Frank looked with some surprise at the woman who was looking through the slide of his door. He had expected to see Nathan Graves. She also regarded him with interest.

"I have brought you some supper," she said.

Frank reached out and drew in a small waiter, containing a cup of tea and a plate of toast.

"Thank you," he said. "Where is the man who brought me here?"

"He has gone out."

"Do you know why he keeps me here in confinement?"

"No," said the woman, hastily. "I know nothing. I see much, but I know nothing."

"Are many prisoners brought here as I have been?" asked our hero, in spite of the woman's refusal to speak.

"No."

"I can't understand what object they can have in detaining me. If I were rich, I might guess, but I am poor. I am compelled to work for my daily bread, and have been out of a place for two weeks."

"I don't understand," she said, in a low voice, rather to herself than to him. "But I cannot wait. I must not stand here. I will come up in fifteen minutes, and if you wish another cup of tea, or some toast, I will bring them."

His confinement did not affect his appetite, for he enjoyed his tea and toast; and when, as she had promised, the woman came up, he told her he would like another cup of tea, and some more toast.

"Will you answer one question?" asked our hero.

"I don't know," answered the woman in a flurried tone.

"You look like a good woman. Why do you stay in such a house as this?"

"I will tell you, though I should do better to be silent. But you won't betray me?"

"On no account."

"I was poor, starving, when I had an application to come here. The man who engaged me told me that it was to be a housekeeper, and I had no suspicion of the character of the house--that it was a den of--"

She stopped short, but Frank understood what she would have said.

"When I discovered the character of the house, I would have left but for two reasons. First, I had no other home; next, I had become acquainted with the secrets of the house, and they would have feared that I would reveal them. I should incur great risk. So I stayed."

Here there was a sound below. The woman started.

"Some one has come," she said. "I must go down I will come up as soon as I can with the rest of your supper."

"Thank you. You need not hurry."

Our hero was left to ponder over what he had heard. There was evidently a mystery connected with this lonely house a mystery which he very much desired to solve. But there was one chance. Through the aperture in the closet he might both see and hear something, provided any should meet there that evening.

The remainder of his supper was brought him by the same woman, but she was in haste, and he obtained no opportunity of exchanging another word with her.

Frank did not learn who it was that had arrived. Listening intently, he thought he heard some sounds in the next room. Opening the closet door, and applying his eye to the aperture, he saw two men seated in the room, one of whom was the man who had brought him there.

He applied his ear to the opening, and heard the following conversation:

"I hear you've brought a boy here, Nathan," said the other, who was a stout, low-browed man, with an evil look.

"Yes," said Graves, with a smile; "I am going to board him here a while."

"What's it all about? What are you going to gain by it?"

"I'll tell you all I know. I've known something of the family for a long time. John Wade employed me long ago. The old millionaire had a son who went abroad and died there. His cousin, John Wade, brought home his son--a mere baby--the old man's grandson, of course, and sole heir, or likely to be, to the old man's wealth, if he had lived. In that case, John Wade would have been left out in the cold, or put off with a small bequest."

"Yes. Did the boy live?"

"No; he died, very conveniently for John Wade, and thus removed the only obstacle from his path."

"Very convenient. Do you think there was any foul play?"

"There may have been."

"But I should think the old man would have suspected."

"He was away at the time. When he returned to the city, he heard from his nephew that the boy was dead. It was a great blow to him, of course. Now, I'll tell you what," said Graves, sinking his voice so that Frank found it difficult to hear, "I'll tell you what I've thought at times."

"I think the grandson may have been spirited off somewhere. Nothing more easy, you know. Murder is a risky operation, and John Wade is respectable, and wouldn't want to run the risk of a halter."

"You may be right. You don't connect this story of yours with the boy you've brought here, do you?"

"I do," answered Graves, emphatically. "I shouldn't be surprised if this was the very boy!"

"What makes you think so?"

"First, because there's some resemblance between the boy and the old man's son, as I remember him. Next, it would explain John Wade's anxiety to get rid of him. It's my belief that John Wade has recognized in this boy the baby he got rid of fourteen years ago, and is afraid his uncle will make the same discovery."

Frank left the crevice through which he had received so much information in a whirl of new and bewildering thoughts.

"Was it possible," he asked himself, "that he could be the grandson of Mr. Wharton, his kind benefactor?"