He was about to explain more of the characteristics of the bully and his cronies when a fresh interruption occurred.  This time it was Hiram Nelson.  He was almost as abashed as Merritt had been when he found that his excitement had carried him into what seemed a family conference.

“It’s all right, Hiram.  Come right in,” said Mr. Blake cheerfully.  “Come on out with your news, for I can see you can hardly keep it to yourself.”

“It’s going round the town like wildfire!” responded the panting boy.  The others nodded.  “I see you know it already,” he went on.  “Well, I think I’ve got a clue.”

“You have!  Come on, let’s hear it quick,” cried Rob.

“Well, I was up late with Paul Perkins last night, talking over the aeroplane model competition, and didn’t start home till about midnight.  As I was approaching the armory I thought I saw a light in one of the windows.  I couldn’t be certain, however, and I put it down to a trick that my eyes had played me.”

“Well, that’s all right as far as it goes,” burst out Rob.  “It probably was a light.  I wish you’d investigated.”

“Wait a minute, Rob,” said his father, noting Hiram’s anxious face.  “There’s more to come, isn’t there, Hiram?”

“You bet!  The most exciting part of it—­the most important, I mean,” went on young Hiram, with an important air.

“Oh, well, get down to it,” urged the impatient Rob.  “What was it?”

“Why, right after I’d seen the light,” went on Hiram, “I thought I saw a dark figure slip around the corner into that dark street.”

“A dark figure!  Hum!  Sounds like one of those old yellow—­back novels,” remarked Mr. Blake, with a smile.

“But this was a figure I recognized, sir,” exclaimed Hiram.  “It was Bill Bender!”

“Jack Curtiss’ chum!  They’re as thick as two thieves,” burst out Merritt.

“And I believe they are two thieves,” solemnly put in Rob.

“Well,” went on Hiram, “the next minute Bill Bender came walking round the corner as fast as if he were coming from somewhere in a great hurry, and was hastening home.  He told me he had been to a birthday party at his aunt’s.”

“At his aunt’s,” echoed Mr. Blake.  “Well, that’s an important point, for I happen to know that his aunt, Mrs. Graves, is out of town.  She visited the bank yesterday morning and drew some money for her traveling expenses.  She informed me that she expected to be gone a week or more.”

“I knew it, I knew it!” shouted Rob.  “That fellow ought to be in jail.  He’ll land there yet.”

“Softly, softly, my boy,” said Mr. Blake.  “This is a grave affair, and we cannot jump at conclusions.”

“I’d jump him,” declared Rob, “if I only knew for certain that he was the thief!”

“I will inform the police myself and have an investigation made,” Mr. Blake promised.  “We will leave no stone unturned to find out who has been guilty of such an outrage.”