"There is a button set in the wall where I stand," suddenly said the unseen Merle; "I press it, and a match is ignited which lights the lamp. I will touch it, and we fire at first sight of each other. Does that suit you, Mr. Broadbrim?"
"It suits me," said the detective.
As he spoke he moved toward that part of the room from whence the voice had come and stopped.
The minutest space of time seemed an hour, but all at once the whole room seemed on fire, for Merle Macray had pressed the secret button in the wall.
The next instant the figure of the detective cleared the carpet before him, and his hand closed on the arm which came up with a cocked revolver at the end of it.
Merle recoiled, but the grip of the trailer was not to be broken.
The men stood face to face and looked into each other's eyes.
"It was unfair!" hissed the hunted man.
"With me, when there is a murderer to catch, everything is fair," was the answer.