"What was done with that money?" asked the captain with an earnestness that was almost tragic.
"Oh! The greaser made such a disturbance that the jailer let him keep it. He's got it with him in the jail."
A great sigh burst from Captain Hardy's lips. "Telegraph your men instantly," he cried, "to get those dollars. That Mexican is no smuggler. He's a spy. He's the man who carries the messages across the border. The messages are on the dollars. And here's the key to the cipher!"
And he drew from his pocket and laid before the Chief a battered silver dollar and a curiously marked celluloid disc.
CHAPTER XVI
AN UNEXPECTED MESSAGE
"Was he surprised?" cried the four boys of the wireless patrol, as their captain entered the living-room after his trip to the secret service offices.
Captain Hardy chuckled. "I think he was," he said. "But for a time it was I who was surprised. The Chief knew from his own men all about yesterday's message. One of them picked it up. What's more, he has a lot of amateurs in different parts of the country listening in, just as you are doing, and they picked up yesterday's message at enough different points to indicate the line of the secret stations we are after. The messages are crossing the border somewhere near El Paso. But the Germans are getting them across in some way other than by wireless. They know we'd spot their outfit quick. The Chief thinks some one telephones the messages the last lap and that a messenger carries them into Mexico."
"And what about the dollar and the disc?" asked Roy. "What did the Chief think of them?"