Wall

Wall \- COVERINGS. The present article deals with this subject (see Mural Decoration for art and archaeology) from the practical point of view in connexion with house-furnishing. In selecting a wall-covering, the chief factors to be borne in mind are the conditions of the room, viz. the use to which it is to be put, and its lighting, aspect and outlook.

Marble is one of the most beautiful materials that can be chosen for covering a wall. The variety of its natural markings and colour gives a wide choice that enables it to be employed in practically any scheme of colouring and for rooms of any aspect and of any description. The working up of the marble is done w a r  mostly by machinery; the saws used are flat strips of steel ?inivg set in the frame of a machine and worked to and fro, sand and water being constantly supplied to assist in the work of cutting. Mouldings are worked to the desired profile by rapidly revolving carborundum wheels, and are afterwards polished by hand. Marble wall-slabbing needs very careful fixing, and should be well supported by a sufficient number of cramps at a little distance from the wall, leaving a space of about half an inch at the back of the slab. Nonrusting cramps should be used, such as those made of copper or bronze. A cement made of plaster of Paris and marble dust mixed in the proportion of two parts to one should be used for fixing, as pure plaster, especially if new, is liable to swell and cause the marble to crack. Marezzo and Scagliola are imitation marbles and are described in Plasterwork.

Well-designed and properly executed mosaic is a very beautiful decorative medium, and ranks among the most permanent as well as most pleasing wall-coverings. With glass mosaic great ranges both of colour and of texture of surface can be obtained, different methods of preparing the glass giving a brilliant granular or quite dull surface as desired to suit the particular position of the work. Marble mosaic is used more for floors and pavings than for vertical surfaces. Most mosaic is now put together in the studio and pasted upon sheets of tough paper to which the design has previously been transferred. The whole section can thus be bedded on the prepared wall-surface with the least amount of trouble and without any danger of its sagging. When the cement has properly set, the paper is washed off from the face of the work.

Much improvement has been effected in the design and manufacture of wall-tiles. Especially has the design of tiles reached a very. high level of excellence, and as a material which combines Tiles  the qualities of being hard in wear, durable, damp-resist ing and easily washable, with beauty of design, colouring and surface, tiling may perhaps be placed next in order of merit as a wall-covering to mosaic. A thin, opaque glass material, manufactured under various trade names, is now much used, especially for tiling existing walls. It has all the sanitary qualities of tiles, but is perhaps somewhat more fragile and liable to be damaged under hard wear. It is made in opal and other colours and is usually fixed with a special cement or mastic which allows for slight movements of expansion and contraction. The thickness of the material varies with different makers from s to 8 in.

Metal sheeting, though somewhat inartistic in appearance, is useful where a durable, waterproof and sanitary wall protection is needed, and is therefore often used for sculleries, wash-houses and Meta/ . lavatories. Thin sheets of zinc with slightly embossed patterns and enamelled in colours can be hung upon the wall with a composition of white lead (one part) and whiting (two parts) mixed to a thick paste with varnish or gold size. Sheets of iron or steel can be more elaborately embossed and fixed to the wall with nails or screws; they are either previously enamelled or are painted after being fixed. They are used more for ceilings than for wall-coverings, but are adapted for use in either position.

Tapestry of good design and workmanship is a really beautiful wall-covering. It is usually hung upon frames fitted to the wall,. and may either cover the entire wall surface or be fixed Tapestry  in the form of panels, friezes, dados or fillings. It is not at all a sanitary covering, for it harbours a very large quantity of dust and dirt. The same remark applies, but perhaps in a less degree, to brocades of silk and damask. These materials are of a delicate nature and become easily soiled by the fumes of gas or oil lamps. Substitutes for these materials on stout paper and on cotton are made with a prepared back to facilitate pasting and hanging, and are a very good imitation of the better material.

A coarse canvas, specially prepared with a smooth back for pasting, and stained in several plain colours, can now be purchased. Having a rough surface it naturally holds the dust, but this can easily be brushed off without damaging the material. It is a pleasing wallcovering, which will stand hard wear, and it forms a good background for pictures and furniture.

The term "wall-paper" embraces a very large variety of materials of many kinds, designs and qualities, ranging from the cheapest Wall- machine-printed papers of the most flimsy description and. often hideous design, to the Japanese and similar leather papers  papers, skilfully modelled in relief and richly decorated in gold and colours. The design of the paper, of whatever description it may be, should preferably be of a conventional pattern, unobtrusive and restful to the eye, and presenting no strong contrasts of colour. The wall must be treated as a background, consisting of a plane surface, and no attempt made to introduce a pictorial element into the decoration. The wall surface, regarded from the paperhanger's point of view, is often divided into three sections, the dado  or base, the field or filling, and the frieze at the top immediately beneath the cornice. This subdivision is not always adhered to, and a wall may be papered uniformly all over its surface, or may consist of dado and filling without the frieze, or frieze and filling without the dado. The division between the sections is usually formed, in the case of the frieze and filling, with a wood picture rail, and between the filling and dado with a moulded dado or chair rail.

Wall-papers may be printed either in distemper colours or oil  colours, and the patterns upon them are printed either by hand or by machine. There are also self-coloured papers which have different kinds of surface finish, and with some of these a pattern is formed by contrasting a smooth with a rough or granulated surface or vice versa. Typical of such papers are the ingrain papers, which have the colour penetrating through their substance. Plain filling papers are often used in conjunction with a boldly designed anal strongly coloured frieze of considerable depth. The dado is either of similar plain paper or of an unobtrusive pattern. Often the filling is taken down to the skirting without the intervention of a dado rail. Papers printed in oil colours can be sized and varnished, and when treated in this way can be washed repeatedly and are very durable. This treatment gives an unpleasant glazed surface to the wall, but in spite of this it is often adopted for bathrooms, kitchens and in similar positions, because it is economical.

The best papers are printed from blocks manipulated by hand. The pattern, or as much of it as is to be printed in one colour, is carved upon a pear-wood board, small and delicate members being represented by strips and dots of copper inserted in the block. With large blocks a treadle and pulley arrangement gives the workman assistance in applying and removing the pattern, which is first fed with colour by being pressed on a felt blanket soaked in pigment and then applied to the surface of the paper to be decorated. One tint is applied at a time, and this when dry is followed by others necessary to complete the design. This drying of the previous colour ensures sharpness of outline and accuracy of colour. Designs are sometimes worked on the paper with stencil patterns cut out of zinc sheets. These are laid upon the paper and thick colour applied through the perforations with a stiff brush.

The cheaper wall-papers are printed by machinery. The paper is made to travel round a large drum around which are grouped the printing cylinders, each with its separate inking roller to supply the special colour for its use. On each of the wooden printing rollers is set copper "type," representing as much of the pattern as is to be printed in one colour. It is a difficult and tedious matter to get all the rollers to work together to form one perfect pattern, and when printing in several colours it may take a skilled workman a week or more to "set" his machine, a very large quantity of paper being spoilt during the process.

The colours used for hand-printed work, whether applied with blocks or stencil plates, are much thicker in consistency than those for machine work. One advantage of hand-worked paper is the comparative ease with which a paper can be matched even after it has gone out of stock. At a slight extra cost the manufacturer will print a few pieces for his customer from the blocks he has retained. With machine-printed paper this, from a practical point of view, is impossible, for it would necessitate the printer's going through the long and costly process of "setting" the machine.

W all-papers are sold in rolls called "pieces." In England the standard size for a piece of paper is 12 yds. long and 21 in. wide. The printed surface is only 20 in. in width, as a margin of half an inch is left on each edge. One or both of these plain margins must be removed prior to hanging. French wall-papers are 9 yds. long and 18 in. wide and only contain 402 sq. ft. compared with 63 ft. in a piece of English paper. To ascertain the number of pieces required for a room take the superficies in feet of the surface to be covered (deduction being made for the doors, windows, &c.) and divide by 60. This gives the net amount required; an allowance of about oneseventh must be added to allow for waste in matching patterns and of odd lengths. If French papers are to be used the division should be 38 instead of 60, these figures representing in feet the area of the printed surface in each roll. The surface of the wall should before papering be carefully prepared so as to be quite smooth and regular. If the wall has been previously papered it should be stripped, and any irregularities filled in with stopping. To remove varnished paper use hot water to which borax has been added in the proportions of 2 oz. to each pint of water. In selecting a paper for a newly plastered wall the colour chosen should be capable of withstanding the bleaching action of the lime in the plaster. Greens, blues and pinks especially are affected in this manner. For heavy papers glue paste should be used. Papering which has become dirty may be effectually cleaned with new bread or stiff dough; when gently rubbed over the surface in one direction this speedily removes the dirt. When the wall is damp, tinfoil, pitch-coated paper or Willesden waterproofed paper is used behind the paper to prevent the paper from becoming damaged by the wet. (J. BT.)