The internal architecture of the tree had now to be attended to, and early the following morning we prepared for the laborious task. A door had first to be made, so at the base of the trunk we cut away the bark and formed an opening just the size of the door we had brought from the captain's cabin, and which, hinges and all, was ready to be hung. The clearing of the rotten wood from the center of the trunk occupied us some time, but at length we had the satisfaction of seeing it entirely accomplished, and, as we stood below, we could look up the trunk, which was like a great smooth funnel, and see the sky above. It was now ready for the staircase, and first we erected in the center a stout sapling to form an axis round which to build the spiral stairs; in this we cut notches to receive the steps, and corresponding notches in the tree itself to support the outer ends. The steps themselves we formed carefully and neatly of planks from the wreck, and clenched them firmly in their places with stout nails. Upward and upward we built, cutting windows in the trunk as we required, to admit light and air, until we were flush with the top of the center pole. On this pole we erected another to reach the top of the tree, and securing it firmly, built in the same way round it until we at length reached the level of the floor of the nest above. To make the ascent of the stairs perfectly easy we ran a hand-rail on either side, one round the center pillar, and the other following the curve of the trunk.