The four walls of a room inclose a space to dwell in, in comfort and security. The windows show us outward real life and nature. The walls should not compete with the windows. Nature must be translated into the terms of line and form and colour, and invention and fancy may be pleasantly suggestive in the harmonious metre and rhythm of pattern.
A wall surface extends horizontally and vertically, but the vertical extension seems to assert itself most to the eye.
Any arrangement of lines of the trellis or diaper order logically covers a wall surface, and may be appropriately used as a basis for a wall pattern, whether merely to mark the positions of a simple spray or formal sprig pattern, or as a ground-plan for a completely filled field of repeating ornament, whether painted, stencilled, or in the form of wall-paper or textile hanging.
In the simple geometric net of squares or diamonds or circles, however, there is nothing that emphatically marks adaptability to a vertical position. Such plans in themselves are equally appropriate to the floor in the form of paving and parquet. The ogee plan, however, and its variant, the vertical serpentine or spiral plan, at once suggest vertical extension, the former perhaps by its leaf-like points arranging themselves scale-wise, and the latter by its suggestion of ascending movement.
It is noteworthy that in the course of the historic evolution of mural decoration, designs based upon these systems constantly recur. They are part of the pattern-designer's vocabulary of line, and among the principal, though simplest, terms by which he is able to express vertical extension.
The question of scale in designing mural decoration of any sort is very important. This demands a certain power of realizing the effect of certain lines and masses if carried out, and the relation of one part to another as well as to the dimensions of the walls and the room itself. Here, as indeed throughout art, a reference to the human figure will give us our key, since after all decoration goes to form a background for humanity. With natural flowers and leaves it is always right to design for mural purposes on the same scale as nature.
Scale