of diamonds rings to select from. She professed to be on her way
from Brooklyn and to be in haste. She is, she says, staying at the house
of a friend at No. 282 West Forty-Seventh between Seventh and Eighth
Avenues. She is to go away to-morrow and would like to make choice of a
ring to-day."

Mark was rather surprised to hear this full account from the jeweler. As
he was only to take the part of an errand boy he didn't see the
necessity for it. He was soon enlightened.

"Now," proceeded the jeweler, "I am of the opinion that this lady is a
clever swindler. I believe she wants to get hold of the rings, and carry
them off without paying for them."

"Then you won't send them to her, I suppose."

"I would not if I were absolutely sure that she is a fraud, but this I
don't know. She may be a _bona fide_ customer, and if so I should like
to sell her a ring."

"How can you find out, sir?"

"I hope to do so with your help."

CHAPTER XI.

MR. HAMILTON SCHUYLER IS ASTONISHED.

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 qu