The old man chuckled.
"You are useful, Pedro," he said. "But these are useful, too. He pointed to a row of buttons and lights above a table by the door. One by one he indicated them.
"Here," he chortled, "is the gas button. That was first. The second was this light — when Duncan rang from the study. Then this light showed that some one within the cellar had brought down the elevator. How did the man get in? Through a loosely fastened window?"
"Yes."
"Careless of you, Pedro. We must attend to that. But look. I pressed this button. Up came the elevator. This button — down came the steel curtain. Here I released the trap — perhaps the young man has fallen in it. We shall see later. Then" — the old man's face gleamed with fiendish malice — "the last button. The wall is closing. Slowly closing. Soon it will be ended. Listen!"
A faint, distant thumping could be heard from the depths of the house.
"The machete is useful, Pedro," observed the old man. "Quick work — no noise. We will drop that body through the trap, too."
He looked at the Mexican quizzically.
Pedro grinned.
"You look different than usual," said Isaac Coffran. "You must have had some trouble, Pedro. Your scar is a trifle redder than I have ever seen it before. You must have given way to excitement! I never knew you to do that before."