There were many things to be explained, and the sailors were the only ones who would be apt to tell the truth.
Presently a noise like that made by dragging a heavy body over the floor came from the private room just over Nick’s head.
The paid assassin of the diamond merchant was about to complete his task.
Just at this moment the workmen employed at the front of the basement extinguished their light and went away. Their departure gave Nick an opportunity to work out a plan which had been forming in his brain.
The sailor was undoubtedly badly wounded now, and would, of course, be still further hurt by a long drop into the sub-basement.
Nick wanted to get at the man while he was in good shape—while he could talk of the events of the previous night.
A long board lay on one of the packing boxes, and the detective took this and carried it to the shaft.
“I’ll switch the victim off their trunk line to death or insanity,” thought Nick, “if my usual luck will hold for a few minutes.”
The board was wide as well as long, and perfectly smooth on one side. Bracing one end against the wall of the shaft opposite the door, the detective placed the other against a heavy box, which he dragged up to the dark doorway.
“Now, my cunning friends,” he mused, “your sailor will strike this slanting board when you dump him into the shaft and be shunted into this basement. I hope they will dump him in without throwing a flash of light into the shaft. That might spoil everything, as it would disclose the presence of the board and might make it necessary for me to do a little shooting.”