Bart leaped toward the door and quickly threw it open. The lamplight again streamed out into the corridor. But the sounds had ceased, and the corridor was empty. Hodge stared down the corridor in stupid bewilderment.

"Of all the strange things!" he gasped.

"That is the strangest!" Merriwell added. "You heard it for yourself then!"

Bart walked out into the corridor, peered out of doors through the glass set in the side door, and opened the door leading into the deserted office. There was nothing to be seen. When he came back, his face was beaded with moisture.

"Merry, I wish you'd tell me the meaning of that!"

"I wish you would tell me, Bart! You thought I was dreaming, or fancied that I saw and heard something. You see now that you were mistaken."

"Unless I am dreaming myself!"

"You are perfectly wide-awake, Hodge, and so am I! There is a mystery here."

"Never knew anything like it," mopping his face. "Whew! It brings the cold sweat out on me!"

He dropped down into the chair by the window, leaving the corridor door open. Nothing further was heard.