From among the articles in front of him the general selected a solitary 44-caliber revolver cartridge and, holding it up, said: 

“What do you say to this?”

“I don’t know what to say.  Where did it come from?”

“It was found in the cloth pocket of your valise.”

O’Reilly frowned; then a light of understanding irradiated his frank countenance.  “It must have lain there ever since I left Matanzas, three months ago.”

“Ha!  Matanzas!” fiercely ejaculated a colonel.  “What were you doing in Matanzas?”

It was unnecessary to prevaricate now.  Johnnie told of his earlier connection with the Carter Importing Company, gave names, dates, and facts to bear out his statements, and challenged his accusers to verify them.

Undoubtedly some of his hearers were impressed, but they were by no means convinced of the innocence of his present purpose, and, in fact, the ferocious colonel seemed to regard past residence in Cuba as proof conclusive of a present connection with the rebels.  Johnnie gathered that he was suspected of being one of those American engineers who were reported to have been engaged to instruct the enemy in the use of explosives:  his inquisitors did their best to wring such an admission from him or to entrap him into the use of some technical phrase, some slip of the tongue which would verify their suspicions.  They even examined his hands with minutest care, as if to find some telltale callous or chemical discoloration which would convict him.  Then finally, to give him the lie absolute, the aggressive colonel seized a nickel-plated atomizer from the table and brandished it triumphantly before the young men’s eyes.

“Enough of this pretense!” he cried.  “What is this instrument, eh?”

“It is evidently an atomizer, a nasal syringe.  I never saw it before.”

“It’s mine,” said Leslie Branch; but the colonel did not heed the interruption.

“Ha!  And pray explain its use.”

Johnnie undertook to do so, but it was plain that his words carried no conviction, for his mocking inquisitor gave a loud snort and gestured eloquently to his commander.  “There you have it!” he declared, proudly.  “This impostor betrays himself.”

The other officers were eying the unfamiliar article curiously; one of them ventured gingerly to handle it; they exchanged whispers.

“What do you call it?” the general inquired, leaning forward.

This was the colonel’s moment.  “I will tell you!” he said, with a sneer at O’Reilly.  “I am something of a genius at mechanical inventions, and therefore I am not for a moment deceived by this fellow’s common lies.  This”—­he paused dramatically and held his brother officers with a burning glance—­“this instrument, in my opinion, was devised for the purpose of injecting fulminate of mercury into dynamite.”

There was a breathless hush.  The Spaniards stared at the little syringe with amazement.