"Put your collar on, and make it snappy," laughed Ned. "We've got some work ahead of us this morning!"
After breakfast they hurried back to No. 16, barred the door against intruders, especially Kewpie, sat down at opposite sides of the study table, and faced the problem. They continued to face it until nearly eleven. They examined the window-sill for clues, and found none. They leaned out and studied the ivy by means of which the mysterious visitor had reached the second story, and it told them nothing, or so it seemed at the moment. As they turned back to the room Ned said idly: "It's lucky the fellow didn't have to get to the third floor, for I don't believe he could have made it. That ivy sort of peters out above our window."
Laurie nodded uninterestedly and silence ensued, just as silence had ensued so frequently before in the course of morning. Then, several minutes later, Ned said suddenly, questioningly:
"Thurston!"
Laurie shook his head. "Not likely. Besides, what reason—"
"Wait a minute. I didn't tell you. It didn't
