ing, that boy must have followed the two men when they left."
"He couldn't do that without our seeing him," said Sam.
"And why not? Here's a back door, remember—and it's pretty dark outside."
"That may be so," returned Tom, shaking his curly head in perplexity. "It's too bad we didn't follow Girk and Baxter up—at least as far as the street."
"Perhaps Dick is at our house waiting for us to come back," put in Frank. "Let us go home and see. We can come back early in the morning." He looked at his watch. "Do you know that it is after two o'clock? I'm afraid my father will worry about me."
They talked the matter over and decided to return to Frank's home without further delay.
It was a silent trio that walked the streets, which were now practically deserted. Tom and Sam were much worried and Frank hardly less so, for the senator's son and Dick had been warm friends for years.
When they reached the mansion they found Senator Harrington pacing the library nervously.
"Well, here you are at last!" he cried. "I was wondering what had become of you."
He listened to their tale with close attention.
