Part 10

It is easy to make any article of _papier-mâché_ if the mere beginning of a form has once been shaped; because, after that is set, all that we have to do is to gradually paste one piece of paper on, here and there, till it is finished. This beginning is very easy if we have an object on which to begin. Thus take a vase or cup. Oil this, and then lay on and all around it soft, damp paper. Newspaper will do--a _soft_, white printing paper. Then, with a broad brush, lay on paste, and apply a second coat of paper. Press it meanwhile as hard as you can. Continue this till the _papier-mâché_ is thick enough. When dry, take a penknife and cut a line through from top to bottom. Scale it off, and reunite the edges with strong glue; then paste over the line of junction a strip of paper. Then you will have a cup.

If it be rough, cut it smooth and use glass-paper. When finished it may be painted or covered with wet leather, which can be worked into relief. Or it may be made to look like ivory by the process elsewhere described. Paper may in this process be combined with soft leather rags; as, for instance, pieces of old gloves out of which the thread has been taken, old chamois, bookbinders’ clippings, or the like. This forms effectively leather.

CARTON-PIERRE, or stone-paper, is a very useful composition, which is very fully described by GEORGE PARLAND in _Work_, July 2, 1893. It consists of paper scraps, in the proportion of an ordinary washing boiler or copper one-half full of boiling water and about one-half paper waste. Add two pounds of best flour-paste; also, in a separate vessel, a quart of water, into which sprinkle a handful of fine plaster of Paris. Let it stand ten minutes before mixing it. “When the paper in the copper has become a fine pulp add the flour-paste, keeping the whole well stirred. Fifteen minutes after add the plaster, and a few minutes later rake out the fire from under the boiler. Have ready three pails of fine ground whiting; pour in one pail of whiting and stir up well, adding more whiting till the stick used to stir will stand of itself in the mixture. Let it cool, and it will be ready for use.

“Some firms,” writes Mr. PARLAND, “add powdered alum in the boiling process, others add one pint of boiled linseed-oil; but if made according to the previous directions, an excellent _carton-pierre_ will result, which gives very fine impressions from moulds. If it be cast in a plaster mould, the latter should have two or three coats of shellac varnish, and then be well oiled.... In using the _carton_, sprinkle some fine plaster of Paris on a bench, and taking a lump of the newly made _carton_, mix it well with dry plaster, adding more plaster, as bakers would add flour to their dough. Having worked it well in this way until it will not stick to the fingers, with clean hands roll pieces very smooth in the palms, or on a smooth level board, and press each roll into the cavities and hollows of the mould, _often wetting the edges of the carton_ in the mould before adding a fresh piece to it. The casts must not be more than from an eighth to a quarter of an inch in thickness, except at the outside edges of the mould.... The casts must stand about twenty-four hours, and then be baked in not more than 100° heat.”

The reader who is specially interested in _papier-mâché_ will find a series of articles on the subject in _Work_, Nos. 3, 6, 12, 17, 22, 25.

Pipeclay, to which calcined magnesia, whiting, or baryta may be added or omitted according to the body required, may be combined with _papier-mâché_ and gluten, such as gum-arabic or dextrine or flour-paste, which will form under pressure, or even by hand-rolling, a very hard and finely grained substance, which is specially adapted to painting pictures. Plates or _tavole_ are sold very cheaply in Florence of _papier-mâché_, which are as hard, heavy, and glossy as ebony. It is not generally realised that an expensive hydraulic-press or steam-engine is not needed by the amateur to harden _papier-mâché_. A common bread-roller, passed many times over the material, will work it “down and in,” quite as well as direct pressure, and very often much better.

_Papier-mâché_ mixed and macerated with indiarubber or gutta-percha and benzole (_vide_ Indiarubber) forms in many cases a very good substitute for leather. It can also be combined with _flexible_ varnish to make leather. Very valuable soles can be made, or broken ones repaired, by taking card or pasteboard and soaking it in a hot solution of indiarubber. These waterproofed soles, whether of cardboard or leather, are easily prepared, as easily applied and renewed, and they will keep the true sole from wearing out forever, if renewed.

Singular as it seems, there are not many persons who are familiar with the properties or texture of so familiar a substance as paper. We know that if wetted it grows soft, but still remains, as it were, knotty, and that when chewed it does not properly dissolve. Yet if the reader will take a piece of thoroughly wetted paper, and knead or macerate it with a knife for some time with gum in solution, he will find it gradually becomes a soft paste, as flexible and as capable of moulding as putty or clay. This is not the same as _papier-mâché_, which consists of paper merely wet or mixed and boiled with paste, and contains fibre and knottiness. The finely macerated paper, combined with an adhesive, is ductile, impressionable, sets well, and readily receives pressure on rolling, under which it becomes extremely hard. Paper thus _completely softened_ is readily made into sheets, and may be easily applied not only to fill up worm-holes in leaves and completely torn-away corners, &c., but is very useful for cracks and cavities in wood and other substances. It may be made up with any gums, such as gum-arabic, dextrine, fish-glue, and also with caseine, gutta-percha, varnish, and most of the substances used in cements. Paper when thus softened and mixed with, _e.g._, fine glue and glycerine, or with flour-paste, can be moulded and applied in ornamental forms to any surface.

There is this great difference between simply _wet_ paper, however wet it may be, and that which is completely softened by maceration. The former is always lumpy, the latter passes under the blade of a knife like soft clay or putty. When made up with gum, glue, and glycerine, or strong paste, it is, when dry, like light wood, but less brittle. Kneaded with Indiarubber solution and glue, it becomes like leather, and can be used in several varieties of repairs. Rolled into sheets, this composition makes very good and cheap artificial leather for hangings. To manufacture these, spread the composition with a broad brush or dabber on a slate or marble table, and when rather dry pass over it a wooden roller. Some practice is needed not to roll it when too soft. If intaglio patterns are cut in the roller, the sheets will give them in relief. It is worth noting here that a great many pieces of old hangings sold as leather are really only made of _papier-mâché_, or _carton-cuir_, and glue. These hangings, whether of leather or counterfeited, can be often bought in a damaged condition very cheaply, and can be easily restored with this composition, to great profit. When mixed with white lead, or oil paint and glue, soft paper becomes harder and firmer, and under pressure is as hard and heavy as any wood. White paper with holly wood or white larch or lime-tree wood in powder, and white gelatine--better if bone or ivory dust be added, with a little Naples yellow (oil)--forms a beautiful cement.

It will be seen by what I have written that cavities, holes, cracks, and defects in most substances, including wood and leather, can be perfectly remedied with paper in combination with glue, gum, or other substances; and as it is always to be obtained, a knowledge of its nature and applications cannot fail to be of value to all menders and restorers.

_Papier-mâché_, like all substantial or putty-like cements, involves moulding or casting. This subject is exhaustively treated in the _Vollständige Anleitung zum Formen und Giessen_, by Eduard Uhlenhuth; Vienna, A. Hartleben, price 3s. On the subject of paper consult the _Handbuch der praktischen Papier-Fabrikation_, by Dr. Stanislaus Mierzinski, three volumes, which is not only the latest, but by far the most comprehensive, work on the subject with which I am acquainted. And here I may observe in this connection that if my references have been chiefly to German works, it is because, in the minor technical applications of chemistry to the arts, and in preparing intelligible practical treatises on such subjects, the Germans have been, especially of late, by far the first nation in Europe.

I may mention that since writing the foregoing passages I purchased, for a mere trifle, in Florence two carved heads of the fourteenth century in walnut wood. They had suffered very much from time and wanton abuse, their noses having been hacked off. I made a mixture of soft paper-paste and gum-arabic, working the two thoroughly in together with a knife-blade till the composition was as soft as butter. This thorough maceration is essential to produce a durable body. With this I filled up the holes, made new noses, and painted the whole with Vandyke brown, or brown-black. In a few minutes the restoration was complete, and the heads which had cost one franc each are now worth at least thirty francs. I should say that the portions restored are as hard as the original wood.

It is not always an easy matter to reduce paper to a perfectly soft paste, such as is called in French _papier-pourri_. A small quantity can be mashed with a knife-blade and flour-paste or gum. A large quantity is prepared as follows:--

Take clippings of paper and leave them a long time in water, which must be occasionally changed. When quite dissolved or soft, bray the paper in a mortar, and finally boil in very hot water. To give it consistency, add flour-paste or gum. This makes a very fine cement, which will receive the most delicate impression. It is invaluable for all kinds of dry mending.

As I have shown, it can be applied to make or mend defective leaves of books, to fill up worm-holes in leaves, to repair drawings and pictures on wood or canvas, and when mixed with any gum which sets hard, to restore, add to, fill, or imitate woodwork. Under pressure and combined with different powders it becomes as hard as ebony and fire-proof. Its extraordinary value and general utility are as yet very far from being much known.

MENDING STONE-WORK

MOSAICS--CERESA-WORK--PORCELAIN OR CROCKERY MOSAIC

Mending or repairing _stone_, involving its imitations, is a widely extended branch of technical science, and one which has of late years called forth much invention. The most widely spread and ancient means of uniting and repairing this material is mortar, or the mixture of burned and then slacked lime with water. Lime is made most commonly from limestone or marble. It improves in quality when carbonate of lime in organic formation, such as sea-shells, is used; and there are degrees of excellence in these, from common oyster-shells to others of a finer kind, such as those with which the brilliantly white and hard _chunam_ of India is made. In certain places mortar, when well made, becomes with age as hard as flint. In American towns, where anthracite coal is burned, it rots away in chimneys under the influence of sulphurous acid with great rapidity. In the Pacific Islands, where lime is made from delicate small sea-shells or coral, and mortar is like a paint or enamel, a missionary has recorded that, when he taught the natives how to make it, they whitewashed everything, even to the children, who thus became white people.

The misapplied word _mastic_, which suggests a gum, refers to certain modifications of mortar into which _oil_ enters; also the oxides of lead or zinc. “Oil forms with these an insoluble soap, which includes or binds the other materials, forming, after one month’s drying, a very hard substance,” which some say is as hard as stone, but which depends entirely on the quality and combination; for I have seen so-called _mastic_ applied to coating cheaply built houses, which cracked or crumbled away like mere plaster of Paris.

To thoroughly amalgamate mastics, it is usual to put their ingredients into casks which are two-thirds filled, and then revolved by machinery. The oil is then added. At least two days are required for the process. The following recipes for mastics are among the best, having been approved by LEHNER. It may here be remarked, once for all, not only as regards mastics, but all recipes in this work, that unless the materials indicated are of the very best quality, and the processes be most thoroughly carried out, the experimenter cannot expect complete success. More than this, the experimenter must not be satisfied with a single trial. If every recipe could be at once executed by every cook, we should find the most exquisite cookery on every table in Europe. I once published the correct recipe for making objects of a peculiar kind of _papier-mâché_ hardened. It was very easy to make. I had seen specimens of the ware, and I received the recipe from the inventor. Moreover, a great deal of money had been made by it. However, soon after I had published it I received an indignant letter from the head of a large manufacturing house, stating that they had tried my recipe and utterly failed!

FRENCH MASTIC:--

Quartz or flint sand, parts 300 Powdered quicklime, ” 100 Litharge, ” 50 Linseed-oil, ” 35

PAGET’S MASTIC:--

Flint sand 315 Washed chalk 105 White lead 25 Minium 10 Sugar of lead in solution 45 Linseed-oil 35

The paste or “dough” thus formed should be ground with horizontal rollers in a mill, such as is used for chocolate, until all the ingredients are _very_ thoroughly amalgamated.

A VERY GOOD CEMENT FOR MENDING, especially where the objects are exposed to water, whether they be of stone or earthenware, is made as follows:--

Powdered glass 40 Washed litharge 40 Linseed-oil varnish 20

The powdered glass is prepared by heating glass red-hot, casting it into water, grinding and sifting it. This powder is saturated with the linseed-oil varnish, and heated in a kettle. This cement sets hard in three days. LEHNER observes that glass-powder serves in such recipes to resist the action of acids, &c., since it forms in combination on the surface a glaze of great hardness; that is, the glass and lead form a chemical combination. Pulverised calcined glass therefore acts not as an “indifferent” but as a chemical ingredient.

CASEINE, or Cheese, forms the basis of several recipes for mending stone, as when there are holes in a block or the mortar has given way. To prepare it for use (LEHNER), we let milk stand in a cool place, skimming away with the utmost care all the cream. Place this on a filter, and pour on it rain-water till it is purified from every trace of lactic acid; then tie it in a cloth, boil it in water, and spread it on blotting-paper in a warm place, when it will be a horn-like substance. This will keep for a long time. To prepare it for use, rub it in a saucer with water.

TO MEND STONE make the following:--

Caseine 12 Slacked lime 50 Fine sand 50

Another recipe:--

Boil new cheese in water till it draws out in threads, stirring in slacked lime and sifted wood-ashes in the following proportions:--

Cheese 100 Water 200 Slacked lime 25 Wood-ashes 20

This may also be used to close cavities in trees or in wood.

A CHEESE CEMENT FOR STONE, and for many other purposes, is made as follows. It may be kept for a long time, and is very durable (LEHNER):--

Caseine 200 Calcined lime 40 Camphor 1

This must be closely incorporated and kept well corked. When it is to be used mix it with water, and apply at once.

The following cement was used by the Romans especially in setting mosaics. It becomes as hard as marble, and sets with great rapidity:--To one quart of milk add the white of five eggs, and stir in powdered quicklime till a paste is formed. This composition may be used to repair or make _scagliola_, which is fragments of marble or stone embedded in a hard mass. When it sets, polish the surface with rasps, and rub down with a rough stone, and finally polish with marble dust, and then emery or tripoli. Beautiful slabs for tables, columns, floors, and walls can thus be made. It is valuable for repairing.

CERESA is allied to this. We make a basis of this or any other cement which will _hold firmly_, and press into the surface powdered glass, which may be fine or of any degree of coarseness. Coarse grains shine most brilliantly; fine powder is best adapted to delicate shading. The effect is best when mosaic stones and gold cubes are sparingly introduced. To make the gold cubes, take two small panes of window glass, cover one side of each with varnish or mastic cement, lay between them gold-leaf, and join them. Very beautiful pictures can be made in this manner. Nor is it at all necessary that they should be finely executed for ordinary decoration. All that is needed for this beautiful and little-known art is the cement, a quantity of glass or stone of different colours, and a mortar and pestle. The mosaic cubes, with those of gold, can be bought in London.

Allied to this is an art which I believe I can claim to have invented. It consists of breaking waste chinaware, crockery, or fictile ware into small squares or triangles, and setting them as mosaic in cement. The advantage of it is the cheapness of the material, and the infinite number of shades of colour which can be selected for it. Its disadvantage is, that it will not wear as a pavement, but it is perfectly adapted to walls.

A STRONG, COARSE CEMENT FOR BRICK OR STONE WORK in building is made as follows:--

Slacked lime 40 Brick-dust 10 Iron filings 10 Ox-blood 8 Water 8

The blood is stirred as it comes from the slaughtered beast with a broom for ten minutes to break the fibre. It should then be mixed with the water and kneaded with the powder. Glue may be substituted for the blood. This cement, if properly made, sets very hard and adhesively.

FOR TILES, BRICKS, OR COMPOSITION:--

Slacked lime 100 Sifted stone-coal ashes 50 Stirred ox-blood 15

It may be observed that many of the cheaper cements can be employed to form large bricks by combination with broken stone or rubble, gravel, pebbles, brickbats, &c. Another method, called CONCRETE, is to make cases of boards, and to form a solid wall by pouring in the mixture, or ramming it down, according to its hardness. Thus a house is made entirely in one piece; but its excellence depends entirely on the quality of the cement employed, and on the care taken in building. Simple lime mortar, if not of a superior quality, hastily formed, as I have seen, is very apt to crack and break off. Where hydraulic cement is cheap and good, houses can be built as firm as granite. A good and strong cement of this kind can be made as follows:--

Burned lime 10 Caseine 12 Hydraulic cement 30

The proportions may be very much varied in such cements according to their price, but generally with a satisfactory result.

Fractures or discolorations in marble, as in statuary, are so perfectly repaired in Florence that the juncture is not perceptible. Even dark spots are drilled out. The process is to drill a round concave hole, and cut the piece to be inserted so as to exactly fit as a convex plug. It is then fastened in with transparent mastic or other clear cement. It will be seen, on due consideration, that this is extremely ingenious, because by it alone can a perfectly tight fit be secured. By turning the plug in the hollow it speedily grinds itself into an accurate plug; so when the cement is applied it can be reduced to a minimum--in fact, by this means the line of junction is reduced to its finest limit.

Where a very strong cement is needed for stone-work, it can be prepared by mixing a fine cement powder--_e.g._, Portland cement--with liquid silicate of soda. As it dries almost at once, it must be promptly applied. It is particularly well adapted for building under water, since it then becomes extremely hard. Before applying it smear the stone with pure silicate.

The following is highly commended by LEHNER:--

Mending statues of gypsum or plaster of Paris is allied to stone-work. The broken edges are washed with water till no more is absorbed and the surface remains wet. Then stir fresh calcined white plaster of Paris with much water to a thin paste, and continue to stir this till it is cold. Then rapidly paint this paste on the broken edges, continuing to press the two together till they set hard.

It is, says LEHNER, a peculiarity of gypsum that when mixed with _alum_ dissolved in water it takes a much longer time to harden, but is very much harder in the end. Thus, if we let the powdered gypsum lie for twenty-four hours in alum-water, dry it, and then calcine it again, the powder when mixed with water sets to a stone as hard as marble.

Plaster of Paris and alum, combined with the fine powder of calcined glass, form a very hard and durable cement, of very general utility in all mending of stone-work.

For an exhaustive work on the subject of not only mending stone-work, but also of making artificial stone and many cements, as well as combining and adapting to use paper, cellulose, sawdust and shavings, gypsum, chalk, glue, &c., including not only ancient but also the most recent recipes, consult _Die Fabrikation künstlicher plastischer Massen_, by Johannes Hofer; Leipzig, A. Hartleben, price 4s.

REPAIRING IVORY

Works of art in carved ivory or bone are very valuable when perfect, yet when broken or defective they may very often be purchased for a trifle. Yet the process of mending them or restoring the missing portions is not difficult.

The first thing to consider is the colour. When old ivory has only acquired a delicate hue, as of Naples yellow, this adds to its attractiveness; nor are the brownish shadows and marks which gather in the angles of the reliefs repulsive. These may be left untouched, and even imitated. But a great deal of old ivory becomes of blackish bistre, or of a dirty, spotted brown or neutral tint, which has nothing in common with artistic effect, and suggests, like old slums in cities, more that is repulsive than picturesque. To clean such pieces, dissolve rock-alum in rain-water till it is white or forms a full saturation. Boil this, and keep the ivory in the boiling solution for about an hour, taking it out from time to time and cleaning it with a soft brush. Then let it dry in a damp linen or muslin rag; it will then be cleaned.