Jack looked closely at the man who did not have the marks of a bad character anywhere, being well dressed, well spoken, and evidently a man of easy means and considerable culture.

There was something about him, nevertheless, that made Jack think he was not what he seemed, and he tried to think what it was and to place him in his mind.

“Will you describe the watch, please?”

“Certainly, with the greatest of pleasure,” and the man proceeded to give an accurate description of the watch, not omitting the slightest detail, giving the name of the maker, the size, the number of diamonds on the case, and, in fact, everything about it.

“Number, please?” said Jack, still looking fixedly at the man.  “You will know the number of the watch, of course?  Persons who own valuable watches always make a record of the number.”

“The number?” said the other.  “Oh, yes, to be sure.  I have it in my pocket-book.  The rest of the description is accurate, is it?”

“Let me hear the number,” said Jack quietly.  “Two watches may be exactly alike, but have different numbers.  I have not said that your description is correct.  You have the number?”

“Why, of course!” said the other somewhat impatiently, and all at once a light broke in upon Jack.

The man was the one he had heard, but had not seen, talking with the foreign nurse maid on the bank of the kill earlier in the afternoon.

He had tried to place the man’s voice, but while he talked in low, pleasant tones, with a good inflection, he was puzzled, knowing and yet not knowing it.

The instant that the man spoke in impatient, angry tones, such as he had used on the bank of the kill, Jack recognized him, and he wondered that he had not done so before.

The man took a slip of paper from his pocketbook, and read out a number written in pencil, the exact number of the watch which Jack had found.

“Is that correct?” he asked Jack with a certain tone of triumph.

“Perfectly so,” the boy answered.

“And the description is correct also?”

“Absolutely.”

“Ah, I am glad of that.  I mentioned a reward a few minutes ago, and I am perfectly willing to pay it.  Will a hundred dollars be sufficient?”

“It would be more than ample in the event of my having the actual owner of the watch to deal with,” in a quiet tone.

The man flushed, glared angrily at the boy, and cried excitedly: 

“What do you mean by that, you young scoundrel?  Do you dare to say that I am not—–­” and then he stopped short, laughed, and said in his former pleasant tones:  “but this is a joke, of course.”

“No, it is not, it is the truth,” said the boy.  “Dr. Wise, don’t give it to him.  He is not the real owner of the watch.  Have you forgotten your conversation with Gabrielle this afternoon?” to the man himself.  “Well, I have not, nor has my friend, and we both heard it.  It was on the banks of a little kill that runs into the Hudson a few miles from here, and about a mile up from the river.”