For the first time in twenty years, I kept my bed that day. Liddy was alarmed to the point of hysteria, and sent for Doctor Stewart just after breakfast. Gertrude spent the morning with me, reading something--I forget what. I was too busy with my thoughts to listen. I had said nothing to the two detectives. If Mr. Jamieson had been there, I should have told him everything, but I could not go to these strange men and tell them my niece had been missing in the middle of the night; that she had not gone to bed at all; that while I was searching for her through the house, I had met a stranger who, when I fainted, had carried me into a room and left me there, to get better or not, as it might happen.

The whole situation was terrible: had the issues been less vital, it would have been absurd. Here we were, guarded day and night by private detectives, with an extra man to watch the grounds, and yet we might as well have lived in a Japanese paper house, for all the protection we had.

And there was something else: the man I had met in the darkness had been even more startled than I, and about his voice, when he muttered his muffled exclamation, there was something vaguely familiar. All that morning, while Gertrude read aloud, and Liddy watched for the doctor, I was puzzling over that voice, without result.

And there were other things, too. I wondered what Gertrude's absence from her room had to do with it all, or if it had any connection. I tried to think that she had heard the rapping noises before I did and gone to investigate, but I'm afraid I was a moral coward that day. I could not ask her.

Perhaps the diversion was good for me. It took my mind from Halsey, and the story we had heard the night before. The day, however, was a long vigil, with every ring of the telephone full of possibilities. Doctor Walker came up, some time just after luncheon, and asked for me.

"Go down and see him," I instructed Gertrude. "Tell him I am out--for mercy's sake don't say I'm sick. Find out what he wants, and from this time on, instruct the servants that he is not to be admitted. I loathe that man."

Gertrude came back very soon, her face rather flushed.

"He came to ask us to get out," she said, picking up her book with a jerk. "He says Louise Armstrong wants to come here, now that she is recovering"

"And what did you say?"

"I said we were very sorry we could not leave, but we would be delighted to have Louise come up here with us. He looked daggers at me. And he wanted to know if we would recommend Eliza as a cook. He has brought a patient, a man, out from town, and is increasing his establishment--that's the way he put it."

"I wish him joy of Eliza," I said tartly. "Did he ask for Halsey?"

"Yes. I told him that we were on the track last night, and that it was only a question of time. He said he was glad, although he didn't appear to be, but he said not to be too sanguine."

"Do you know what I believe?" I asked. "I believe, as firmly as I believe anything, that Doctor Walker knows something about Halsey, and that he could put his finger on him, if he wanted to."

There were several things that day that bewildered me. About three o'clock Mr. Jamieson telephoned from the Casanova station and Warner went down to meet him. I got up and dressed hastily, and the detective was shown up to my sitting-room.

"No news?" I asked, as he entered. He tried to look encouraging, without success. I noticed that he looked tired and dusty, and, although he was ordinarily impeccable in his appearance, it was clear that he was at least two days from a razor.

"It won't be long now, Miss Innes," he said. "I have come out here on a peculiar errand, which I will tell you about later. First, I want to ask some questions. Did any one come out here yesterday to repair the telephone, and examine the wires on the roof?"

"Yes," I said promptly; "but it was not the telephone. He said the wiring might have caused the fire at the stable. I went up with him myself, but he only looked around."

Mr. Jamieson smiled.

"Good for you!" he applauded. "Don't allow any one in the house that you don't trust, and don't trust anybody. All are not electricians who wear rubber gloves."

He refused to explain further, but he got a slip of paper out of his pocketbook and opened it carefully.

"Listen," he said. "You heard this before and scoffed. In the light of recent developments I want you to read it again. You are a clever woman, Miss Innes. Just as surely as I sit here, there is something in this house that is wanted very anxiously by a number of people. The lines are closing up, Miss Innes."

The paper was the one he had found among Arnold Armstrong's effects, and I read it again:

"----by altering the plans for----rooms, may be possible. The best way, in my opinion, would be to----the plan for----in one of the----rooms----chimney."

"I think I understand," I said slowly. "Some one is searching for the secret room, and the invaders--"

"And the holes in the plaster--"

"Have been in the progress of his--"

"Or her--investigations."

"Her?" I asked.

"Miss Innes," the detective said, getting up, "I believe that somewhere in the walls of this house is hidden some of the money, at least, from the Traders' Bank. I believe, just as surely, that young Walker brought home from California the knowledge of something of the sort and, failing in his effort to reinstall Mrs. Armstrong and her daughter here, he, or a confederate, has tried to break into the house. On two occasions I think he succeeded."

"On three, at least," I corrected. And then I told him about the night before. "I have been thinking hard," I concluded, "and I do not believe the man at the head of the circular staircase was Doctor Walker. I don't think he could have got in, and the voice was not his."

Mr. Jamieson got up and paced the floor, his hands behind him.

"There is something else that puzzles me," he said, stepping before me. "Who and what is the woman Nina Carrington? If it was she who came here as Mattie Bliss, what did she tell Halsey that sent him racing to Doctor Walker's, and then to Miss Armstrong? If we could find that woman we would have the whole thing."

"Mr. Jamieson, did you ever think that Paul Armstrong might not have died a natural death?"

"That is the thing we are going to try to find out," he replied. And then Gertrude came in, announcing a man below to see Mr. Jamieson.

"I want you present at this interview, Miss Innes," he said. "May Riggs come up? He has left Doctor Walker and he has something he wants to tell us."

Riggs came into the room diffidently, but Mr. Jamieson put him at his ease. He kept a careful eye on me, however, and slid into a chair by the door when he was asked to sit down.

"Now, Riggs," began Mr. Jamieson kindly. "You are to say what you have to say before this lady."

"You promised you'd keep it quiet, Mr. Jamieson." Riggs plainly did not trust me. There was nothing friendly in the glance he turned on me.

"Yes, yes. You will be protected. But, first of all, did you bring what you promised?"

Riggs produced a roll of papers from under his coat, and handed them over. Mr. Jamieson examined them with lively satisfaction, and passed them to me. "The blue-prints of Sunnyside," he said. "What did I tell you? Now, Riggs, we are ready."

"I'd never have come to you, Mr. Jamieson," he began, "if it hadn't been for Miss Armstrong. When Mr. Innes was spirited away, like, and Miss Louise got sick because of it, I thought things had gone far enough. I'd done some things for the doctor before that wouldn't just bear looking into, but I turned a bit squeamish."

"Did you help with that?" I asked, leaning forward.

"No, ma'm. I didn't even know of it until the next day, when it came out in the Casanova Weekly Ledger. But I know who did it, all right. I'd better start at the beginning.

"When Doctor Walker went away to California with the Armstrong family, there was talk in the town that when he came back he would be married to Miss Armstrong, and we all expected it. First thing I knew, I got a letter from him, in the west. He seemed to be excited, and he said Miss Armstrong had taken a sudden notion to go home and he sent me some money. I was to watch for her, to see if she went to Sunnyside, and wherever she was, not to lose sight of her until he got home. I traced her to the lodge, and I guess I scared you on the drive one night, Miss Innes."

"And Rosie!" I ejaculated.

Riggs grinned sheepishly.

"I only wanted to make sure Miss Louise was there. Rosie started to run, and I tried to stop her and tell her some sort of a story to account for my being there. But she wouldn't wait."

"And the broken china--in the basket?"

"Well, broken china's death to rubber tires," he said. "I hadn't any complaint against you people here, and the Dragon Fly was a good car."

So Rosie's highwayman was explained.

"Well, I telegraphed the doctor where Miss Louise was and I kept an eye on her. Just a day or so before they came home with the body, I got another letter, telling me to watch for a woman who had been pitted with smallpox. Her name was Carrington, and the doctor made things pretty strong. If I found any such woman loafing around, I was not to lose sight of her for a minute until the doctor got back.

"Well, I would have had my hands full, but the other woman didn't show up for a good while, and when she did the doctor was home."

"Riggs," I asked suddenly, "did you get into this house a day or two after I took it, at night?"

"I did not, Miss Innes. I have never been in the house before. Well, the Carrington woman didn't show up until the night Mr. Halsey disappeared. She came to the office late, and the doctor was out. She waited around, walking the floor and working herself into a passion. When the doctor didn't come back, she was in an awful way. She wanted me to hunt him, and when he didn't appear, she called him names; said he couldn't fool her. There was murder being done, and she would see him swing for it.

"She struck me as being an ugly customer, and when she left, about eleven o'clock, and went across to the Armstrong place, I was not far behind her. She walked all around the house first, looking up at the windows. Then she rang the bell, and the minute the door was opened she was through it, and into the hall."

"How long did she stay?"

"That's the queer part of it," Riggs said eagerly. "She didn't come out that night at all. I went to bed at daylight, and that was the last I heard of her until the next day, when I saw her on a truck at the station, covered with a sheet. She'd been struck by the express and you would hardly have known her--dead, of course. I think she stayed all night in the Armstrong house, and the agent said she was crossing the track to take the up-train to town when the express struck her."

"Another circle!" I exclaimed. "Then we are just where we started."

"Not so bad as that, Miss Innes," Riggs said eagerly. "Nina Carrington came from the town in California where Mr. Armstrong died. Why was the doctor so afraid of her? The Carrington woman knew something. I lived with Doctor Walker seven years, and I know him well. There are few things he is afraid of. I think he killed Mr. Armstrong out in the west somewhere, that's what I think. What else he did I don't know--but he dismissed me and pretty nearly throttled me--for telling Mr. Jamieson here about Mr. Innes' having been at his office the night he disappeared, and about my hearing them quarreling."

"What was it Warner overheard the woman say to Mr. Innes, in the library?" the detective asked me.

"She said `I knew there was something wrong from the start. A man isn't well one day and dead the next without some reason.'"

How perfectly it all seemed to fit!