The hardest part of their task was yet to be done, and that was to build a movable roof for their cabin.
Don, who had received explicit instructions from his father the night before, superintended this work, and by the middle of the afternoon the trap was completed and set, ready for the bear's reception.
It looked, as we have said, like a little log cabin with a flat roof.
One end of the roof rested on the rear wall of the trap, while the other was raised in the air, leaving an opening sufficiently large to admit of the entrance of any bear that was likely to come that way.
The roof was held in this position by a stout lever, which rested across the limb of a convenient tree.

A rope led from the other end of the lever, down through a hole in the roof, to the trigger, to which the bait--an ear of corn--was attached.

The bear was expected to crawl through the opening and seize the ear of corn; and in so doing, he would spring the trigger, release the lever and the roof would fall down and fasten him in the pen.

When all the finishing touches had been put on, the boys leaned on their axes and admired their work..