mr. Carter?" cried the colonel, with flashing eyes.
"I would like to ask a few questions," rejoined Nick. "Were you alone when you put those jewels into the box?"
"I was."
"Has it been in your possession ever since?"
"It has not been out of my care."
"Did you tell anybody about the finding of the jewels?"
"Nobody."
"Please describe everything that happened after you found them."
"I was, of course, greatly agitated. I did not know what to do. For some time I sat staring at the jewels and trying to think what was my proper course.
"At last I took this box from a drawer of my dressing-table and put the jewels into it.
"Then I called to the servant who was in the dining-room, and asked her to see that the carriage was got ready, for though it is a long drive, I had resolved to make it, because I felt safer in that way."
"Did you go out of your room to call the girl?"
"Only into the hall."
"Who could have got into your room while you were out?"
"Nobody."
"Where was your daughter?"
"In her own room."
"How do you know?"
"I called to her after I had dressed, and she answered me. I told her that I was going to drive over here, and she was very much surprised. I did not tell her why."
"Did you meet anybody on the way over who spoke to you or came to the side of the carriage?"
"Nobody."
"That is all I wish to ask."
In fact, Nick had no more questions. He was really at a loss for an explanation of this strange occurrence.
If the pin had been taken from the room, by a person concealed in the house, it might have been possible that that person had escaped from the grounds unseen, and had given it to Mrs. Stevens.
There was hardly time for such a trick to have been done, but in so strange a case every possibility was to be considered.
If such a thing had been done, it must have been very near to the house.
The thief must have known when Mrs. Stevens was coming, or she must have waited for him just outside the colonel's grounds.
There was a place where the road was heavily fringed with trees, not more than a hundred yards from the colonel's gate.
The trick must have been done there, if at all.
Nick resolved to settle this small point, if possible, immediately.
It was of no use to ask the man who had driven Mrs. Stevens' horse. Of course, he would lie, if there was any need of it.
So Nick excused himself from the group on the pretext that he was going to search Mrs. Pond's rooms again.
He remembered that just after Mrs. Stevens had arrived, a wagon belonging to the colonel had driven into the grounds. He quietly looked up the two servants who had been in this wagon. They told him that they remembered seeing Mrs. Stevens drive up.
She had passed them on the road. They had had her carriage in sight for a mile before it turned into Colonel Richmond's grounds.