We had two doors; one at the back of the house, from which a ladder extended down to the ground, and another opening out onto the veranda, from which we dropped a ladder down to the Goblins' Dancing Platform. In order to save space we used sliding instead of swinging doors. The back door frame was 5-1/2 feet high and the front door frame 6 feet high. The doors were mounted on the outside of the building. The side posts of each frame were 2-1/2 feet apart, and the lintel and sill extended 3 feet beyond the side post at one side. The upper face of the lintel was planed down perfectly smooth, and its edges were tapered off to make a track for the

Fig. 144. Section of the Door and Frame.

rollers on the door. The rollers consisted of two spools, which turned on tenpenny nails driven into the top of the door. At the lower end two more spools were mounted, turning on nails driven in the bottom edge of the door. The rims of the spools extended slightly beyond the outer face of the door and rolled against the sill. To keep the water from leaking in at the top a slanting board was fastened above it, as shown in Fig. 144. The back door was similarly constructed. Our tree house was completed by a running balustrade around the veranda.

A Filipino Bamboo Tree House.

It strangely happened that just after our tree house had been built we received a photograph from Uncle Ed of a Filipino tree house made of bamboo.