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Papier-Mache

sheets are closely pasted together at all points.

After this the mould is taken to the drying chamber, where it is exposed to a temperature of about 120°. When quite dry, which it takes several hours to accomplish, it is carried back to the pasting-room, and another sheet is laid on, with another coat of paste, after which it is returned to the drying chamber; and the same operation is repeated over and over again, until a sufficient thickness is attained, which, for superior articles, such as are manufactured at these works, requires from 30 to 40 sheets of paper, and of course as many coats of paste between. The shell is then removed from the mould, and planed to shape with a carpenter's plane, after which it is dipped in linseed-oil and spirits of tar to harden it; this changes the color from gray to a dingy yellowishbrown tint. The article is then stoved, and 7 or 8 coats of varnish are laid on (with a stoving after each), which are cleared off each time, any equalities of surface being finally removed with pumicestone. The number of drying processes the articles have to go through consume so much time, that it takes 3 or 4 weeks to fit them for ornamentation, which is applied in bronze-powder, gold, or color, and, for many articles, also in mother-ofpearl. The ornamentation of these articles is sometimes effected in the highest style of the painter's art.

The gold-leaf is laid on with a solution of isinglass in water, the design then pencilled on with asphaltum, the superfluous gold removed with a dossil of cotton dipped in water, which leaves intact the parts touched with asphaltum, and the latter finally removed with essence of turpentine.

After the application of every coat of color or varnish, the object so colored or varnished is dried in an oven or chamber, called a stove, and heated by flues to as high a temperature as can safely be employed without injuring the articles, or causing the varnish to blister.

For black grounds, drop ivory-black mixed with dark-colored anime varnish is used; for colored grounds, the ordinary painters' colors, ground with linseed-oil or turpentine, and mixed with anime varnish.

The colors are protected against atmospheric influences, and made to shine with greater brilliancy, by 2 or 3 coats of copal or anime varnish. Superior articles receive as many as 5 or 6 coats of varnish, and are finally polished.

The ornamentation of all such articles as come under the head of toilet wares is effected by the ordinary mode of painting with the camel's-hair pencil, or some fitting substitute; where imitation of woods or marble is intended, the ordinary grainers' tools are used. Many patterns are produced upon the various articles by "transfer printing." Designs in mother-of-pearl are laid on with black varnish; the article is then varnished all over, dried, then rubbed down over the design with pumice-stone; another coat of varnish is then laid on, dried, and the part covering the design again rubbed off with pumice-stone; and thus several coats are laid on, until all the surface is level with that of the design. Ornamental lines, writing, etc., are laid on with color. The inlay- | ing with mother-of-pearl is a laborious business, owing to the small size of the pieces at the artist's disposal, and the necessity of attending to a proper distribution and fitting of lights and shades.

On a Black Varnish for Zinc.

M. Bettger describes a process for covering zinc with a chemical, adherent, velvet-black varnish. Dissolve 2 parts by weight of nitrate of copper and 3 parts of crystallized chloride in 64 parts of distilled water; add 8 parts of hydrochloric acid of 1.10 density. Into this liquid plunge the zinc, previously scoured with fine sand; then wash the metal with water, and dry it rapidly.

Protection of Iron and Steel.

Moderately-heated benzine dissolves half its weight of wax; and if this solution be carefully applied to the tool with a brush, the evaporation leaves a very adhesive and permanent coating of wax, which will preserve the metal even from the action of acid vapors.

Varnish used for Indian Shields.

Shields made in Silhet, in Bengal, are noted throughout India, for the lustre and durability of the black varnish with which they are covered.

Silhet shields constitute, therefore, no inconsiderable article of traffic, being in request among natives who carry arms, and retain the ancient predilection for the scimitar and buckler. The varnish is composed of the expressed juice of the marking-nut, Semecarpus anacardium, and that of another kindred fruit, Holigarna longifolia. tains between its integuments numerous cells, The shell of the Semecarpus anacardium confilled with a black, acrid, resinous juice, which likewise is found, though less abundantly, in the wood of the tree. It is commonly employed as an indelible ink, to mark all sorts of cotton cloth. The color is fixed with quicklime. The cortical part of the fruit of Holigarna longifolia likewise contains between its laminæ numerous cells, filled with a black, thick, acrid fluid. The natives of nish targets.

Malabar extract by incision, with which they var- To prepare the varnish according tc the method practised in Silhet, the nuts of the Semecarpus anacardium, and the berries of the Holigarna longifolia, having been steeped for a month in clear water, are cut transversely, and pressed in a mill. The expressed juice of each is kept for several months, taking off the scum from time to time. Afterwards the liquor is decanted, and two parts of the one are added to one part of the other, to be used as varnish. Other proportions of ingredients are sometimes employed, but in all the resinous juice of the Semecarpus predominates.

The varnish is laid on like paint, and when dry is polished by rubbing it with an agate or smooth pebble. This varnish also prevents destruction of wood. etc. by the white ant.

To Varnish Silver Leaf like Gold.

Fix the leaf on the subject, similar to gold leaf, by the interposition of proper glutinous matters; spread the varnish upon the piece with a pencil.

When the first coat is dry wash the piece again and again with the varnish till the color appears sufficiently deep. What is called gilt-leather, and many picture-frames, have no other than this gilding; washing them with a little rectified spirit of wine affords a proof of this, the spirit dissolving the varnish, and leaving the silver-leaf of its own whiteness. For plain frames thick tin-foil may be used instead of silver. The tin-leaf, fixed on the piece with glue, is to be burnished, then polished with emery and a fine linen cloth, and afterwards with putty applied in the same manner; being then lacquered over with varnish 5 or 6 times, it looks very nearly like burnished gold.

The same varnish, made with a less proportion of coloring materials, is applied also on works of brass, both for heightening the color of the metal to a resemblance with that of gold, and for preserving it from being tarnished by the air.. To Recover Varnish.

Clear off the filth with a lye made of potash, and the ashes of the lees of wine; then take 48 oz. of potash and 16 of the above-mentioned ashes, and put them into 6 qts. of water, and this completes the lye.

To Polish Varnish.

This is effected with pumice-stone and tripoli earth. The pumice-stone must be reduced to an impalpable powder, and put upon a piece of serge moistened with water: with this rub lightly and equally the varnish substance. The tripoli must also be reduced to a very fine powder, and put upon a clean woollen cloth, moistened with oliveoil, with which the polishing is to be performed. The varnish is then to be wiped off with soft linen, and when quite dry cleaned with starch or Spanish white, and rubbed with the palm of the hand.

Process for giving various Objects a Pearly Lustre.

To produce the iridescence of mother-of-pearl on stone, glass, metal, resin, paper, silk, leather, etc., Reinsch adopts the following process: 2 parts of solution of copal, 2 parts of that of sandarac, and 4 parts of solution of Damara resin (equal parts of resin and absolute alcohol) are mixed with half their volume of oil of bergamot or rosemary. This mixture is to be evaporated to the thickness of castor-oil. If this varnish be then drawn, by means of a feather or brush, over the surface of some water, it will form a beautiful iri. descent pellicle. This film is now to be applied to the objects which are to be rendered iridescent.

The vessel in which the water is contained, on which the pellicle has been produced, must therefore be as large as or larger than these objects. The water should have about 5 per cent. of pure solution of lime added to it; its temperature should be kept at about 72°. The objects are dried in the air.

To Prevent the Formation of Fungi in Timber.

The following paint has been found successful:

Flour of sulphur, 3088 grs.; common linseed-oil, 2084 grs.; refined oil of manganese, 463 grs.

Prevention of Rotting of Wood.

Take 50 parts of rosin, 40 of finely powdered chalk, 300 parts or less of fine, white, sharp sand, 4 parts of linseed-oil, 1 part of native red oxide of copper, and 1 part of sulphuric acid. First heat the rosin, chalk, sand and oil, in an iron boiler; then add the oxide, and, with care, the acid. Stir the composition carefully, and apply while hot. If too thick, add more oil. This coating, when cold and dry, forms a varnish hard as stone.

Hydraulic Mortar.