The Decoration.—A great variety of decorative effects may be obtained in concrete pottery and in other articles made of this material for out-door use. In pottery these decorations may take the form of raised figures or ornaments, of borders or designs cut in the surface, and of inlays in colour. Whatever the form of design, the necessary cutting for it is best made when the cement has become well set but not very hard—i. e., from 6 to 10 hours after the finishing coat is applied. A stout, sharp, pointed knife blade is all the tool that will be required. A narrow chisel, however, may be found desirable for deepening the cuts. The knife should be guided by means of a ruler, which should be flexible if used on curved surfaces; and the depth of the cut will depend somewhat upon the size of the piece. In work similar to that described in the problem just given, a depth of 3⁄16 or 1⁄4 of an inch is sufficient. This cutting, of course can be made after the cement has hardened, by the use of hammer and chisel; but it will be much more difficult.
A square form
The Colours.—Colour cement for inlaid designs is made by using the best quality of white Portland cement as a base, colouring it with dry mineral pigments which are sold by dealers under the name of lime or cement-proof colours. Among the pigments suitable for this purpose are red oxide of iron, which produces a red; oxide of cobalt, which gives a good blue; chromate of lead, which produces yellow; carbonate of copper, which gives a good dark green; and burnt umber, which yields a good brown. These come as dry powders and should be mixed with the dry cement and marble dust, making a mixture of uniform colour, before the water is applied. In order to determine the right colour it is well to experiment with a small quantity of the various ingredients until a satisfactory shade has been found. Then with this as a guide a sufficiently large quantity should be mixed, in the same proportions, to the consistency of a thick paste, and applied to the design, which has been previously cut in the surface to be decorated. To insure thorough adhesion of the paste to the concrete, the cutting should be well moistened with a wet brush. A number of suggestive designs are shown in the accompanying drawings.
Rustic Furniture.—The lighter out-door furniture can be easily made up in a great variety of designs. The form of rustic settles and chairs is determined largely by the material which is available. Very useful and ornamental effects are produced by using sticks cut from the tops or from branches of small trees. Birch saplings, easily found in the second growth of some wood lots, afford a good supply of material. It is not necessary that the sticks be straight; the natural crooks and notches are often very useful in bracing the framework. Chairs, settles, tables, standards for flower boxes, and other articles of furniture may be made out of this rough and unfinished material.
A garden screen
Lattice Work.—Trellises and garden screens have been made in an almost endless variety of forms. Among the most satisfactory is the plain lattice work in squares and rectangles. Its simplicity and evident durability are points in its favour. Experience proves also that vines and other plants needing support are readily adjusted to this form of trellis. The size of the stock required in making the right-angled lattice work depends upon the uses to be made of it. For a garden screen the uprights need to be of 2 × 2 inch stock and of any convenient length. End posts of 3 × 3 inch stock will be required, to give necessary stiffness; and, if the screen be a long one, intermediate posts of the same size should be placed at intervals of ten or twelve feet. The horizontal pieces may be strips of 7⁄8-inch stock, 2 inches wide, set their full thickness into the uprights. Spruce furring, which lumber dealers supply in 2-inch widths, is suitable for the small rails; but if chestnut be used for the uprights it is well to use the same wood for the rest of the construction. The top and bottom rails should be of heavier stock, not less than 2 by 3 inches. The best foundation is a line of concrete posts, firmly set into the ground at intervals of 6 feet, to which the bottom rail or the uprights are fastened by means of irons set into the cement when the posts are formed. Two coats of dull green paint will protect the wood and properly subordinate the lattice work to the trailing branches which it supports.