Penny Nichols Finds a Clue

In former years it had been occupied by a chauffeur whom Mr. Nichols employed, but now that the detective drove his own car it was used only for the storage of a few old boxes and trunks.

"Don't you dare go up there!" Susan whispered tensely, sensing the thought in her chum's mind. "It isn't safe."

"It's safe enough if you stand guard here at the door," Penny insisted. "If anything goes wrong scream for Mrs. Gallup."

Before Susan could stop her she tiptoed across the cement …