The jeweler took from his case two diamond rings. They were large, brilliant, and showy.

"How do you like the appearance of these rings?" he asked.

"They are beautiful!" exclaimed Mark admiringly.

"Don't you think the lady would admire them?"

"I should think so, sir."

"What should you think they are worth?"

"A hundred dollars apiece," guessed Mark.

"If the diamonds were genuine, one would be worth three hundred and fifty dollars and the other four hundred."

"Are they not genuine?" asked Mark in surprise.

"Paste, my boy, paste. The gold, however, is real. Instead of being worth the sum mentioned, one is worth perhaps three dollars and a half, the other four dollars."

"But I shouldn't think it would be worth your while to keep false diamond rings."

"Nor would it if all persons were honest. I never sell them. I only sell genuine jewelry. I will let you understand the use I mean to make of them. These two rings I mean to have you carry to Mrs. Montgomery on Forty-Seventh Street."

"But suppose she takes them for genuine?"

"Then I will make them so. In other words, I will take out the paste diamonds and replace them with real stones. If on the other hand any fraud is intended it won't benefit her much."

"Very well, sir. I think I understand."

"You must to a certain extent exercise your own discretion. I judged from the observations I made the other afternoon that you are a boy who possesses that important quality."

"Thank you for the compliment."

"I will tell you what made me suspect the woman of whom I have spoken. First, the name. She calls herself Mrs. Philip Montgomery. It sounds like a fictitious name. Again, she is a stout, rather common-looking woman, with a florid complexion and larger features. Now Montgomery is an aristocratic name. Again, she says she is from Buffalo. Swindlers generally hail from some distant city. Then again, it is rather suspicious that she should be in such haste.

"The purchase is an important one, and the amount to be paid—she herself fixed the approximate value—is considerable. You would think she would wish to inspect my stock carefully before making a selection. Instead of this she only asked to have two rings sent up to her of the value of three or four hundred dollars, and she would make choice of one of them."

"It does look rather suspicious, sir."

Mr. Swan gave Mark some further directions, and the latter started up town on the Eighth Avenue horse cars, which he took on the lower side of the Astor House.

"This is new business to me," thought Mark. "I feel an interest to see this Mrs. Montgomery. If she is planning to entrap me, she won't make as much as she anticipates."

Mark had the rings, each in a little morocco case, carefully laid away in the inside pocket of his coat.

When they reached Canal Street, to Mark's surprise, his cousin Edgar entered the car. He did not recognize Mark at first, the latter no longer wearing the messenger's uniform.

"How do you do, Cousin Edgar?" said Mark.

Edgar turned sharply around.

"Oh, it's you, is it?" he said. "Please don't call me cousin."

"I am just as much ashamed of the relationship as you are," responded Mark with a comical smile.

"That is impertinent. Besides it isn't true. Have you been discharged from the telegraph service?"

"No; what makes you think so?"

"Because you are not wearing the uniform."

"I am working for a party that doesn't want me to wear it while in his service."

"Who is it?"

"I don't feel at liberty to tell."

"Oh, just as you like. Isn't that a new suit?"

"Yes."

"Where did you get it?"

"I bought it."

"Business seems to be pretty good with you. How much did it cost?"

"Eighteen dollars."

"Is it paid for?"

"Of course it is."

"I didn't know but you might have bought it in installments."

"I don't have to do that."

"Yet you pretended a little while since that you and your mother had hard work to get along."

"Business is looking up."

Edgar got out at Twenty-Third Street. Mark kept on till he reached Forty-Seventh Street. He walked toward Seventh Avenue, and finally stood in front of the house in which the customer for the diamond rings was staying. It was a plain three-story residence with nothing peculiar about it. Mark rang the bell, little suspecting what was in store for him.

A boy of about seventeen, shabbily dressed, answered the bell.

"Is Mrs. Montgomery at home?" asked Mark, referring to a card.

"I guess so," answered the boy.

"I should like to see her."

"All right! I'll go up and ask."

The boy left Mark standing in the doorway, and went up-stairs.

He returned in a very short time.

"You're to come up," he said.

Mark followed him up the staircase and into a back room. It was scantily furnished. There was a lounge on one side of the room, and a cabinet bed on the other. These, with three chairs and a bureau, constituted the furniture.

"Just step in here," said the boy, "and I'll call Mrs. Montgomery."

Mark took a seat on the sofa and awaited the arrival of the lady.

He did not have long to wait. The door opened, but the lady he expected did not appear. Instead, a young man entered whom Mark instantly recognized as the person who had left the Fifth Avenue stage under suspicious circumstances on the day when the old lady was robbed of her pocketbook.

Mark started and wondered if the recognition was mutual. It did not appear to be.

"You're the jeweler's boy, I believe?" said the newcomer languidly.

"I came from Henry Swan."

"Exactly, and you have brought two diamond rings with you?"

"Yes."

"All right! You can show them to me."

Mark's suspicions were aroused and he felt that he had need of all his shrewdness. He was very glad now that the diamonds were paste and the rings of little value.

"Excuse me," he said, "but I was told to deliver the rings to Mrs. Philip Montgomery."

"Yes, that's all right. Mrs. Montgomery is my aunt."

"I should like to see her," persisted Mark.

"Come, boy, you're too fresh. It'll be all the same if you hand the rings to me."

"I don't think so. Isn't Mrs. Montgomery at home?"

"Yes, but she has a severe headache and cannot see you at present."

"Then perhaps I had better call again."

"No you don't. I am a gentleman and won't permit you to insult me."

"What do you want to do?"

"To take the rings up to my aunt. If she likes them, or either of them, she will send you down a check."

Mark reflected a moment. Remembering that the rings were not valuable, he decided to show them.

"Here are the rings!" he said, producing them from his pocket.

The young man opened the small caskets, and his eyes lighted up with satisfaction when he saw the glittering rings.

"What is the price?" he asked, looking up.

"That ring is three hundred and fifty dollars, the other is four hundred."

"Seven hundred and fifty together."

"Yes."

"I will show them to my aunt. Perhaps she may decide to keep both."

"You won't be long?" asked Mark, as the young man left the room.

"No. I'll be back as soon as my aunt decides."

Left alone Mark began to think over the situation. His recognition of his unprincipled acquaintance of the Fifth Avenue stage convinced him that some fraudulent scheme was being carried out. Mrs. Montgomery was probably a confederate of the young man who had just left the room.

"Is he going up-stairs or down?" thought Mark.

He listened, and thought he heard the front door open and shut. It occurred to him to open the door of the chamber and look down-stairs.

He started to do this, but to his surprise found that the door was fastened in some way. He had not heard a key turned in the lock. Possibly there was an outside bolt.

"What object can they have in keeping me a prisoner?" he asked.

Should he ring the bell and summon a servant? If he did so, he would have to leave the house in a state of uncertainty. No! he decided to wait and let further events throw a light on the mystery.

Meanwhile the young man who had possessed himself of the rings left the house, for it was he who had descended the stairs and gone out into the street. He bent his steps to the nearest pawnshop on Eighth Avenue, and taking out one of the boxes, said in a nonchalant voice:

"What will you loan me on this magnificent diamond ring?"

The pawnbroker took the box, and drawing out the ring held it up in the best light. He examined it through a magnifying glass, and a gleam of intelligence flashed in his face.

He returned to the counter, and scrutinizing the young man who had presented it asked in a matter-of-fact tone, "What do you want to borrow on the ring, my friend?"

"Two hundred dollars," answered the customer promptly.

"Humph!" said the pawnbroker with an amused smile, "two hundred dollars is a large sum of money."

"Yes, but the ring cost three hundred and fifty dollars. I am asking a little more than half price."

"So! the ring cost three hundred and fifty dollars! Did you pay that price for it?"

"No, the ring does not belong to me."

"Then to whom does it belong?"

"To my aunt, Mrs. Philip Montgomery."

"I do not know the lady. Does she live in the city?"

"No, she lives in Buffalo."

"And she sent the ring to you?"

"Yes, she sent it to me. She is in want of a little money, and did not like to ask her husband for it, for he might not be pleased. So she wants to borrow money on this ring which was given her by her brother at the time of her marriage."

"So, so! And your aunt would like me to lend her two hundred dollars on the ring?"

"Yes, sir."

"I think you will have to carry it to some other pawnbroker, my friend!"

"I don't mind taking a little less," said the young man, who was anxious for more than one reason to realize on the ring at once.

"How much now do you call a little less?"

"Well, say a hundred and seventy-five dollars. Probably my aunt will be able to redeem it in a few weeks."

"If I give you a hundred and seventy-five dollars," laughed the pawnbroker, "I think your aunt will let me keep it for good."

"As to that," said the young man impatiently, "I can make no promises. How much will you give on it?"

"I might give you a dollar and a half," answered the pawnbroker composedly.

"A dollar and a half!" exclaimed the young man, clutching at the counter for support. "A dollar and a half on this magnificent diamond ring, for which my aunt paid three hundred and fifty dollars! What do you mean?"

"I mean not to be cheated, my friend. How much do you think this magnificent ring is worth?"

"I have told you what it cost."

"My friend, you are very much mistaken. The ring cost only three dollars or three and a half."

"What do you mean?" gasped the visitor, turning pale.

"I mean that it is not diamond, but paste."

"But—it came from a jeweler of great reputation. Surely you have heard of Mr. Henry Swan."

"Yes, I have heard of Mr. Swan. If you will bring him here, and he will say that the diamond is real, I will see if I can't give you more."

"Wait!" said the customer hurriedly, drawing out the other casket. "Look at this ring, and tell me what it is worth."

The pawnbroker took it to the window and examined it attentively.

"That may be worth four dollars," he answered, after a brief pause.

"And is this stone false also?"

"Yes, my friend."

"Then I won't pawn either. Here, give me back both rings."

"Here they are."

"I am afraid you are not a good judge of diamonds. I am sure they are real."

"Go somewhere else, my friend, and satisfy yourself. If you can find any one in my line who will give you five dollars for either, you had better take it and call yourself a fortunate man. Will you leave your name?"

"My name is Hamilton Schuyler, and I live on Second Avenue."

"It is a very good name, my friend. I think you must belong to the Four Hundred."

"I do," answered Schuyler haughtily.

"It is a pity you should have to pawn your aunt's diamonds, and such diamonds!" chuckled the pawnbroker.

But Mr. Schuyler had already left the shop, and was hurrying along the avenue to another of the same class at which he had occasionally had dealings.