One of the chief points of difference in a Japanese house, as compared with ours, lies in the treatment of partitions and outside walls. In our houses these are solid and permanent, and, when the frame is built, the partitions form part of the framework. In the Japanese house, on the contrary, there are two or more sides that have no permanent walls. Within, also, there are but few partitions which have similar stability; in their stead arc slight sliding-screens, which run in appropriate grooves in the floor and overhead. These grooves mark the limit of each room. The screens may be opened by sliding them back, or they may be entirely removed, thus throwing a number of rooms into one great apartment. In the same way the whole side of a house may be flung open to sunlight and air. For communication between the rooms, therefore, swinging-doors are not necessary. As a substitute for windows, the outside screens, or shōji, are covered with white paper, allowing the light to be diffused through the house.