“If you gentlemen will allow me,” said Chester, “I shall make a suggestion that may save us all time and bother.”

“Well?” demanded one of the men.

“If you’ll give me the gun you deprived me of,” said the boy, “I’ll give my word to hold our friend here safe until the ambassador is brought back to consciousness.  Also, I give my word not to attempt to escape.”

The others eyed him closely for a brief moment.

“All right,” said the man who had gone after the ambassador.  “Here.”  He passed over his automatic.

Chester took it and covered Robard.

“You can release him now,” he said to the big Austrian’s captor.  “He’ll make no break while I have him covered.  He knows me too well by this time, don’t you, Robard?”

The latter’s reply was a low growl.

The other Austrian released his hold, and stood back.  For an instant it seemed that Robard would spring forward and give battle to all three, but as Chester’s revolver covered him steadily, he changed his mind and stood still.

Immediately the others began the work of reviving the ambassador, and five minutes later their efforts were rewarded.  The ambassador moaned feebly, and a few seconds later sat up.  His eyes fell on Robard, and he jumped quickly to his feet.

“So!” he exclaimed.  “Guard him carefully, boy.  He’s a dangerous man.”

“I’ll guard him,” replied Chester briefly.

Suddenly the Austrian smote himself on the breast.

“The plot!” he cried.  “Robard’s plot!”

“Has failed,” interrupted Chester.  Then noticing the look of surprise on the ambassador’s face, he explained.

“We overheard the conversation in the room where we were locked, sir.  My friends managed to escape and give the warning.  The plot has failed.  Robard told me as much.”

“I’m glad,” said the ambassador simply.  “And now, what am I to do with you?”

“Let me go, sir,” was the lad’s reply.

The ambassador considered the matter.

“I’ll tell you,” he said at length, “I would like for you to go to Vienna with me and substantiate my story to the emperor.  You will say that my story should need no proof, as I am the ambassador, but Robard has influential friends there.  He would easily discredit the stories of these two men here.  With you it would be different.  Will you go?”

“I would rather not, sir,” replied Chester quietly.

“I must insist,” urged the ambassador.

For some reason that Chester was never afterwards able to explain to himself, he suddenly grew terribly angry.

“No, I won’t go!” he shouted, and waved a fist in the very face of the ambassador.

The latter looked at him in amazement; then took his decision.

“You shall go anyhow,” he said softly.  “Seize him, men!”

CHAPTER XV.