brother's ear: "They are listening. We have a hole."
"Then we'll have to stay here," said Tom loudly, catching his cue instantly.
"Yes, and it's a shame," added Sam in a equally loud voice. "I suppose the others have gone on?"
"Certainly," said Tom calmly. "I was a chump to remain behind—only I wanted to find you. I got hold of a letter by accident."
A moment later, they heard the guards walk away, and then Tom told the truth about the letter, and Sam and Dick led him to the hole in the wall.
"It is not quite big enough to use, yet," whispered the eldest Rover. "But we hope to have it big enough by to-morrow. It's slow work, when you have got to be on your guard all the while."
"I'd like to know what became of the detective," returned Tom.
"He must have run away as soon as he saw how affairs were shaping," put in Dick. "I hope he rounds up the whole gang."
"So do I, and Dan Baxter with them," answered Tom.
Overhead, they could hear a constant tramping of feet and murmur of voices. They tried
