the rug which covered the upper hall, while tiny tacks with flat brass heads flew in every direction.
"Thumbtacks," Odell vouchsafed. "When the person who executed this little maneuver replaced the carpet he didn't dare hammer, with you and Mr. Lorne in that room so near by; so he pressed the thumbtacks in as a temporary hold, and left a good margin of the extra carpet that had been turned under loose, too, so as to give extra room for the tread to turn over without pulling out the tacks."
He folded the runner back across his knees; and the attorney uttered a sharp exclamation, as instantly silenced. A good four inches of the riser or faceboard had been sawed away at the top where it had formerly supported the tread; and the tread itself was cut through from wainscoting and balustrade at either end.
"When Mr. Lorne put his weight upon the step it cracked across at the line where it is level with the hall-flooring, and its outer edge crashed down until it rested on the lowered top of the face," the detective explained. "It had much the same effect as if one stepped from the center to the uptilted end of a see-saw. Do you observe something else, Mr. Titheredge?"
"Can't say that I do," the other replied, regarding thoughtfully the scraps of sawdust which the turned-back carpet revealed. "Whoever the fellow was—"
He halted abruptly as Miss Meade appeared from her room down the hall and came quickly toward them. Light as her footfalls were, the keen ears of the detective caught them; and in an instant he had turned up the strip of carpet once more and thrust its end hastily beneath the edge of the rug.