They did so, and presented themselves at Ezra Cohen’s establishment soon after the store was opened for business that morning.

The merchant was already there, awaiting them, and received the two gentlemen in his private office, where they held a confidential conversation regarding the matter in hand.

The expert was quite confident, after listening to Mr. Cohen’s description of the diamonds, that they would prove to be the ones they were seeking, but the detective was not quite so hopeful; he had been disappointed so many times of late that he looked upon the dark side, while he was somewhat skeptical about the supposed miner making his appearance again.

About nine o’clock, however, the man swaggered into the store, an enormous quid of tobacco inside his cheek.

“He has never been in Australia,” said Detective Rider, in a low tone, but with sudden energy, as he and his companion watched him approach the counter, where Mr. Cohen was quietly examining a case of watches.

“Wall,” he remarked, in his broad, drawling tone, “got yer expert on hand this mornin’?  I’d like to close up this ’ere business before I go up to Brownsville.”

“Yes, I think I can settle about the diamonds to-day,” Mr. Cohen politely remarked.  “James,” to a clerk, “please ask Mr. Knowlton to step this way.”

James disappeared, and presently an elderly gentleman in spectacles issued from the private office.

“Mr. Knowlton,” said the merchant, “this is the man who wished to dispose of some diamonds.  Will you examine them, and give your opinion of their value?”

The miner darted a quick, searching look at the new-comer; but apparently the man was intent only upon the business in hand.

Drawing forth his leather pouch, the miner untied it and emptied its contents upon the square of black velvet which had been laid upon the show-case to receive them.

Mr. Knowlton examined each stone with careful scrutiny through a powerful glass, never once speaking until he had looked the collection through.

“They are quite valuable,” he remarked, as he laid the last one down.  “These,” indicating the two large ones, “are especially so; you have been very fortunate, sir, to make such a collection, for there is not one poor one in the lot.”

The miner gave a slight start at this observation, and the color deepened on his face; but he replied, with his habitual frankness: 

“Well, I’ve had poor ones—­plenty on ’em; but these were saved for a special purpose,” and he winked knowingly at Mr. Cohen.  Then he added, as he shot a sweeping look around the store and out through the window upon the sidewalk:  “Jest give us their value in round figgers, and well soon settle this matter.”

The expert quietly made a memorandum upon a card and laid it before the jeweler, then immediately withdrew to the private office.

“Well?” demanded Tom Rider, his keen little eyes gleaming with repressed excitement, as Mr. Knowlton shut the door after him.