oz. of alum should be added to each quantity of water before it is used. Having thus sufficiently freed the latter from the salts, drain off the water through a filter, covered with a worn linen cloth. When it has been drained to a proper dryness, let it be dropped through a proper funnel on clean boards, and the drops will become small cones or pyramids, in which form the lake must be dried, and the preparation is completed.

Another Method.

sulphate alumina, or a decoction of Brazil-wood with sulphate alumina; the color may be varied by the addition of carbonate potash.

To make Purple

A decoction of Brazil-wood and logwood affords, with carbonate of potash, a permanent purple. To make Orange Lake.

Boil 4 oz. of the best anatto and 1 lb. of pearlash, an hour, in 1 gall. of water, and strain the Boil 2 oz. of cochineal in 1 pt. of water; filter solution through paper. Mix gradually with this the solution through paper, and add 2 oz. of pearl-1 lbs. of alum, in another gallon of water, desist

ash dissolved inpint of warm water and fil. tered through paper. Make a solution of cuttlebone, as in the former process, and to 1 pt. of it add 2 oz. of alum dissolved in pt. of water. Putthis mixture gradually to the cochineal and pearl

ash as long as any ebullition arises, and proceed

as above.

A beautiful lake may be prepared from Brazilwood, by boiling 3 lbs. of it for an hour in a solution of 3 lbs. of common salt in 3 galls. of water, and filtering the hot fluid through paper; add to this a solution of 5 lbs. of alum in 3 galls. of water. Dissolve 3 lbs. of the best pearlash in 14 galls. of water, and purify it by filtering; put this gradually to the other till the whole of the color appears to be precipitated and the fluid is left clear and colorless. But if any appearance of purple be seen, add a fresh quantity of the solution of alum by degrees, till a scarlet hue is produced. Then pursue the directions given in the first process with regard to the sediment. If lb. of seed-lac be added to the solution of pearlash, and dissolved in it before its purification by the filter, and 2 lbs. of the wood and a proportional quantity of common salt and water be used in the colored solution, a lake will be produced that will stand well in oil or water; but it is not so transparent in oil as without the seed-lac. The lake with Brazilwood may be also made by adding oz. of anatto to each pound of the wood; but the anatto must be dissolved in the solution of pearlash.

After the operation, the dryers of plaster, or the bricks, which have extracted the moisture from the precipitate, are exposed to the sun, that they may be fitted for another operation.

To make Prussian Blue.

Treat the sediment in the manner already directed ing when no ebullition attends the commixture. for other kinds of lake, and dry it in square bits or lozenges.

To make a Yellow Lake.

pt. of water, and 1 oz. of salt of tartar; put all into

Take 1 lb. of turmeric-root, in fine powder, 3

a glazed earthen vessel, and boil them together over a clear gentle fire, till the water appears highly impregnated and stains a paper to a beautiful yellow. Filter this liquor, and gradually add to it a strong solution of alum, in water, till the yellow matter is all curdled and precipitated. After this, pour the whole into a filter of paper, and the water will run off, and leave the yellow matter behind. Wash it with fresh water till the water comes off insipid, and then is obtained the beautiful yellow called lacque of turmeric.

In this manner make a lake of any of the substances that are of a strong texture, as madder, logwood, etc., but it will not succeed in the more tender species, as the flowers of roses, violets, etc., as it destroys the nice arrangement of parts in those subjects on which the color depends.

To make another Yellow Lake.

Make a lye of potash and lime sufficiently strong; in this boil, gently, fresh broom-flowers till they are white; then take out the flowers, and put the lye to boil in earthen vessels over the fire; add as much alum as the liquor will dissolve; then empty this lye into a vessel of clean water, and it will give a yellow color at the bottom. Settle, and decant off the clear liquor. Wash this powder, which is found at the bottom, with more water, till all the salts of the lye are washed off; then separate the yellow matter, and dry it in the shade, To Make a Yellow.

Gum guttæ and terra merita give very beautiful yellows, and readily communicate their color to copal varnish made with turpentine. Aloes give

Dissolve sulphate of iron (copperas, green vitriol) in water; boil the solution. Add nitric acid until red fumes cease to come off, and enough sulphuric acid to render the liquor clear. This is the persulphate of iron. To this add a solution of ferrocyanide of potassium (yellow prussiate Chloride of lead tinges vitreous matters of a yelof potash), as long as any precipitate is produced. Wash this precipitate thoroughly with water acid-low color. Hence the beautiful glazing given to ulated with sulphuric acid, and dry in a warm place.

Soluble Prussian Blue.

Add ferrocyanide of potassium to a solution freshly made of green vitriol in water. The white precipitate which falls, becomes blue on exposure to the air, and is soluble in water.

Chrome Red.

Melt saltpetre in a crucible heated to dull redness, and throw in gradually chrome yellow until no more red fumes arise. Allow the mixture to settle; pour off the liquid portion, and wash rapidly the sediment. The liquid portion contains chromate of potash, and may be used to make chrome yellow. To make Blue.

a varied and orange tint.

Queen's ware. It is composed of 80 lbs. of chloride of lead, and 20 lbs. of flints ground together very fine, and mixed with water till the whole becomes as thick as cream. The vessels to be

glazed are dipped in the glaze and suffered to dry.

To make Chinese Yellow.

The acacia, an Egyptian thorn, is a species of mimosa, from which the Chinese make that yellow which bears washing in their silks and stuffs, and appears with so much elegance in their painting on paper. The flowers are gathered before they are fully opened, and put into an earthen vessel over a gentle heat, being stirred continually until they are nearly dry, and of a yellow color: then to lb. of the flowers a sufficient quantity of rain-water is added, to hold the flowers incorporated together. It is then to be boiled until it becomes thick, when it must be strained. To the liquor is added oz. of common alum, and 1 oz. Cochineal boiled with bitartrate of potash and of calcined oyster-shells, reduced to a fine powder.

A diluted solution of sulphate of indigo.

To make Pink.

All these are mixed together into a mass. An addition of a proportion of the ripe seeds to the flowers renders the colors somewhat deeper. For making the deepest yellow add a small quantity of Brazil-wood.

Tunic White,

Largely used as a substitute for white lead, may be made by burning zinc, or by precipitating from a solution by caustic alkali. It is the oxide of the metal, and is not blackened by sulphuretted hydrogen.

To make a Pearl White.

Pour some distilled water into a solution of nitrate of bismuth as long as precipitation takes place; filter the solution, and wash the precipitate with distilled water as it lies on the filter. When properly dried, by a gentle heat, this powder is what is generally termed pearl white.

Chrome Green.

solution of gelatine; to this mixture is then added 10 or 11 per cent. of protochloride of tin, and lastly an excess of caustic potash soda. The precipitate is then washed and dried, whereupon it assumes a green color, with a tint of blue.

The "Tin-copper Green" is a stannate of copper, and possesses a color which Gentele states is not inferior to any of the greens free from arsenic. The cheapest way of making this is to hes 59 parts of tin in a Hessian crucible, with 100 parts of nitrate of soda, and dissolve the mass, when cold, in a caustic alkali. When clear, this solation is diluted with water, and a cold solution of sulphate of copper is added. A reddish yellow precipitate falls, which, on being washed and dried, becomes a beautiful green.

Titanium Green was first prepared by Elsner in 1846. It is made in the following way: Iserin (titaniferous iron) is fused in a Hessian crucible When cold, the fused mass is treated with hydrowith 12 times its weight of sulphate of potash.

Mix bichromate of potash with half its weight of muriate of ammonia; heat the mixture to red-chloric acid, heated to 50° C. and filtered hot; ness, and wash the mass with plenty of boiling water. Dry the residue thoroughly. It is a sesquioxide of chromium, and is the basis of the green ink used in bank-note printing. Another. Mix chrome yellow and Prussian

blue.

Guignet's Chrome Green.

the filtrate is then evaporated until a drop placed on a glass plate solidifies. It is then allowed to cool, and when cold a concentrated solution of sal stirred and then filtered. The titanic acid which ammoniac is poured over the mass, which is well remains behind is digested at 50° or 70° with dilute hydrochloric acid, and the acid solution, after Mix 3 parts of boracic acid and 1 part of bichro- the addition of some solution of prussiate of potmate of potassa, heat to about redness. Oxygen ash, quickly heated to boiling. A green precipigas and water are given off. The resulting salt tate falls, which must be washed with water aciduwhen thrown into water is decomposed. The pre-lated with hydrochloric acid, and then dried under eipitate is collected and washed. This is a remark- 100° C. Titanium green then forms a beautiful ably fine color, solid and brilliant even by arti- dark green powder. ficial light. To make Scheele's Green.

This is obtained from the solution of a precipitate of copper in tartar and water, which, by evaporation, yields a transparent cupreous tartar, which is similar to the superfine Brunswick green.

Schweinfürth or Emerald Green Color. Dissolve in a small quantity of hot water, 6 parts of sulphate of copper; in another part, boil 6 parts of oxide of arsenic with 8 parts of potash, until it throws out no more carbonic acid; mix by degrees this hot solution with the first, agitating continually until the effervescence has entirely ceased; these then form a precipitate of a dirty greenish yellow, very abundant; add to it about 3 parts of acetic acid, or such a quantity that there may be a slight excess perceptible to the smell after the mixture; by degrees the precipitate diminishes the bulk, and in a few hours there deposes spontaneously at the bottom of the liquor, entirely discolored, a powder of a contexture slightly crystalline, and of a very beautiful green; afterwards the floating liquor is separated.

Green Colors free from Arsenic. Some green colors free from the objections which apply to the arsenical greens, are described by Elsner. The first, called "Elsner Green," is made by adding to a solution of sulphate of copper a decoction of fustic, previously clarified by a

A Green Color which may be employed in Confec tionary.

Infuse for 24 hours 0.32 grammes of saffron in 7 grammes of distilled water; take 0.26 grammes of carmine of indigo and infuse in 15.6 grammes of distilled water. On mixing the two liquids a beautiful green color is obtained, which is harmless. Ten parts will color 1000 parts of sugar. It may be preserved for a long time by evaporatirg the liquid to dryness, or making it into a syrup.

To mix the Mineral Substances in Linseed Oil. Take 1 lb. of the genuine mineral green, prepared and well powdered, 1 lb. of the precipitate of copper, 1 lbs. of refiners' blue verditer, 3 lbs. of white lead, dry powdered, 3 oz. of sugar of lead, powdered fine. Mix the whole of these ingredients in linseed oil, and grind them in a levigating mill, passing it through until quite fine; it will thereby produce a bright mineral pea-green paint, preserve a blue tint, and keep any length of time in any climate without injury, by putting oil or wa

ter over it.

take 1 lb. of the green color paint, with 1 gill of To use this color for house or ship painting, pale boiled oil; mix them well together, and this will produce a strong pea-green paint; the tint quantity of white lead ground in linseed oil. may be varied at pleasure by adding a further This color will stand the weather and resist salt water; it may also be used for flatting rooms, by adding 3 lbs. of white lead ground in half linseed to be mixed up in turpentine spirits, fit for use. It oil and half turpentine, to 1 lb. of the green, then may also be used for painting Venetian windowblinds, by adding to 1 lb. of the green paint 10 oz. of white lead, ground in turpentine, then to be mixed up in turpentine varnish for use. In all the aforesaid preparations it will retain a blue tint, which is very desirable. When used for blinds, a small quantity of Dutch pink may be

put to the white lead if the color is required of a Compound for Receiving the Colors used in Enyellow cast.

To Imitate Flesh-color.

caustic Painting.

Dissolve 9 oz. of gum arabic in 1 pt. of water, add 14 oz. of finely powdered mastic and 10 oz. of white wax, cut in small pieces, and, whilst hot, add by degrees 2 pts. of cold spring-water; then

Mix a little white and yellow together, then add a little more red than yellow. These form an excellent imitation of the complexion. A White for Painters, which may be Preserved strain the composition. Forever.

Another Method.

Put into a pan 3 qts. of linseed oil, with an equal Mix 24 oz. of mastic with gum-water, leaving quantity of brandy and 4 qts. of the best double-out the wax, and when sufficiently beaten and disdistilled vinegar, 3 doz. of whole new-laid eggs, 4 solved over the fire, add by degrees 14 pts. of cold lbs. of mutton suet, chopped small; cover all with water, and strain. a lead plate and lute it well; lay this pan in the cellar for 3 weeks, then take skilfully the white off, and dry it. The dose of this composition is 6 oz. of white to 1 of bismuth.

To Clean Pictures.

Take the picture out of the frame, lay a coarse towel on it for 10 or 14 days; keep continually

wetting it until it has drawn out all the filthiness from the picture; pass some linseed oil, which has been a long time seasoned in the sun, over it, to purify it, and the picture will become as lively on the surface as new.

Another Method.

Put into 2 qts. of the oldest lye lb. of Genoa soap, rasped very fine, with about a pint of spirit of wine, and boil all together; then strain it through a cloth, and let it cool. With a brush dipped in the composition rub the picture all over, and let it dry; repeat this process and let it dry again; then dip a little cotton in oil of nut, and pass it over its surface. When perfectly dry, rub it well over with a warm cloth, and it will appear of a beautiful freshness.

Or, dissolve 9 oz. of gum arabic in 1 pts. of water; then add 1 lb. of white wax. Boil them over a slow fire, pour them into a cold vessel, and beat them well together. When this is mixed with the colors, it will require more water than the others. This is used in painting, the colors being mixed with these compositions as with oil, adding water if necessary. When the painting is finished, melt some white wax, and with a hard brush varnish the painting, and, when cold, rub it to make it entirely smooth.

Grecian Method of Painting on Wax. Take 1 oz. of white wax and 1 oz. of gum mastic, in drops, made into powder; put the wax into a glazed pan over a slow fire, and when melted add the mastic; then stir the same until they are both incorporated. Next throw the paste into water, and when hard take it out, wipe it dry, and beat it in a mortar; when dry pound it in a linen cloth till it is reduced to a fine powder. Make some strong gum-water, and when painting take a little of the powder, some color, and mix them all with the gum-water. Light colors require but a small quantity of the powder, but more must be put in proportion to the darkness of the colors, In paintings, where the white has become black-and to black there should be almost as much of ened by sulphuretted hydrogen, the application the powder as of color. of Thenard's oxygenated water will instantly restore it. Probably a solution of permanganate of potassa would have the same effect. (See CONDY'S SOLUTION).

To Restore Discolored White.

To Restore Paintings.

Having mixed the colors, paint with water, as is practised in painting with water colors, a ground on the wood being first painted of some proper color, prepared as described for the picture. When the painting is quite dry, with a hard Prof. Pettenkoffer has shown that the change brush, passing it one way, varnish it with white which takes place in old paintings, is the discon-wax, which is melted over a slow fire till the pictinuance of molecular cohesion, which, beginning ture is varnished. Take care the wax does not on the surface in small fissures, penetrates to the boil. Afterwards hold the picture before a fire, very foundation. His process is to expose the pic-near enough to melt the wax, but not to run, and ture in a tight box to the vapor of alcohol, ether, benzine, turpentine, or other similar solvent. The process has been successfully tried in several instances.

when the varnish is entirely cold and hard, rub it gently with a linen cloth. Should the varnish blister, warm the picture again very slowly, and the bubbles will subside.

VARNISHES.

Solvents for India-Rubber and Gutta Percha. 1. Benzine. There are two bodies sold as benzine or benzole: one obtained by distilling coal or coal-tar-the true benzine-used in making coaltar colors; the other, from petroleum, contains but little true benzine. They may be used instead of turpentine in mixing paints and the true benzine for varnishes. Commercial benzine will not generally do for varnishes; that from petroleum is much the cheaper. Either forms an excellent solvent for india-rubber.

2. Bisulphide of Carbon is an excellent rubber

solvent; acts in the cold; is made by passing the
vapor of sulphur over red-hot charcoal.
3. Chloroform is very good, but costly.
Turpentine acts slowly, and takes long to dry.
India rubber should always be cut into fine strings
or shreds before being submitted to the action of
solvents.

Solvent for Old Paint or Putty.

Caustic soda, applied with a broom or brush made of vegetable matter. It is sold in the shops as concentrated lye.

ides contain a great deal of oxygen, and the oil, by their contact, acquires more of a drying quality. Another.-Take of nut oil, 2 lbs. ; common water, do.; sulphate of zinc, 2 oz.

Mix these matters, and subject them to a slight ebullition, till little water remains Decant the oil, which will pass over with a small quantity of water, and separate the latter by means of a funnel. The oil remains nebulous for some time; after which it becomes clear, and seems to be very little colored.

To give a Drying Quality to Poppy Oil. into 3 lbs. of pure water put 1 oz. of sulphate of zinc (white vitriol), and mix the whole with 2 lbs. of oil of pinks, or poppy oil. Expose this mix-3 ture, in an earthen vessel capable of standing the fire, to a degree of heat sufficient to maintain it in a slight state of ebullition. When one-half or two-thirds of the water has evaporated, pour the whole into a large glass bottle or jar, and leave it at rest till the oil becomes clear. Decant the clearest part by means of a glass funnel, the beak of which is stopped with a piece of cork. When the separation of the oil from the water is effected, remove the cork stopper, and supply its place with the forefinger, which must be applied in such a manner as to suffer the water to escape, and to retain only the oil.

Poppy-oil, when prepared in this manner, becomes, after some weeks, exceedingly limpid and colorless.

To give a Drying Quality to Fat Oils. Take of nut-oil, or linseed-oil, 8 lbs.; white lead, sightly calcined, yellow acetate of lead (sal saturni), also calcined, sulphate of zinc (white vitriol), each 1 oz.; vitreous oxide of lead (litharge), 12 oz.; a head of garlic, or a small onion.

When the dry substances are pulverized, mix them with the garlic and oil, over a fire capable of maintaining the oil in a slight state of ebullition. Continue it till the oil ceases to throw up scum, till it assumes a reddish color, and till the head of garlic becomes brown; a pellicle will then be soon formed on the oil, which indicates that the operation is completed. Take the vessel from the fire, and the pellicle, being precipitated by rest, will carry with it all the unctuous parts which rendered the oil fat. When the oil becomes clear, separate it from the deposit, and put it into widemouthed bottles, where it will completely clarify itself in time, and improve in quality.

Another Method.

of

Take of litharge, 14 oz.; sulphate of zinc, an oz.; linseed or nut-oil, 16 oz. The operation must be conducted as in the preceding case.

The choice of the oil is not a matter of indifference. If it be destined for painting articles exposed to the impression of the external air, or for, delicate painting, nut-oil or poppy-oil. Linseedoil is used for coarse painting, and that sheltered

from the effects of the rain and of the sun.

A little negligence in the management of the fire has often an influence on the color of the oil, to which a drying quality is communicated; in this case it is not proper for delicate painting. This inconvenience may be avoided by tying up the drying matters in a small bag; but the dose of the litharge must then be doubled. The bag must be suspended by a piece of pack thread fastened to a stick, which is made to rest on the edges of the vessel in such a manner as to keep the bag at the distance of an inch from the bottom of the vessel. A pellicle will be formed as in the first operation, but it will be slower in making its appearance.

Another. A drying quality may be communicated to oil by treating, in a heat capable of maintaining a slight ebullition, linseed or nut-oil, to each pound of which is added 3 oz. litharge, reduced to fine powder.

Another.-Take of nut-oil, or linseed-oil, 6 lbs.; common water, 4 lbs. ; sulphate of zinc, 1 oz. ; garlic, 1 head.

Mix these matters in a large iron or copper pan; then place them over the fire, and maintain the mixture in a state of ebullition during the whole day. Boiling water must from time to time be added, to make up for the loss of that by evaporation. The garlic will assume a brown appearance. Take the pan from the fire, and having suffered a deposit to be formed, decant the oil, which will clarify itself in the vessel. By this process the drying oil is rendered somewhat more colored. It is reserved for delicate colors.

Preparation of a Drying Oil for Zinc Paint. In order to avoid the use of oxide of lead in making drying oil for zinc paint, oxide of manganese has been proposed as a substitute. The process to be adopted is as follows:

The manganese is broken into pieces about the size of peas, dried, and the powder separated by means of a sieve. The fragments are then to be introduced into a bag made of iron-wire gauze. This is hung in the oil contained in an iron or copper vessel, and the whole heated gently for 24 or 36 hours. The oil must not be allowed to boil, in which case there is great danger of its running over. When the oil has acquired a reddish color, it is to be poured into an appropriate vessel to clear.

For 100 parts of oil 10 of oxide of manganese may be employed, which will serve for several operations when freshly broken and the dust separated. Experience has shown, that when fresh oxide of manganese is used it is better to introduce it into the oil upon the second day. The process likewise occupies a longer time with the fresh oxide. Very great care is requisite in this operation to prevent accident, and one of the principal points to be observed is that the oil is not overheated. If the boiling should render the oil too thick, this may be remedied by an addition of turpentine after it has thoroughly cooled. On the Manufacture of Drying Linseed Oil without Heat.

When linseed-oil is carefully agitated with vinegar of lead (tribasic acetate of lead), and the mixture allowed to clear by settling, a copious white, cloudy precipitate forms, containing oxide of lead, whilst the raw oil is converted into a drying oil of a pale-straw color, forming an excellent varnish, which, when applied in thin layers, dries perfectly in 24 hours. It contains from 4 to 5 per cent. of oxide of lead in solution. The following proportions appear to be the most advantagecus for its preparation :

In a bottle containing 44 pts. of rain-water, 18 The preparation of floor-cloths, and 'all paint- oz. of neutral acetate of lead are placed, and when ings of large figures or ornaments, in which argil- the solution is complete, 18 oz. of litharge in a laceous colors, such as yellow and red boles, Dutch very fine powder are added; the whole is then alpink, etc. are employed, require this kind of prep- lowed to stand in a moderately warm place, frearation, that the desiccation may not be too slow; quently agitating it to assist the solution of the but painting for which metallic oxides are used, litharge. This solution may be considered as comsuch as preparations of lead, copper, etc., require plete when no more small scales are apparent. The only the doses before indicated, because these ox-deposit of a shining white color (sexbasic acetate

of lead may be separated by filtration. This con- | may be added. The latter liquor is a regulator version of the neutral acetate of lead into vinegar for the consistence in the hands of an artist.

Liquefy the copal in a matrass over a common fire, and then add the linseed oil, or oil of poppies, in a state of ebullition; when these matters are incorporated, take the matrass from the fire, stir the matter till the greatest heat is subsided, and then add the essence of turpentine warm. Strain the whole, while still warm, through a piece of linen, and put the varnish into a wide-mouthed This varnish is a little colored, and by rest it bottle. Time contributes towards its clarification, acquires a transparency which, united to the soand in this manner it acquires a better quality. lidity observed in almost every kind of copal varVarnish for Watch Cases in Imitation of Tortoise-nish, renders it fit to be applied with great succes