“I see.” Penfield drummed on the table for a moment with his left hand. “Could anyone have slipped past you and Colonel Thornton when you stood waiting in the hallway for the gas to evaporate?”
“No, we would have been sure to see them, and, besides, no one could have remained in that room alive, the escaping gas was overpowering.”
“Did the room have no other exit except the one door leading to the hall?”
“That is all I could discover. I searched the room thoroughly with Brett.” The detective nodded affirmatively. “We could find no trace of any other entrance or exit.”
“Strange!” exclaimed Penfield. “The windows are too great a height from the ground, and can only be reached by a scaling ladder.”
“And beside that,” put in Brett, “I’ve examined the ground under and near the two windows of that room, and there isn’t a trace of a footstep or ladder anywhere around.”
The coroner laid down his pen. “I think that is all just now, Mr. Hunter. Brett, will you ask Dr. Marsh to step here.”
The two men left the room. “I’ll wait in the drawing-room, Brett,” called Douglas, as the detective started upstairs to find the doctor. In a few minutes Brett reappeared in the library with Dr. Marsh.
“I won’t detain you long, doctor,” began Penfield. “Be seated. You were the first to examine the dead woman upstairs; what do you think caused her death?”