TO BEGIN A RELIEF TILE, a model should first be planned on clay or modeling wax. A pencil pattern is first made on paper and this paper is placed over the layer of clay or wax and a pencil tracing will produce an indented pattern of the subject on the clay or wax underneath.

TO MODEL THE SURFACE a wooden modeling tool, such as is used by sculptors, or a leather modeling tool or even small whittled pieces of wood can be used. In producing raised portions the clay or wax scraped to produce low parts can be used and care should be taken not to produce too great a relief as a tile design should not appear detached.

AVOID UNDERCUT SURFACES or overhanging edges on the finished model as this will result in locking of the cement cast with the plaster mold and breaking of the tile before it can be removed. A general checking over of the different parts before the plaster cast is made will avoid many of the overhanging parts going through as they can be easily located and corrected.

TO CAST THE PLASTER MOLD the clay or modeling wax is surrounded with the retaining bars and as the clay or wax needs no oiling the plaster can be mixed and poured into this mold. A slight jarring of the table or surface on which the mold is placed will cause the plaster to settle, producing a level surface and also cause any bubbles to break or come to the surface.

TO AVOID BUBBLE DEFECTS IN CASTING either with plaster or cement the plaster or cement mixture should be poured into the center location of the mold allowing it to spread gradually toward the sides and corners carrying the air in the grooves and low spaces, forcing it toward the edges. Once the surface is covered in this way the remainder of the mixture can be poured in more rapidly.

TO CORRECT BUBBLE DEFECTS that appear on the finished plaster or cement casting, scrape some of the plaster or cement from the back or sides where it does not matter and repair the flaws by pressing it into the holes. Where cement is repaired this way it should be permitted to dry for another day before it is placed into water to harden.

TO MAKE THE CEMENT RELIEF TILE in color the plaster cast made from the clay or wax model should be oiled after it has been shellaced and surrounded with the retaining bars. The color should be then mixed with the cement and water added to make it of a pouring consistency, it is then poured into the mold. After this color has set for awhile the back layer is added of concrete after the color of the first pouring has been carried up so as to produce color on the sides as well as on the face.

WHERE A NUMBER OF COLORS ARE USED the colors are mixed and dripped upon the oiled surface of the plaster mold before it is enclosed with the retaining bars, as the retaining bars would prevent free access to the surface with the brush. After the various colors have been placed, the plaster cast is then placed within the bars and the color being permitted to set, it is then backed with a layer of concrete.

THE CONCRETE BACKING MAY BE COLORED either with color throughout or with a topping of color to give it a finish. If corners are to be rounded or the edges trimmed in any way this color layer should be thick enough to permit trimming without exposing the under layer.

TO AVOID THE COLOR FALLING OUT in color relief work, the following should be observed. When preparing to pour in the backing, observe whether any of the color cement placed on the tile has become too dry. If so, it should be sprayed with a light coating of water or brushed with a brush full of water, and its upper exposed surface slightly roughened so that the backing will adhere firmly. If it becomes dry and smooth the second layer of cement poured onto it will come in close contact but not adhere, and later a change in temperature or jar of the tile may shake a portion of the design loose so that a color fragment will fall out.

TO AVOID COLOR PREMATURELY DRYING, the plaster cast should be placed in water for fifteen minutes at least before the color is placed into it. To permit free absorption of water the plaster tile should never be shellaced on the bottom but only on the sides and the top.

ANOTHER WAY TO MODEL A RELIEF DESIGN is to carve it on plaster direct without making the relief on clay or modeling wax. This method has the advantage of being proof against overhanging edges, though some care must be taken against undercut surfaces.

TO MAKE THE PLASTER CARVED MODEL trace the design onto a smooth slab of plaster of the right size that has been cast on a smooth surface. If a larger piece of plaster than the desired size is used it can be cut down.

TO CUT PLASTER SECTIONS an old saw can be used or several strokes of a knife on the surface until about one-quarter of the thickness has been cut, and a similar cutting on the reverse side, just opposite to the cutting on the first side will enable the plaster to be broken easily. Or by laying it on a straight edge with the line of cutting over the edge, a quick pressure with the hand will snap the two pieces apart.

AFTER THE DESIGN IS TRACED a chiseled nail point, nut pick or other hard edged point is used for scraping the surface of the plaster, modeling it or carving it to the desired shapes. Naturally it will be found that plaster can only be taken off and not added on and that all reliefs must be produced from the surface downward, that is the natural surface will be the maximum height and all variations in the surface produced below that.

BACKGROUND TREATMENTS are produced where a design appears in low relief against a background. The background may be stippled with the tool point or lines scraped or crossed lines used to create interesting background qualities.

TO BUILD UP PLASTER SURFACES, roughen the surface onto which more plaster is to be placed and mix fresh plaster and place it on with a small spoon or with the brush. After this is dry it can be carved or scraped with the tools used in the modeling of plaster.

TO FINISH THE PLASTER CARVING, it is dried, shellaced, and used for casting just the same as the other relief forms described. To preserve casts from receiving injuries to their surfaces they should be wrapped in paper with a card against their face and placed with face toward the wall in a cupboard or shelf, when not in use. Where a mold has been repeatedly used and the shellac become worn, the mold should be carefully dried and the shellac coating renewed.

A CONVENIENT CLAY TO USE for relief work is the powdered fire clay secured in most hardware stores and is the clay used for lining grates, furnaces and similar purposes. This clay is convenient in that only the amount needed may be mixed up for use, leaving the balance of the powdered fire clay always in good condition.

RELIEF TILES DESIGNED FOR FLOOR SURFACES or for wall surfaces are best where they do not contain deep relief as they will not catch dust or dirt and will be better unified with the remaining surfaces.

SPECIAL TREATMENT FOR RELIEF FLOOR TILES is required in that the cement should be compact and clean sand should be used mixed with just enough water to cause the two to adhere to each other and this should be tamped into the mold well up against the face of the plaster tile to pack the mixture firmly and cause it to form into a durable surface.

TO HARDEN CEMENT TILES or pottery they should be placed in water so that the water will complete the chemical action producing the stone-like quality of successful cement work. If the tile is removed and dried and again placed in water it will increase the hardness.

AFTER THE TILE IS HARDENED it is dried thoroughly and brushed well with a brush. It may be waxed or first given a thin coat of shellac and then waxed. Shellac should never be applied until the cement tile is thoroughly dry, as otherwise the shellac will remain sticky.

MAJOLICA POTTERY derived its name from the island of Majorca, Italy, where during the sixteenth century glazed pottery reached its highest perfection.

Glazed color may be placed in hollows in the surface of pottery or on the surface. A better method is to produce a raised line or rim to retain the glaze, and this is the method we will use in the cement or concrete pottery.

THE CEMENT MAJOLICA TILE is made as follows: First design a subject that will have each motif, part or section defined with lines. These lines must be part of the design and used much as lines are used in stained glass work. The design should be simply planned. A confusing overcrossing tangle of lines is to be avoided. A few geometrical forms rightly related will be most pleasing. Keep the design at least one-half inch within the edge of the space. Then oil a piece of glass as directed, place over a card that has the tile dimensions squared off on it as a guide for placing the casting bars on the glass. Clay or wax should always be used to hold the casting bars in place. Into this now pour plaster-of-Paris, pouring into the center, letting it flow to the outer edge. Level off evenly and remove after fifteen minutes. On releasing this plaster tile a smooth surface will be found on the side which came next to the glass.

THE DESIGN is then transferred to the plaster tile by tracing with a carbon paper. The paper should be thumbtacked onto the sides of the plaster tile to prevent it from slipping while tracing. The design should also be traced on backwards so that the completed majolica tile will be in the same position as the design. The design is then incised with the incising tool, care being taken that at whatever depth the line is made the incision has sides sloping upward. If these grooves have overhanging edges the cement to be poured in will flow under these edges and lock the tile, causing these lines to break before the cement tile can be released.

WHEN INCISING, see that the bottom of the groove is sufficiently wide, as this bottom is to be the surface of the line on the completed surface. A line one-sixteenth or one-eighteenth of an inch is not too wide. The plaster should not be too soft or too hard to secure the best incision and avoid crumbly lines. When the incising is completed oil the surface and surround the tile with four retaining bars. The bars should be soaked in water and be of double width as they extend above the plaster cast. This extension above the tile represents the thickness of the tile to be made. Clay or wax is pressed on the outer edges of the bars and plain neat cement or a mixture of the desired color is made and poured onto the mold. Pour in the center steadily, for cement poured on the “installment plan” will show a mark wherever each installment occurred.

When the cement in the mold has dried for twenty-four hours remove by slightly prying, after the retaining bars have been removed. If parts of the lines are not on the surface it is because air was arrested in pouring the cement or the oil settling in the grooves. If lines are broken and remain in the mold it is because the grooves have overhanging edges and locked the cement line. To repair these lines, soak the tile for a few minutes and mix a small portion of cement to match that used and build the missing section by dripping the cement from a brush.

AFTER DRYING for an hour put the whole tile in water for a day or overnight and it is then ready to add the color. Meanwhile the plaster mold with the defective grooves should have the grooves cleared by scraping the overhanging edge with an incising tool.

The tile as it has been produced by the mold appears with a number of relief lines dividing the whole surface into a number of partitions or cells. It is into these that we are to place the color and it should be worked as follows:

While the surface of the tile is moist, drip in the color with a brush, spreading it to fill the required space. Thin pieces of metal (or material that will not absorb the moisture) may be used to spread the color, producing a smooth, even surface. The color after once commencing to set should not be touched, and for this reason should be rather liquid so as to permit handling without too rapid drying.

THE COLOR SURFACE appears better when the lines of the design remain uncovered with color. If the color is thickest in the center of the spaces and then bevels down as it comes in contact with the lines, the whole tile or surface will appear more professional.

If color becomes blurred or disturbed, it is better to wash the whole out under the faucet and begin anew, or remove the section at fault and work over. No amount of patching or rubbing will perfect the surface after it is partly dry or completed.

After the coloring is finished put in a tray, carefully pour water into the tray without dropping any onto the tile and let harden for five days. The water should reach a little more than half-way up the side. After removing it from the water let stand until dry, polish with a soft flannel slightly waxed to remove white sediment on surface.

ANOTHER METHOD WITHOUT THE LINES is to use the color directly onto cement or concrete surface without any retaining lines. The colors may be placed so that they intermingle or so that they just touch, or the color spots may be separated one from another similar to stencil work. The color for this method is mixed thoroughly with cement and water until the mixture is a fine thick liquid or “slip.”

SLIP PAINTING is a method of painting a design in one or several colors over a cement or concrete surface. The color may be slightly in relief or if done at the proper time it can be made to become a flat stain of color sinking into the first surface.

THE TWO WAYS OF SLIP PAINTING must be handled a little differently and the best way to become familiar with these methods is to do the work. Therefore let us work out the first method of producing a design slip painted in slight relief as follows:

FIRST: Make a design for a six-inch square, the design to denote the colors to be used. Second: on a glass place retaining bars which have been soaked in water and oiled, leaving space six inches square into which a half layer of neat cement is poured and then a layer of one-half sand and one-half cement. Third: after standing for twelve hours, release this cement tile and it will be a plain, smooth surface. This is placed in water for an hour and the design traced upon its surface.

Chalk of any visible color should be rubbed on the back of the drawing to act as a tracing medium. Carbon paper or graphite should not be used as any greasy substance will prevent the slip painting from adhering to the cement tile surface.

THE COLORS FOR THE SLIP PAINTING should be mixed so as to match the colors of the color sketch. When matching the colors, dry a small dab of each color on a glass to see the dried color effect.

TO MIX THE COLORS PROPERLY, select the color you wish, emptying a little upon a glass or marble slab. Take a little clean water and mix with a palette or putty knife and grind the color until it becomes a thin liquid paste. Having ground this color thoroughly, scrape it up and place on one side of the glass, then proceed with the next color until you have mixed the complete palette of colors to match those on the sketch.

VARYING COLORS CAN BE SECURED by mixing the mineral colors and where hues different than those in the set are wanted they should be mixed the same as in water colors. There is one exception to this rule and that is in using the orange. The orange in the mineral colors when mixed with blue will produce a violet.

To gray the colors add gray cement, and to lighten the colors add some of the white cement.

TO PLACE THE COLOR ON THE TILE, take it up with the brush and drip onto the cement surface, being guided by the tracing previously made. The color should be thin enough to flow from the brush easily and not so thick that it drips in lumps. More water should be added if too thick and more color is added if too thin. In both instances, whether water or color is added it must be ground in thoroughly. If the color settles on the glass it should be stirred again to keep the mixture uniform.

THE RELIEF OF THE COLORS can be regulated by how much color is flowed from the brush, and surfaces can be built up by repeating the strokes of color. Avoid repeating a stroke after the color has commenced to set, as a second stroke in such an instance will destroy the surface lustre. Where colors run over the boundaries they may be scraped back or taken off with a moist, clean brush.

The direct clean stroke will produce the best final results, and if preceding each stroke a little thought is given, mistakes will be avoided.

The tile surface should not be permitted to dry while working upon it and if kept in a shallow tray of water there will be less risk of it doing so. Water should never be permitted to fall upon or touch the surface of the slip painting or tile as the color will be destroyed. The tile is placed carefully into shallow water to continue hardening and in four or five days will be hard enough to remove. After drying out of water several days it is ready to use or it may be given a gasoline wash or wax rub if needed.

Tiles will harden as they age. Those that appear to be partly chalky when completed will harden in a month’s time, when the moisture from the center of the tile has completely evaporated.

THE SECOND METHOD OF SLIP PAINTING is used where three different planes or heights of color are wanted. For instance we will suppose that the subject is to be a decorative design of trees and distance landscape in three colors. This would be worked out as follows: First, cast a plain cement tile and after removing it and while damp pour a spoonful of color on the surface coating it with plain color as desired. This color should be the background color of the sketch. Second, while this coating is soft, take the lightest color (for clouds, water, boats, flowers, etc.) and with a full brush place the color onto this soft coating. It will blend and sink into the background color and remain equally flat. Third, after these colors have commenced to set, with a full brush paint in the foreground part of the design (trees, etc.), working in large masses and building up the color by repeated strokes until the right relief is secured. Avoid shading the parts and keep all parts flat in tone, even though they may be in relief. It will be found that the later color is added to the first coating the less it will sink into the background. Any design can be worked out accordingly either in relief or flat. A little experimenting will solve many questions, and reveal greater possibilities. To complete the tile it is placed in shallow water until it hardens, then let dry for several days after which it may be given a toning wash, or gasoline wash, and a wax rub.

A THIRD METHOD is to take a flat surface and slip-paint a design onto it in relief. After the color has set for a short time it can be trimmed carefully with a knife so that the sides are nearly vertical. This will give the slip-painting a decidedly different appearance and it may be left this way or other color may be added so that it comes nearly up to these trimmed sides.

AVOID LEAVING ANY PART OF THE SURFACE DRYING or setting when painting on the surface; or the tile hardening in the water too long before being painted upon, as it will prevent it from becoming durable. Surfaces can be covered smoothly when slip-painted if the color is used very thin. First cover the surface with a coating of the color to be used, immediately adding more of the color and it will flow and settle evenly.

A slip-painted color will dry dull if placed upon a tile shortly after it has come out of the mold. To secure a glaze to a color the tile should remain in the water for two days before the color is placed onto it.

FOR LARGE SURFACES on which color is to be slip-painted, the surface on which the color is to go should be roughened, so that the color will become anchored.

THREE DEGREES OF SURFACE can be secured by different treatment. These finishes are, first, Dull Surface; second, Mat Surface; third, Glazed Surface.

DULL FINISH is secured by putting the color into the mold. The mold absorbing the water from the surface causes it to dry dull.

MAT FINISH is secured by placing the color onto the tile or vase surface after the surface has come out of the mold and moistened in water for a few minutes.

GLAZED SURFACE is secured by letting the tile or other object harden in water for several days and then draining off the surplus water, after which the color is slip-painted onto the desired surfaces.

TILE SHOULD NOT BE PERMITTED TO DRY at any time before color is added, as the color will not become attached to the surface.

DO NOT FORGET to roughen the surfaces of the spaces and to add neat cement also before dripping the color onto either the mat finish or glaze finish tiles as described in chapter five in the paragraph on The Glazed Color Finish.

SGRAFFITO is the name applied to the incised ware of the Italians, and used by them from a very early period dating as far back as the twelfth and thirteenth centuries. The ware was made by covering the clay body with a layer of slip of another color, and this was then scratched through with a tool showing the color of the ware beneath against the superimposed surface, after which it was fired. This process has been used from the most primitive times, but it remained for the Italians of the fifteenth century to dignify it as an art.

COLOR CEMENT SGRAFFITO is produced with a layer of cement and color being used instead of colored clay and the cement is hardened without firing, water only being used to finish the surface to a durable quality.

THERE ARE TWO WAYS to produce a sgraffito surface on a tile and these are, the glazed surface and the dull surface tile. No mold is needed for the design as a sgraffito design must necessarily be a freehand production, though molds may be used for duplicating the sgraffito effect after the original one has been made, if no undercut edges are left.

TO PRODUCE A SGRAFFITO TILE, the retaining bars are set to give the desired shape and dimensions, after which the space is filled with a half inch layer of concrete, either of sand and cement mixture or of gravel and cement. When this layer has dried so that the top section is moist but firm in surface, a thin layer of color and cement should be poured onto the cement so that it forms a thin layer not more than an eighth of an inch thick.

TO SMOOTH THE LAYERS after the color has been poured in, shake the glass or table or whatever surface the mold is resting upon and if this is done gently it will cause the color to become level and even in surface finish.

TO CAUSE TILES TO BE EQUAL IN THICKNESS the surface of the glass or table upon which the mold rests should be level when the cement is poured in. Otherwise the tile when finished will be found to be thicker on one side than on the other. A glass or pan of water or a spirit level will quickly show whether or not the surface is level.

AFTER THE FIRST COLOR LAYER IS POURED into the mold it is permitted to stand just long enough to settle firmly and then a second layer of another color is poured over the first layer so that it also forms a thin layer of even color. This second layer should be even thinner than the first. A layer one-sixteenth of an inch is a good dimension to plan on, though these dimensions need not be accurately adhered to. If the first layer is permitted to dry too long before the second layer is added the result will be that as the finished sgraffito tile is drying it will split in layers, the split coming between the layers of colors that were permitted to dry too long.

A THIRD LAYER OF COLOR may be added over the second layer if the design being planned calls for three divisions of colors. These layers are to respond to the next step in the process, which is to expose portions of each layer by tooling the surfaces so as to produce different colors at the same time that the different depths are produced.

THE TOP LAYER WILL DRY WITH A SMOOTH SURFACE which will produce a sgraffito tile with a glazed or partly polished surface while the other layers will have a surface with dull texture.

TO PRODUCE A TILE WITH A DULL SURFACE throughout, the pouring stages should be reversed in their steps. That is, the color that is to be the top surface should be poured first and the other colors in their proper relation, the last layer being the cement and sand or other concrete mixture. This will result in the layer first poured in coming next to the glass, having a dull finish when it is released from the mold.

TO PRODUCE THE SGRAFFITO DESIGN on the sgraffito tile, the tile should be permitted to dry for about ten to twelve hours or if it remains overnight the surface will be about right to work upon. The paper with the design is then placed and retained in the correct position on the cement tile and a dull pencil is used to trace the pattern, without the use of carbon paper or other transfer medium. This will result in an indented or embossed guide line on the cement surface of the tile which can be used in scratching away through the first layer to the under color.

THE TOP LAYER OF COLOR should be used to tell the main part of the design story. If the subject is to be that of a bird or a ship, the top layer design should be the bird or ship or other motif and the motif should be so designed as to reach the boundaries of the tile surface so as to produce a strengthening border arrangement all around the edge.

THE SECOND COLOR LAYER can then play a secondary part in both the color scheme and the design arrangement, giving with its color placing a contrast to the upper main layer used for the design.

THE BACKGROUND COLOR should be brilliant or dull depending upon the surface color. If the surface color is brilliant, the bottom color should be duller. If the upper color is dull, the background color can then be the bright intenser color.

WHERE THREE LAYERS OF COLOR ARE USED the middle layer can be a color harmonizing with both the background layer and the top layer and can be used either for a pattern part to the design or it may be used simply as a blending strata or layer appearing in the cut sides of the sgraffito work.

COLOR HARMONY is essential in producing sgraffito color cement and a color sketch will be a good safe preliminary in doing sgraffito work as false steps or errors cannot be remedied in sgraffito and each step should be carefully thought out before the tooling commences.

TO DO THE TOOLING, a scratch point should be used for incising or scraping down along the line of the portion to be scraped out. The portion within this boundary should then be scraped out down to the next layer of color, care being taken not to gouge or cut deeply into the under color. If the design is one of three layers, the center layer can be included in the scraping out if the bottom color or layer is to appear in that portion of the design. Do not attempt in the scraping to take out large portions at a time as it will result in the breaking out of sections that are wanted as part of the remaining design. It will be found that the layers of color as scratched into retain their separate layers and that the thin layer of the upper color separates easily from the layer on which it rests. If a slight portion of the upper color is inclined to remain attached to the background color or under layer let it remain as it will give an interesting color quality and harmonize the two colors.

THE SIDES OF THE SGRAFFITO LAYERS should gradually slope outward, and after the layers have been tooled clear the sides of the layers should be gone over and evened up in slant as well as in general finish. If the corners are to be sharp or rounded in finish, see that the treatment is carried out similarly in all parts so that a general unity of finish will remain.

THE LAST STEP IN FINISH is to place the sgraffito tile in water so that it is entirely immersed, and it is left in the water for several days after which it is dried by being placed flat in a cool but not draughty place to dry.

TO PRODUCE SGRAFFITO SURFACE on bowls or other round surfaces the layers are produced by rotating the bowl in colors or spraying the colors on with a sprayer such as is described in the chapter on coloring of bowls and vases. The color can also be placed on with a brush if it is mixed to the right consistency and the successive layers put on at the right intervals.

SGRAFFITO FOR ARCHITECTURAL WORK holds great possibilities, and is being gradually recognized by those builders who desire the charm of hand wrought enrichment that graces so many of the Old World buildings. Sgraffito decorative pillars and panels for buildings, homes and courts is an assured possibility by the use of color cement and can be produced with less cost than by the fired clay method as well as in larger, more unified sections in that there are no kiln limitations to be considered in doing the color cement. A plate is shown illustrating the use of sgraffito in the making of an entrance to a college building designed in the Italian Renaissance style and the sgraffito and ornamentation being of Italian source, both combined in perfect harmony with the building as a whole.

SGRAFFITO CAN BE APPLIED TO MANY FORMS such as book ends, fern boxes, garden bowls, the requirement for success being mainly the placing of the successive layers of color on each other when neither too dry or too wet, and the scraping away of those parts desired when the cement is in the proper condition.

FROM A STANDPOINT OF GOOD DESIGN modeling, when applied to a flat surface or any other surface, should not be high in relief.

Any time that a modeled design appears to have been added onto or is in such relation to the surface that it appears to be an independent, detachable ornament to that surface, then it is not truly decorating the surface, but detracting from the object decorated.

At all times keep the principles of unity and subordination in mind when producing modeling so that the design will be a related development to the material and the surface used.

CEMENT TILES WITH A MODELED SURFACE are produced as follows: Take a flat, smooth piece of clay or modeling wax, cut to the size of the tile to be produced. Such a surface may be made by rolling clay or wax with a rolling pin or other rounded surface. Having drawn the design to be modeled on a piece of thin paper, place this over the clay and trace lightly. This will produce a slight indication on the surface sufficient to guide the modeling. If there are sections that are to be low, these parts are outlined with an incision in the surface and scraped out to the desired level.

Do this over the entire surface, bearing in mind that the edges of the tile should generally have a border or other parts retained of the original surface. Too much elimination on the tile edge will thin the tile and weaken its construction and design.

Having scraped out all the low parts, then clay or wax may be added to such parts that are to be higher than the first surface. With the modeling tool shape the parts, finishing them so that there are no overhanging edges.

When this is completed surround with the plaster bars and produce a mold in plaster which in turn is oiled in the usual way and a cement tile cast from it. Neat cement should be poured first, and after a few minutes setting, a concrete mixture is poured in until the desired thickness is secured. In this way a cement tile is secured, duplicating in form the original clay or plaster hand-made modeled tile. The color of the surface can be any color according to the color added to the neat cement mixture.

DIFFERENT COLORS on different parts of the surface can be produced as follows: Mix cement colors with equal parts of cement. Grind these colors with the putty knife or pestle and place each color in a small saucer or pan. Oil the surface of the mold with a brush, dabbing it on in short strokes. The colors are next dripped from a brush onto their right location. This layer of color should be about a quarter of an inch thick and left to stand until firm on the surface. It is then covered with a layer of concrete and smoothed off to a level.

TEA TILES OR LARGE TILES for inserts into garden furniture or for architectural use can be strengthened by a reinforcement. A reinforcement may be made from the ordinary window screening or any wire fence mesh or so-called hardware cloths used in building construction.

This wire should be cut a little smaller than the tile and sunk into the concrete layer while soft. It should be pressed down with the fingers until the concrete closes over it. This will add a considerable strength to the tile.

After the tile has set for several days, it is removed by inserting the knife between the edges and carefully prying it apart, or steaming apart by placing over a low flame for a few seconds. If part of the color remains sticking to the plaster mold it is because there was not enough oil on that particular spot. Therefore remember that a mold surface should be well oiled before placing the color into it, and care being taken that there is not so much oil that it settles in the hollows and grooves.

The tile after drying thoroughly may be polished with wax and used.

FOR MODELING LARGER OBJECTS such as flower pots, urns or similar forms, it is best to form some means of reinforcement to approximate fairly closely the final form of the object. Close meshed wire can be used successfully for this purpose. It should be tied and braced firmly so that the concrete or cement weight will not destroy its shape. The concrete mixture should be made with one part cement and two parts clean sand.

TO HASTEN THE SETTING OF CEMENT add a very small quantity of common washing soda to the water used in mixing the cement. This will cause the cement to set up rapidly so that the work can be done more quickly.

AFTER THE MIXTURE HAS BEEN APPLIED over the wire reinforcement and shaped and modeled until completed, it should be put in some covered place or in a moist location for the first two or three days so that the moisture in it will not evaporate.

TO HARDEN THE CEMENT OBJECT immerse it well in the water for four or five days. If it stays longer in the water it will not hurt the object. The water will harden or complete the action of hydration necessary to make cement durable.

TO SECURE BISYMMETRIC SHAPES to forms or to secure true circular shapes, a templet of sheet metal can be cut and rotated from a centrally located axis. This is used while the mortar or concrete is in plastic condition so that the templet will cut or model the right contour.

CARVED CEMENT is made possible by scraping or carving out the cement when it is in the right condition. This condition can be determined by scraping the cement to see whether it is hard enough to carve. If it is too hard, it cannot be carved successfully. About sixteen to twenty hours setting will produce about the right condition but this will vary according to the mixture and climatic conditions, as temperature will be an important thing to consider in all color cement work. Very hot weather is not a good time to do color cement, the winter days or gray cool days are best to work with cement for perfect hardening results. Avoid freezing weather.

TO CARVE CEMENT, the tools may be of metal or nails shaped with cutting points and the work done similarly to the carving of the sgraffito tile described in the previous chapter. No adding or building of parts is possible, the whole subject being a process of taking out parts and shaping the parts that are left. Backgrounds and portions can be varied in texture and different results will be secured with a little experimenting.

DIFFERENT TEXTURES are possible in the carved tile. A glazed surface to the carved tile is secured by carving on the upper side of the tile; while the dull under surface, the side molded against the glass or under surface, will be used if a dull surface for the carved tile is desired.

A GLAZED OR MAT FINISH BACKGROUND in the carved tile can be secured by immersing the tile in water for a day or two for glazed finish or an hour for a mat finish and then applying neat cement, plain or with color as described in the chapter on Color Work for Tiles.

CARVING ON BOWLS AND VASES and other forms can be done, care being taken that the carving does not go so deep as to weaken the surfaces. Motifs or spaces can be carved out of cement bowls and vases and bits of stained glass or mosaics, or color cement can be put into the spaces and neat color cement used to bind the additions into the spaces.

SLIP-PAINTED PORTIONS MAY BE ADDED to the carved tile. After the tile is carved and properly moistened in preparation for the cement to be added, the color cement is mixed to a thin slip and a background pattern or decorations can be added to the surfaces of the carved tile. The tile is then placed in shallow water without permitting the water to reach the surface of the tile, and permitted to remain for four to six days before removing. It should then be placed in a cool location until completely dried.

THE UNIT TILE or the small tiles made to be assembled in patterns, may have modeled or carved cement surfaces combined with the units to complete the pattern. For instance a number of tiles representing leaf forms may be combined with others representing flower motifs. These may be imbedded into a panel of cement or concrete, the units grouped in some form of design growth, the stems and other related portions being modeled in the cement, or carved in the surface after the cement is somewhat hardened. The units can be in color or mat finish, the background remaining in dull finish.

MODELED CEMENT TILES differ from the cement tile with a modeled surface. In the first the modeling is done on wax or clay and the cement tile is made by duplicating the effect by the use of plaster molds. The modeled cement tile is a modeling of the cement by hand while it is still in a plastic stage.

TO PREPARE CEMENT FOR MODELING, pour a concrete mixture into the mold so as to allow for a second added layer of about one quarter inch of neat cement. This last layer of neat cement is the part which is to be modeled and can be made into a color by the addition of color to it. This color should be added in the dry form to the dry cement, mulled or ground well into the cement and then mixed with water until it becomes a thick cement paste that will pour slowly onto the concrete mixture first placed in the mold, until it covers the entire surface. A gentle jarring of the mold will settle the color evenly and it should then be permitted to stand until of a good modeling consistency.

A GOOD MODELING CONSISTENCY for cement is determined by testing it with a tool or small pointed stick making a small incision or trying a small section to see if the mixture holds its form. If the cement as laid up on edge stays in position and does not have the tendency to fall or settle, it is then ready to model, as it will hold its form when built in relief.

PROMPT ACTION IS NECESSARY when the mixture is at this point and the tool should be promptly used scraping or sketching the subject by incised lines in the surface. Then parts of the cement are scraped from the low portions and placed on the parts to be in higher relief until the general rough forms are massed in. The smaller parts are then detailed in and the different parts finished just as one would in working with clay or modeling wax. If it is found that parts do not hold up, it is because under sections of the cement have not dried sufficiently and it will be necessary to wait until it hardens a little more.

THE FINISHED RESULT may be complete with the strokes of the tool or the modeling instrument showing over the entire surface.

If the technique is shown in this way, care should be taken that the strokes are pleasing in direction and not carelessly left. As the tile hardens it will be found that the surfaces or edges can be shaped, and even when the surface is almost hard, it can be slightly indented or carved to produce different textures and varying qualities.

GOOD MODELING TOOLS are those that are made from pear wood for sculptors use. Metal modeling tools also can be used. Good home-made modeling tools can be made from manicure sticks, pencils, dowel sticks or ordinary small hardwood pieces shaped with a knife. These pieces should be smoothed down very evenly with fine sandpaper and then rubbed with beeswax or paraffin to avoid any rough surfaces. Rough surfaces will cause the cement to stick to the tool. Experience will be a good guide to the worker in color cement for determining the best shape to make the modeling tool, as individual needs and ways of working will determine the best form for each person.