“There is a small transom over that door opening onto the hall, it is true, but it is not large enough for a child to crawl through, much less a man. Dr. Sprague seemed to think that Berjet was asphyxiated. Yet this room, as you yourself observed when we entered it, sergeant, contained not the slightest trace of any kind of gas. As a matter of fact, the room is lighted by electricity. What are we to conclude from these premises? That the poison fumes, assuming that poison fumes were the cause of Berjet’s death, were administered by human hands? If so, oblige me, my friend, by telling me how the owner of those hands got out of the room?”
“Well, if the murderers were invisible, and they were, if the testimony of you and Deweese counts for anything,” rejoined Strange, “they might have followed Berjet through the window without having been observed by you.”
“Invisible murderers!” snorted Peret, with a contemptuous shrug of his shoulders. “You are growing feeble-minded, my friend. Didn’t Berjet say he saw his murderers?”
“So you say,” returned Strange rudely. “But you didn’t see Sprague’s murderer, although you claim to have been looking at him when he was attacked. Maybe your eyesight is failing you,” he added.
Peret glared at the detective sergeant, but said nothing.
“Perhaps Berjet was subject to a hallucination,” ventured Strange, after a moment’s thought. “He may just have imagined he saw the murderers.”
“Perhaps he just imagined he was murdered, too,” retorted the Frenchman, and returned to his examination of the room.
At this juncture someone rapped on the door opening into the hall. Strange crossed the room, turned the key in the lock and, opening the door, admitted Central Bureau Detectives Frank and O’Shane.
“Well?” demanded Strange.
“Major Dobson sent us four men from headquarters, and we’ve searched the house as you ordered,” answered O’Shane. “We drew an absolute blank. The house is empty.”