“I think I would, Jack. I’d think right away what that person was doing upstairs.” Ned scratched his head. “No, if I did meet somebody, I’m sure it must have been one of the cadets. But who it was, I can’t think.”

A little later Colonel Colby continued his investigation by asking all those who had been inside the building during the celebration to come forward and tell anything they could that might be of advantage. It developed that not only Ned but also Ralph Mason, Bart White and two of the older cadets named Lawrence and Philips had been upstairs some time between eight and eleven o’clock. The most of these cadets said they had seen no one else upstairs in the building. But Bart White declared while at one end of a long corridor he had seen some one slip around a corner out of sight. He was not sure whether the person had been a cadet, one of the hired help, or an outsider.

“It was either a man or a big boy,” said Bart. “But he moved so quickly and it was so dark I didn’t recognize him, even if I happened to know him.”

“And what time was this?” questioned Colonel Colby.

“Some time between half-past nine and ten o’clock.”

Bart was asked to show the colonel where the disappearance of the stranger had taken place, and it was proved that this was at a point just around a corner from the room where the footprints leading to the fire-escape had been discovered.

“Perhaps you saw the person just at the time he was making his escape,” was Colonel Colby’s comment. “We will look for footprints below the fire-escape.”

This was done, but the cadets the night before had tramped around the school building so much that the footprints were hopelessly mixed. Then the boys were questioned as to whether or not they had seen any one dropping from the fire-escape to the ground, and all answered in the negative.

“We will question the hired help and see what they have to say,” announced the master of the school.