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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 coal tar 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.
Caustic soda applied with a broom or brush made of vegetable matter. It is sold in the shops as concentrated lye.
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 mixture, 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.
Take of nut-oil, or linseed-oil, 8 lbs.; white lead, slightly 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.
Take of litharge, 1 1/2 oz.; sulphate of zinc, 3/8 of 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. Linseed-oil 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 packthread 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.
The preparation of floor-cloths, and all paintings of large figures or ornaments, in which argillaceous colors, such as yellow and red boles, Dutch pink, etc. are employed, require this kind of preparation, that the dessication may not be too slow; but painting for which metallic oxides are used, such as preparations of lead, copper, etc., require only the doses before indicated, because these oxides 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, 3 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.
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.
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 principle 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.
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 advantageous for its preparation:
In a bottle containing 4 1/2 pts. of rain-water, 18 oz. of neutral acetate of lead are placed, and when the solution is complete, 18 oz. of litharge in a very fine powder are added; the whole is then allowed to stand in a moderately warm place, frequently agitating it to assist the solution of the litharge. This solution may be considered as complete when no more small scales are apparent. The deposit of a shining white color (sexbasic acetate of lead may be separated by filtration. This conversion of the neutral acetate of lead into vinegar of lead, by means of litharge and water, is effected in about a quarter of an hour, if the mixture be heated to ehullition. When heat is not applied, the process will usually take 3 or 4 days. The solution of vinegar of lead, or tribasic acetate of lead, thus formed, is sufficient for the preparation of 22 lbs. of drying oil. For this purpose the solution is diluted with an equal volume of rain-water, and to it is gradually added, with constant agitation, 22 lbs. of oil, with which 18 oz. of litharge have previously been mixed.
When the points of contact between the lead solution and the oil have been frequently renewed by agitation of the mixture 3 or 4 times a day, and the mixture allowed to settle in a warm place, the limpid straw-colored oil rises to the surface, leaving a copious white deposit. The watery solution, rendered clear by filtration, contains intact all the acetate of lead at first employed, and may be used in the next operation, after the addition to it as before, of 18 oz. of litharge.
By filtration through paper or cotton, the oil may be obtained as limpid as water, and by exposure to the light of the sun it may also be bleached.
Should a drying oil be required absolutely free from lead, it may be obtained by the addition of dilute sulphuric acid to the above, when, on being allowed to stand, a deposit of sulphate of lead will take place, and the clear oil may be obtained free from all trace of lead.
Take 10 lbs. of drying nut-oil, if the paint is destined for external articles, or 10 lbs. of drying linseedoil if for internal; resin, 3 lbs.; turpentine, 6 oz.
Cause the resin to dissolve the oil by means of a gentle heat. When dissolved and incorporated with the oil, add the turpentine; leave the varnish at rest, by which means it will often deposit portions of resin and other impurities; and then preserve it in wide-mouthed bottles. It must be used fresh; when suffered to grow old it abandons some of its resin. If this resinous oil assumes too much consistence, dilute it with a little essence, if intended for articles sheltered from the sun, or with oil of poppies.
Take picked copal, 16 oz.; prepared linseed oil, or oil of poppies, 8 oz.; essence of turpentine, 16 oz.
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 bottle. Time contributes towards its clarification, and in this manner it acquires a better quality.
Take copal of an amber color, 6 oz.; Venice turpentine, 1 1/2 oz.; prepared linseed-oil, 24 oz.; essence of turpentine, 6 oz.
It is customary to place the turpentine over the copal, reduced to small fragments, in the bottom of an earthen or metal vessel, or in a matrass exposed to such a heat as to liquefy the copal; but it is more advantageous to liquefy the latter alone, to add the oil in a state of ebullition, then the turpentine liquefied, and in the last place the essence. If the varnish is too thick, some essence may be added. The latter liquor is a regulator for the consistence in the hands of an artist.
Take copal in powder, 1 oz.; essential oil of lavender, 2 oz.; essence of turpentine, 6 oz.
Put the essential oil of lavender into a matrass of a proper size, placed on a sand-bath heated gently. Add to the oil while very warm, and at several times, the copal powder, and stir the mixture with a stick of white wood rounded at the end. When the copal has entirely disappeared, add at three different times the essence almost in a state of ebullition, and keep continually stirring the mixture. When the solution is completed, the result will be a varnish of a gold-color, exceedingly durable and brilliant.
To obtain this varnish colorless, it will be proper to rectify the essence of the shops, which is often highly colored, and to give it the necessary density by exposure to the sun in bottles closed with cork stoppers, leaving an interval of some inches between the stopper and the surface of the liquid. A few months are thus sufficient to communicate to it the required qualities. Besides, essence of the shops is rarely possessed of that state of consistence without having at the same time a strong amber color.
The varnish resulting from the solution of copal in oil of turpentine, brought to such a state as to produce the maximum of solution, is exceedingly durable and brilliant. It resists the shock of hard bodies much better than the enamel of toys, which often becomes scratched and whitened by the impression of repeated friction; it is susceptible also of a fine polish. It is applied with the greatest success to philosophical instruments, and the paintings with which vessels and other utensils of metal are decorated.
This varnish is destined for articles which require durability, pliableness, and transparency.
Take of pulverized copal, 2 oz.; essential oil of lavender, 6 oz.; camphor, 1/8 oz.; essence of turpentine, a sufficient quantity, according to the consistence required to be given to the varnish.
Put into a phial of thin glass, or into a small matrass, the essential oil of lavender and the camphor, and place the mixture on a moderately open fire, to bring the oil and the camphor to a slight state of ebullition; then add the copal powder in small portions, which must be renewed as they disappear in the liquid. Favor the solution, by continually stirring with a stick of white wood; and when the copal is incorporated with the oil, add the essence of turpentine boiling; but care must be taken to pour in, at first, only a small portion.
This varnish is a little colored, and by rest it acquires a transparency which, united to the solidity observed in almost every kind of copal varnish, renders it fit to be applied with great success in many cases.
Take of amberry copal, 3 oz.; ether, 2 oz.
Reduce the copal to a very fine powder, and introduce it by small portions into the flask which contains the ether; close the flask with a glass or a cork stopper, and having shaken the mixture for an hour, leave it at rest till the next morning. In shaking the flask, if the sides become covered with small undulations, and if the liquor be not exceedingly clear, the solution is not complete. In this case add a little ether, and leave the mixture at rest. The varnish is of a white lemon-color. The largest quantity of copal united to ether may be a fourth, and the least a fifth. The use of copal varnish made with ether seems, by the expense attending it, to be confined to repairing those accidents which frequently happen to the enamel of toys, as it will supply the place of glass to the colored varnishes employed for mending fractures, or to restoring the smooth surface of paintings which have been cracked and shattered.
The great volatility of ether, and in particular its high price, do not allow the application of this varnish to be recommended, but for the purposes here indicated. It has been applied to wood with complete success, and the glazing it produced unites lustre to solidity. In consequence of the too speedy evaporation of the liquid, it often boils under the brush. Its evaporation, however, may be retarded, by spreading over the wood a light stratum of essential oil of rosemary or lavender, or even of turpentine, which may afterwards be removed by a piece of linen rag; what remains is sufficient to retard the evaporation of the ether.
Take of amber or copal of one fusion, 4 oz.; essence of turpentine, drying linseed oil, of each, 10 oz.
Put the whole into a pretty large matrass, and expose it to the heat of a balneum maria, or move it over the surface of an uncovered chafing-dish, but without flame, and at the distance from it of 2 or 3 inches. When the solution is completed, add still a little copal or amber to saturate the liquid, then pour the whole on a filter prepared with cotton, and leave it to clarify by rest. If the varnish is too thick, add a little warm essence to prevent the separation of any of the amber.
This varnish is colored, but far less so than those composed by the usual methods. When spread over white wood, without any preparation, it forms a solid glazing, and communicates a slight tint to the wood.
If it is required to charge this varnish with more copal, or prepared amber, the liquor must be composed of two parts of essence for one of oil.
The properties manifested by these varnishes, and which render them proper for supplying the vitreous and transparent coating of enamel, by a covering equally brilliant, but more solid, and which adheres to vitreous compositions, and to metallic surfaces, admit of their being applied to other purposes besides those here enumerated.
By slight modifications they may be used also for the reparation of opake enamel which has been fractured. These kinds of enamel admit the use of cements colored throughout, or only superficially, by copal varnish charged with coloring parts. On this account they must be attended with less difficulty in the reparation than transparent enamel, because they do not require the same reflection of the light. Compositions of paste, therefore, the different grounds of which may always harmonize with the coloring ground of the pieces to be repaired, and which may be still strengthened by the same tint introduced into the solid varnish, with which the articles are glazed will answer the views of the artist in a wonderful manner.
The base of the cement ought to be pure clay without color, and exceedingly dry. If solidity be required, ceruse is the only substance that can be substituted in its place. Drying oil of pinks will form an excellent excipient, and the consistence of the cement ought to be such that it can be easily extended by a knife or spatula, possessed of a moderate degree of flexibility. This sort of paste soon dries. It has the advantage also of presenting to the colors, applied to it with a brush, a kind of ground which contributes to their solidity. The compound mastic being exceedingly drying, the application of it will be proper in cases where speedy reparation of the damaged articles is required.
In more urgent cases, the paste may be composed with ceruse, and the turpentine copal varnishes, which dry more speedily than oil of pinks; and the colors may then be glazed with the ethereal copal varnish.
The application of the paste will be necessary only in cases when the accident, which has happened to the enamel, leaves too great a vacuity to be filled up by several strata, of colored varnish. But in all cases the varnish ought to be well dried, that it may acquire its full lustre by polishing.
White oxide of lead, ceruse, Spanish white, white clay. Such of these substances as are preferred ought to be carefully dried. Ceruse and clay obstinately retain a great deal of humidity which would oppose their adhesion to drying oil or varnish. The cement then crumbles under the fingers, and does not assume a body.
Another. - On 16 oz. of melted copal, pour 4, 6 or 8 oz. of linseed-oil boiled, and quite free from grease. When well mixed by repeated stirrings, and after they are pretty cool, pour in 16 oz. of the essence of Venice turpentine. Pass the varnish through a cloth. Amber varnish is made the same way.
Lampblack, made of burnt vine-twigs, or black of peachstones. The lampblack must be carefully washed and afterwards dried. Washing carries off a great many of its impurities.
Yellow oxide of lead, of Naples and Montpellier, both reduced to impalpable powder. These yellows are hurt by the contact of iron and steel; in mixing them up, therefore, a horn spatula with a glass mortar and pestle must be employed.
Gum guttae, yellow ochre, or Dutch pink, according to the nature and tone of the color to be imitated.
Indigo, prussiate of iron (Prussian blue), blue verditer, and ultramarine. All these substances must be very much divided.
Verdigris, crystallized verdigris, compound green (a mixture of yellow and blue). The first two require a mixture of white in proper proportions, from a fourth to two-thirds, according to the tint intended to be given. The white used for this purpose is ceruse, or the white oxide of lead, or Spanish white, which is less solid, or white of Moudon.
Red sulphuretted oxide of mercury (cinnabar vermilion), red oxide of lead (minium), different red ochres, or Prussian reds, etc.
Cochineal, carmine, and carminated lakes, with ceruse and boiled oil.
Dragon's blood.
Dragon's blood with a paste composed of flowers of zinc, or, what is still better, a little red vermilion.
Cinnabar, mixed with lampblack, washed very dry, or with the black of burnt vine-twigs; and, to render it mellower, a proper mixture of red, blue, and white.
White and black; white and blue; for example, ceruse and lampblack; ceruse and indigo.
Ceruse, which forms the ground of the paste, mixed with a smell quantity of Cologne earth, as much English red, or carminated lake, which is not so durable, and a particle of Prussian blue.
Melt 4 lbs. of common asphalt, and add 2 pts. of boiled linseed-oil, and 1 gall. of oil of turpentine or coaltar naphtha.
Four ounces india-rubber in fine shavings are dissolved in a covered jar by means of a sand-bath, in 2 lbs. of crude benzole, and then mixed with 4 lbs. of hot linseedoil varnish heated, and filtered. (See CEMENTS).
To 1 qt. of cold linseed-oil poured off from the lees (produced on the addition of unslaked lime, on which the oil has stood 8 or 10 days at the least, in order to communicate a drying quality, or brown umber burnt and powdered which will have the like effect,) add 1/2 oz. of litharge; boil them for 1/2 hour, then add 1/2 oz. of the copal varnish. While the ingredients are on the fire, in a copper vessel, put in 1 oz. of chios turpentine or common resin, and a few drops of neat's-foot oil and stir the whole with a knife; when cool it is ready for use. The neat's-foot oil prevents the varnish from being sticky or adhesive, and may be put into the linseed-oil at the same time with the lime or burnt umber. Resin or chios turpentine may be added till the varnish has attained the desired thickness.
The longer the raw linseed-oil remains on the unslaked lime or umber, the sooner will the oil dry after it is used; if some months, so much the better. Such varnish will set, that is to say, not run, but keep its place on the silk in four hours; the silk may then be turned and varnished on the other side.
Take of pure alcohol, 32 oz.; purified mastic, 6 oz.; gum sandarac, 3 oz.; very clear Venice turpentine, 3 oz., glass, coarsely pounded, 4 oz.
Reduce the mastic and sandarac to fine powder; mix this powder with white glass, from which the finest parts have been separated by means of a hair-sieve; put all the ingredients with alcohol into a short-necked matrass, and adapt to it a stick of white-wood, rounded at the end, and of a length proportioned to the height of the matrass, that it may be put in motion. Expose the matrass in a vessel filled with water, made at first a little warm, and which must afterwards be maintained in a state of ebullition for 1 or 2 hours. The matrass may be made fast to a ring of straw.
When the solution seems to be sufficiently extended, add the turpentine, which must be kept separately in a phial or pot, and which must be melted by immersing it for a moment in a balneum maria. The matrass must be still left in the water for 1/2 hour, at the end of which it is taken off, and the varnish is continually stirred till it is some. what cool. Next day it is to be drawn off and filtered through cotton. By these means it will become exceedingly limpid.
The addition of glass may appear extraordinary; but this substance divides the parts of the mixture which have been made with the dry ingredients; and it retains the same quality when placed over the fire. It therefore obviates with success two inconveniences which are exceedingly troublesome to those who compose varnishes. In the first place, by dividing the matters, it facilitates the action of the alcohol; and in the second, its weight, which surpasses that of resins, prevents these resins from adhering to the bottom of the matrass, and also the coloration acquired by the varnish when a sand-bath is employed, as is commonly the case.
The application of this varnish is suited to articles belonging to the toilet, such as dressing-boxes, cut-paper works, etc. The following possess the same brilliancy and lustre, but they have more solidity, and are exceedingly drying.
Take of mastic, cleaned and washed, 12 oz.; pure turpentine, 1 1/2 oz.; camphor, 1/2 oz.; white glass pounded, 5 oz.; essence of turpentine, 36 oz. Make the varnish according to the method indicated for Compound Mastic Varnish. The camphor is employed in pieces, and the turpentine is added when the solution of the resin is completed. But if the varnish is to be applied to old paintings, or paintings which have been already varnished, the turpentine may be suppressed; as this ingredient is here recommended only in cases of a first application to new paintings, and just freed from white-of-egg varnish.
The question by able masters respecting the kind of varnish proper to be employed for paintings, has never yet been determined. Some artists who have paid particular attention to this subject make a mystery of the means they employ to obtain the desired effect. The real end may be accomplished by giving to the varnish destined for painting, pliability and softness, without being too solicitous in regard to what may add to its consistence or its solidity. The latter quality is particularly requisite in varnishes which are to be applied to articles much exposed to friction; such as boxes, furniture, etc.
Bruise the mastic with a muller on a painter's stone, which will detect the soft parts, or tears, which are to be taken out, and the remainder put into a clean bottle with good spirits of turpentine (twice distilled if you can get it), and dissolve the gum by shaking it in your hand for 1/2 hour, without heat. When dissolved, strain it through a piece of calico and place it in a bottle well corked, so that the light of the sun can strike it, for 2 or 3 weeks; which will cause a mucilaginous precipitate, leaving the remainder as transparent as water. It may then be carefully decanted into another bottle and put by for use. The proportions of gum and alcohol are: mastic, 6 oz., turpentine, 14 oz. If found on trial to be too thick, thin it with turpentine.
Painters who have long intervals between their periods of labor, are accustomed to cover the parts they have painted with a preparation which preserves the freshness of the colors, and which they can remove when they resume their work. This preparation is as follows:
Take of very clear nut-oil, 3 oz.; mastic in tears, pulverized, 1/2 oz.; sal saturni, in powder (acetate of lead), 1/3 oz. Dissolve the mastic in oil over a gentle fire, and pour the mixture into a marble mortar, over the pounded salt of lead, stir it with a wooden pestle, and add water in smell quantities, till the matter assume the appearance and consistence of cream, and refuse to admit more water.
Take of gum sandarac, 8 oz.; pounded mastic 2 oz.; clear turpentine, 2 1/2 oz.; pounded glass, 4 oz.; pure alcohol, 32 oz. Mix and dissolve as before.
Take of pounded copal, of an amber color, once liquified, 3 oz.; gum sandarac, 6 oz.; mastic, cleaned, 3 oz.; clear turpentine, 3 1/2 oz.; pounded glass, 4 oz.; pure alcohol, 32 oz. Mix these ingredients, and pursue the same method as above.
This varnish is destined for articles subject to friction; such as furniture, chairs, fan-sticks, mouldings, etc., and even metals, to which it may be applied with success. The sandarac gives it great durability.
Take of gum sandarac, 6 oz.; gum elemi, 4 oz.; gum animi, 1 oz.; camphor, 1/2 oz.; pounded glass, 4 oz.; pure alcohol, 32 oz.
Make the varnish according to the directions already given. The soft resins must be pounded with the dry bodies. The camphor is to be added in pieces
Another. - Take of gallipot or white incense, 6 oz.; gum animi, gum elemi, each 2 oz.; pounded glass, 4 oz., alcohol, 32 oz.
Make the varnish with the precautions indicated for the compound mastic varnish.
The two last varnishes are to be used for ceilings and wainscots, colored or not colored. They may even be employed as a covering to parts painted with strong colors.
Take gum sandarac, 6 oz.; shell-lac, 2 oz.; colophonium or resin, white glass pounded, clear turpentine, each 4 oz.; pure alcohol, 32 oz.
Dissolve the varnish according to the directions given for compound mastic varnish.
This varnish is sufficiently durable to be applied to articles destined to daily and continual use. Varnishes composed with copal, ought however, in these cases to be preferred.
Another. - There is another composition which without forming part of the compound varnishes is employed with success for giving a polish and lustre to furniture made of wood; wax forms the basis of it.
Many cabinet-makers are contented with waxing common furniture, such as tables, chests of drawers, etc, This covering, by means of repeated friction, soon acquires a polish and transparency which resembles those of varnish. Waxing seems to possess qualities peculiar to itself, but, like varnish, it is attended with inconveniences as well as advantages.
Varnish supplies better the part of glazing; it gives a lustre to the wood which it covers, and heightens the colors of that destined, in particular, for delicate articles. These real and valuable advantages are counterbalanced by its want of consistence; it yields too easily to the shrinking or swelling of the wood, and rises in scales or splits on being exposed to the slightest shock. These accidents can be repaired only by new strata of varnish, which render application to the varnisher necessary, and occasion trouble and expense.
Waxing stands shocks, but it does not possess in the same degree as varnish the property of giving lustre to the bodies on which it is applied and of heightening their tints. The lustre it communicates is dull, but this inconvenience is compensated by the facility with which any accident that may have altered its polish can be repaired by rubbing it with a piece of fine cork. There are some circumstances, therefore, under which the application of wax ought to be preferred to that of varnish. This seems to be the case in particular with tables of walnut-tree wood, exposed to daily use, chairs, mouldings and for all small articles subject to constant employment.
But as it is of importance to make the stratum of wax as thin as possible in order that the veins of the wood may be more apparent, the following process will be acceptable to the reader:
Melt over a moderate fire in a very clean vessel 2 oz. of white or yellow wax, and when liquefied add 4 oz. of good essence of turpentine; stir the whole until it is entirely cool, and the result will be a kind of pomade fit for waxing furniture, and which must be rubbed over them according to the usual method. The essence of turpentine is soon dissipated, but the wax, which by its mixture is reduced to a state of very great division, may be extended with more ease and in a more uniform manner. The essence soon penetrates the pores of the wood, calls forth the color of it, causes the wax to adhere better, and the lustre which thence results is equal to that of varnish without having any of its inconveniences.
Gum sandarac, 4 oz.; seed-lac, 2 oz.; mastic, Benjamin, in tears, each 1 oz.; pounded glass, 4 oz.; Venice turpentine, 2 oz.; pure alcohol, 32 oz.
The gum sandarac and lac render this varnish durable; it may be colored with a little saffron or dragon's blood.
The varnish being prepared (shellac), the article to be polished being finished off as smoothly as possible with glass-paper, and your rubber being prepared as directed below, proceed to the operation as follows: The varnish, in a narrow necked bottle, is to be applied to the middle of the flat face of the rubber, by laying the rubber on the mouth of the bottle and shaking up the varnish once, as by this means the rubber will imbibe the proper quantity to varnish a considerable extent of surface. The rubber is then to be enclosed in a soft linen cloth doubled, the rest of the cloth being gathered up at the back of the rubber to form a handle. Moisten the face of the linen with a little raw linseed-oil, applied with the finger to the middle of it. Placing your work opposite the light, pass your rubber quickly and lightly over its surface until the varnish becomes dry or nearly so; charge your rubber as before with varnish (omitting the oil), and repeat the rubbing until three coats are laid on, when a little oil may be applied to the rubber and two coats more given to it. Proceeding in this way until the varnish has acquired some thickness, wet the inside of the linen cloth, before applying the varnish, with alcohol, and rub quickly, lightly and uniformly the whole surface. Lastly, wet the linen cloth with a little oil and alcohol without varnish, and rub as before till dry.
Roll up a strip of thick woolen cloth which has been torn off so as to form a soft, elastic edge. It should form a coil from 1 to 3 inches in diameter, according to the size of the work.
Amber, 8 oz.; gum-lac, 2 oz.; drying linseed-oil, 8 oz.; essence of turpentine, 16 oz. Dissolve separately the gum-lac, and then add the amber, prepared and pulverized, with the linseed-oil and essence very warm. When the whole has lost a part of its heat, mix in relative proportions tincture of anatto, of terra merita, gum guttae and dragon's blood. This varnish, when applied to white metals, gives them a gold color.
Boiled linseed oil, 16 oz.; Venice turpentine, 8 oz.; Naples yellow, 5 oz. Heat the oil with the turpentine, and mix the Naples yellow pulverized.
Naples yellow is substituted here for resins, on account of its drying qualities. and in particular of its color, which resembles that of gold; great use is made of the varnish in applying gold leaf.
The yellow, however, may be omitted when this species of varnish is to be solid and colored coverings. In this case an ounce of litharge to each pound of composition may be substituted in its stead, without this mixture doing any injury to the color which is to constitute the ground.
Seed-lac, 5 oz.; gum sandarac, 2 oz.; gum elemi, 1 1/2 oz.; Venice turpentine, 2 oz.; pounded glass, 5 oz.; pure alcohol, 24 oz.
Another. - Other turners employ the gum-lac united to a little elemi and turpentine digested some months in pure alcohol exposed to the sun. If this method be followed, it will be proper to substitute for the sandarac the same quantity of gum-lac reduced to powder, and not to add the turpentine to the alcohol, which ought to be exceedingly pure, till towards the end of the infusion.
Solar infusion requires care and attention. Vessels of a sufficient size to allow the spirituous vapors to circulate freely ought to be employed, because it is necessary that the vessels should be closely shut. Without this precaution the spirits would become weakened and abandon the resin which they laid hold of during the first day's exposure. This perfect obituration will not admit of the vessels being too full.
In general the varnishes applied to articles which may be put into the lathe acquire a great deal of brilliancy by polishing: a piece of woollen cloth is sufficient for the operation. If turpentine predominates too much in these compositions, the polish does not retain its lustre, because the heat of the hands is capable of softening the surface of the varnish, and in this state it readily tarnishes.
For this varnish a prize of 20 guineas was awarded by the Society of Arts, London. Dissolve 2 1/2 oz. of shellac in a pint of alcohol; boil for a few minutes with 5 oz. of wellburned and recently-heated animal charcoal. A small portion of the solution must then be filtered, and if not colorless more charcoal must be added. When all color is removed, press the liquid through a piece of silk, and afterwards filter through fine blotting paper. This varnish should be used in a room of at least 60° Fahr., and free from dust. It dries in a few minutes, and is not liable afterwards to chill or bloom. It is particularly applicable to drawings and prints which have been sized, and may be advantageously used upon oil paintings, which are thoroughly hard and dry, as it brings out the colors with the purest effect. This quality renders it a valuable varnish for all kinds of leather, as it does not yield to the warmth of the hand and resists damp.
Dissolve in an iron kettle 1 part of pearlash in about 8 parts of water; add 1 part of seed or shellac, and heat to boiling. When the lac is dissolved impregnate the whole with chlorine (made by gently heating 1 part black oxide of manganese with 4 of muriatic acid) until the lac is all precipitated. Wash, dry, and dissolve in alcohol.
The most of spirit of wine varnishes are destined for covering preliminary preparations, which have a certain degree of lustre. They consist of cement, colored or not colored, charged with landscapes and figures cut out in paper, which produces an effect under the transparent varnish. Most of the dressing-boxes, and other small articles of the same kind, are covered with this particular composition, which, in general, consists of three or four coatings of Spanish white pounded in water, and mixed up with parchment glue. The first coating is smoothed with pumicestone, and then polished with a piece of new linen and water. The coating in this state is fit to receive the destined color, after it has been ground with water and mixed with parchment glue diluted with water. The cut figures with which it is to be embellished are then applied, and a coating of gum or fish-glue is spread over them, to prevent the varnish from penetrating to the preparation, and from spoiling the figures. The operation is finished by applying 3 or 4 coatings of varnish, which when dry are polished with tripoli and water, by means of a piece of cloth. A lustre is then given to the surface with starch and a bit of doe-skin, or very soft cloth.
Take of gallipot, or white incense, 12 oz.; white glass, pounded, 5 oz.; Venice turpentine, 2 oz.; essence of turpentine, 32 oz. Make the varnish after the white incense has been pounded with the glass.
Some authors recommend mastic or sandarac in the room of gallipot, but the varnish is neither more beautiful nor more durable. When the color is ground with the preceding varnish and mixed up with the latter, which, if too thick, is thinned with a little essence, and which is applied immediately, and without any sizing, to boxes and other articles, the coatings acquire sufficient strength to resist the blows of a mallet. But if the varnish be applied to a sized color it must be covered with a varnish of the first or second genus.
Dissolve the best red sealing-wax in alcohol. Two or three coats will make a complete covering. It may be applied to wood or glass.
Take of new gallipot, or white incense, 4 oz.; mastic, 2 oz.; Venice turpentine, 6 oz.; pounded glass, 4 oz.; essence of turpentine, 32 oz. Where the varnish is made with the precautions already indicated, add prepared nut-oil or linseed-oil, 2 oz.
The matters ground with this varnish dry more slowly, they are then mixed up with the following varnish, if it be for common painting, or with particular varnishes destined for colors and for grounds.
Take of seed-lac, 6 oz.; amber or copal, ground on porphyry, 2 oz.; dragon's blood, 40 grs.; extract of red sandal-wood, obtained by water, 30 grs.; oriental saffron, 36 grs.; pounded glass, 4 oz.; very pure alcohol, 40 oz.
To apply this varnish to articles or ornaments of brass, expose them to a gentle heat, and dip them into varnish. Two or three coatings may be applied in this manner, if necessary. The varnish is durable and has a beautiful color. Articles varnished in this manner may be cleaned with water and a bit of dry rag.
This lacquer or varnish is destined to change or to modify the color of those bodies to which it is applied.
Take of gum guttae (gamboge), 3/4 oz.; gum sandarac, gum elemi, each 2 oz.; dragon's blood, of the best quality, 1 oz.; seed-lac, 1 oz.; terra merita, 3/4 oz.; oriental saffron, 2 grs.; pounded glass, 3 oz.; pure alcohol, 20 oz.
The tincture of saffron and of terra merita is first obtained by infusing them in alcohol for 24 hours, or exposing them to the heat of the sun in summer. The tincture must be strained through a piece of clean linen cloth, and ought to be strongly squeezed. This tincture is poured over the dragon's blood, the gum elemi, the seed-lac, and the gum guttae, all pounded and mixed with the glass. The varnish is then made according to the directions before given.
It may be applied with great advantage to philosophical instruments. The use of it might be extended also to various cast or moulded articles with which furniture is ornamented.
If the dragon's blood be of the first quality it may give too high a color; in this case the dose may be lessened at pleasure, as well as that of the other coloring matters.
Take of seed-lac, 6 oz.; amber, gum guttae, each 2 oz.; extract of red sandal-wood in water, 24 grs.; dragon's blood, 60 grs.; oriental saffron, 36 grs.; pounded glass, 4 oz.; pure alcohol, 36 oz. Grind the amber, the seed-lac, gum guttae, and dragon's blood on a piece of porphyry; then mix them with the pounded glass, and add the alcohol, after forming with it an infusion of the saffron and an extract of the sandal-wood. The varnish must then be completed as before. The metal articles destined to be covered by this varnish are heated and those which will admit of it are immersed in packets. The tint of the varnish may be varied by modifying the doses of the coloring substances.
Take of seed-lac, 4 oz.; sandarac, or mastic, 4 oz.; dragon's blood, 1/2 oz.; terra merita, gum guttae, each 30 grs.; pounded glass, 5 oz.; clear turpentine, 8 oz.; essence of turpentine, 32 oz. Extract by infusion the tincture of the coloring substances, and then add the resinous bodies according to the directions for compound mastic varnish.
Lacquer or varnishes of this kind are called changing, because, when applied to metals, such as copper, brass, or hammered tin, or to wooden boxes and other furniture, they communicate to them a more agreeable color. Besides, by their contact with the common metals, they acquire a lustre which approaches that of the precious metals, and to which, in consequence of peculiar intrinsic qualities or certain laws of convention, a much greater value is attached. It is by means of these changing varnishes that artists are able to communicate to their leaves of silver and copper those shining colors observed in foils. This process of industry becomes a source of prosperity to the manufacturers of buttons and works formed with foil, which in the hands of the jeweller contributes with so much success to produce that reflection of the rays of light which doubles the lustre and sparkling quality of precious stones.
It is to varnish of this kind that we are indebted for the manufactory of gilt leather, which, taking refuge in England, has given place to that of papier-mache, which is employed for the decoration of palaces, theatres, etc.
In the last place, it is by the effect of a foreign tint, obtained from the coloring part of saffron, that the scales of silver disseminated in confection d'hyacinthe reflect a beautiful gold color.
The colors transmitted by different coloring substances, require tones suited to the objects for which they are destined. The artist has it in his own power to vary them at pleasure, by the addition of anatto to the mixture of dragon's blood, saffron, etc., or some changes in the doses of the mode intended to be made in colors. It is here impossible to give limited formula.
There is one simple method by which artists may be enabled to obtain all the different tints they require. Infuse separately 4 oz. of gum guttae in 32 oz. of essence of turpentine, and 4 oz. of dragon's blood, and 1 oz. of annatto also in separate doses of essence. These infusions may be easily made in the sun. After 15 days exposure pour a certain quantity of these liquors into a flask, and by varying the doses different shades of color will be obtained.
These infusions may be employed also for changing alcoholic varnishes, but in this case the use of saffron, as well as that of red sandal-wood which does not succeed with essence, will soon give the tone necessary for imitating with other tinctures the color of gold.
Take of mastic, 1 oz.; gum sandarach, 1 oz.; gum guttae, 1/2 oz.; turpentine, 1/4 oz.; essence of turpentine, 6 oz.
Some artists, who make use of mordants, substitute for the turpentine 1 oz. of the essence of lavender, which renders this composition still less drying.
In general, the composition of mordants admits of modifications, according to the kind of work for which they are destined. The application of them, however, is confined chiefly to gold. When it is required to fill up a design with gold-leaf on any ground whatever, the composition, which is to serve as the means of union between the metal and the ground, ought to be neither too thick nor too fluid, because both these circumstances are equally injurious to delicacy in the strokes; it will be requisite also that the composition should not dry till the artist has completed his design
Some prepare their mordants with Jew's pitch and drying oil diluted with essence of turpentine. They employ it for gilding pale gold, or for bronzing.
Other artists imitate the Chinese, and mix with their mordants colors proper for assisting the tone which they are desirous of giving to the gold, such as yellow, red, etc.
Others employ merely fat varnish, to which they add a little red oxide of lead (minium).
Others make use of thick glue, in which they dissolve a little honey. This is what they call batture. When they are desirous of heightening the color of the gold, they employ this glue, to which the gold-leaf adheres exceedingly well.
Another. - The qualities of the following are fit for every kind of application, and particularly to metals: Expose boiled oil to a strong heat in a pan; when a black smoke is disengaged from it, set it on fire, and extinguish it a few moments after by putting on the cover of the pan. Then pour the matter still warm into a heated bottle, and add to it a little essence of turpentine. This mordant dries very speedily; it has body and adheres to, and strongly retains, gold-leaf, when applied to wood, metals, and other substances.
Take of Canada balsam, 1 oz.; spirit of turpentine, 2 oz.; mix them together. Before this composition is applied, the drawing or print should be sized with a solution of isinglass in water, and when dry, apply the varnish with a camel's-hair brush.
Take either red, black, or white sealing-wax, whichever color you wish to make; to every 2 oz. of sealingwax, add 1 oz. of spirit of wine; pound the wax fine, then sift it through a fine lawn sieve, till you have made it extremely fine; put it into a large phial with the spirit of wine, shake it, let it stand near the fire 48 hours, shaking it often; then, with a little, brush the baskets all over with it; let them dry, and do them over a second time.
According to the specification of the patent, this mixture consists of 1 cwt. of plumbago, to 4 cwt. of hog's lard, or other grease, the two to be well incorporated. The application is to prevent the affects of friction in all descriptions of engines or machines, and a sufficient quantity must be rubbed over the surface of the axle, spindle, or other part where the bearing is.
A French lubricating compound, is thus made: Into 50 parts of the finest rape-oil put 1 part of India-rubber, cut into strips, and apply a gentle heat until nearly dissolved.
Take any quantity of tar, and grind it with as much Spanish-brown as it will bear, without rendering it too thick to be used as a paint or varnish, and then spread it on the poles, or other wood, as soon as convenient, for it quickly hardens by keeping.
This mixture must be laid on the wood to be varnished by a hard brush, or house-painter's tool; and the work should then be kept as free from dust and insects as possible, till the varnish is thoroughly dry. It will, if laid on smooth wood, have a very good gloss, and is an excellent preservative of it against moisture; on which account, as well as its being cheaper, it is far preferable to painting, not only for pales, but for weather-boarding, and all other kinds of woodwork for grosser purposes. Where the glossy brown color is not liked, the work may be made of a grayishbrown, by mixing a small proportion of white lead, or whiting and ivory black, with the Spanish-brown. Boiled coal-tar is extensively used for the same purpose.
Take of best black sealing-wax, 1/2 oz.; rectified spirit of wine, 2 oz.; powder the sealing-wax, and put it with the spirit of wine into a 4 oz. phial; digest them in a sand-heat, or near a fire, till the wax is dissolved; lay it on warm with a fine soft hair-brush, before a fire or in the sun. It gives a good stiffness to old straw hats, and a beautiful gloss, equal to new, and resists wet.
Take of good yellow soap, cut into slices, 2 1/2 lbs.; boiling water, 1 1/2 galls. Dissolve, and grind the solution while hot with 1 1/4 cwt. of good oil-paint. Used to paint on canvas.
This quality is given to cloth by simply passing it through a hot solution of weak glue and alum. To apply it to the cloth, make up a weak solution of glue, and while it is hot add a piece of alum (about 1 oz. to 2 qts.), and then brush it over the surface of the cloth while it is hot, and it is afterwards dried. Cloth in pieces may be run through this solution, and then run out of it and dried. By adding a few pieces of soap to the glue, the cloth will feel much softer. Goods in pieces may be run through a tubfull of weak glue, soap, and alum, and squeezed between rollers. This would be a cheap and expeditious mode of preparing them. Woollen goods are prepared by brushing them with the above mixture first in the inside, then with the grain or nap of the cloth; after which it is dried. It is the best to dry this first in the air, and then in a stove-room at a low heat; but allow the cloth to remain for a considerable time, to expel the moisture completely. This kind of cloth, while it is sufficiently water-proof to keep out the moisture and rain, being quite impervious to water, is pervious to the air.
Grind whiting with zinc (white), and to prevent its cracking add a little honey to it; then take a soft brush and lay it upon the cloth, and so do 2 or 3 times, suffering it the meanwhile to dry between layings on; and for the last laying smooth it over with Spanish white ground with linseedoil, the oil being first heated and mixed with a small quantity of the litharge of gold, the better to endure the weather; and so it will be lasting.
The manufacture of this kind of cloth is very simple. The cloth and linseed-oil are the principal articles required for the establishment. Common canvas, of an open and coarse texture, is extended on large frames placed under sheds, the sides of which are open, so as to afford a free passage to the external air. The manner in which the cloth is fastened to these frames is as follows: it is fixed to each side of the frame by hooks which catch the edge of the cloth, and by pieces of strong packthread passing through holes at the other extremity of the hooks, which are tied around movable pegs in the lower edge of the frame. The mechanism by which the strings of a violin are stretched or unstretched, will give some idea of the arrangement of the pegs employed for extending the cloth in this apparatus. By these means the cloth can be easily stretched or relaxed, when the oily varnish has exercised an action on its texture in the course of the operation. The whole being thus arranged, a liquid paste made with drying-oil, which may be varied at pleasure, is applied to the cloth.
Mix Spanish white, or tobacco-pipe clay, or any other argillaceous matter with water, and leave it at rest some hours, which will be sufficient to separate the argillaceous parts, and to produce a sediment. Stir the sediment with a broom, to complete the division of the earth; and after it has rested some seconds, decant the turbid water into an earthen or wooden vessel. By this process the earth will be separated from the sand and other foreign bodies, which are precipitated and which must be thrown away. If the earth has been washed by the same process on a large scale, it is divided by kneading it. The supernatant water is thrown aside and the sediment placed in sieves, on pieces of cloth, where it is suffered to drain; it is then mixed up with oil rendered drying by a large dose of litharge, that is about a fourth of the weight of the oil. The consistence of thin paste being given to the mixture, it is spread over the cloth by means of an iron spatula, the length of which is equal to that of the breadth of the cloth. This spatula performs the part of a knife, and pushes forward the excess of matter above the quantity sufficient to cover the cloth. When the first stratum is dry, a second is applied. The inequalities produced by the coarseness of the cloth, or by an unequal extension of the paste are smoothed down with pumice-stone. The pumice-stone is reduced to powder and rubbed over the cloth with a piece of soft serge or cork dipped in water. The cloth must then be well washed in water to clean it; and after it is dried, a varnish of gum-lac dissolved in linseedoil boiled with turpentine, is to be applied to it.
This preparation produces yellowish varnished cloth. When wanted black, mix lampblack with the Spanish white or tobacco-pipe clay, which forms the basis of the liquid paste. Various shades of gray may be obtained, according to the quantity of lampblack which is added. Umber, Cologne-earth, and different ochry argillaceous earths, may be used to vary the tints, without causing any addition to the expense.
Varnished silk, for making umbrellas, capots, coverings for hats, etc., is prepared in the same manner as the varnished and polished cloths already described, but with some variation in the liquid paste or varnish.
If the surface of the silk be pretty large, it is made fast to a wooden frame furnished with hooks and movable pegs, such as that used in the manufacture of common varnished cloths. A soft paste, composed of linseed-oil boiled with a fourth part of litharge; tobacco-pipe clay dried and sifted through a silk sieve, 16 parts; litharge, ground on porphyry with water, dried and sifted in the same manner, 3 parts, and lampblack, 1 part. This paste is then spread in a uniform manner over the surface of the silk by means of a long knife, having a handle at each extremity. In summer, 24 hours are sufficient for its desiccation. When dry, the knots produced by the inequalities of the silk are smoothed with pumicestone. This operation is performed with water, and, when finished, the surface of the silk is washed. It is then suffered to dry, and fat copal varnish is applied.
If it be intended to polish this varnish, apply a second stratum, after which polish it with a ball of cloth and very fine tripoli. The varnished silk thus made is very black, exceedingly pliable, and has a fine polish. It may be rumpled a thousand ways without retaining any fold, or even the mark of one. It is light, and therefore proper for coverings to hats, and for making cloaks and caps so useful to travellers in wet weather.
A kind of varnished silk, which has only a yellowish color, and which suffers the texture of the stuff to appear, is prepared with a mixture of 3 parts boiled oil of pinks, or linseed-oil, and 1 part of fat copal varnish, which is extended with a coarse brush or knife. Two strata are sufficient when oil has been freed from its greasy particles over a slow fire, or when boiled with a fourth part of its weight of litharge.
The inequalities are removed by pumice-stone and water, after which the copal varnish is applied. This simple operation gives to white silk a yellow color. which arises from the boiled oil and the varnish
This varnished silk possesses all those qualities ascribed to certain preparations of silk which are recommended to be worn as jackets by persons subject to rheumatism.
1. Boots and shoes may be rendered impervious to water by the following composition: Take 3 oz. of spermaceti and melt it in a pipkin, or other earthen vessel, over a slow fire; add thereto 6 drs. of India-rubber, cut into slices, and these will presently dissolve. Then add, seriatim, of tallow, 8 oz.; hog's lard, 2 oz.; amber varnish 4 oz. Mix, and it will be fit for use immediately. The boots or other material to be treated are to receive 2 or 3 coats with a common blacking-brush, and a fine polish is the result.
2. Half-pound of shoemaker's dubbing; 1/2 pt. of linseed-oil; 3 pt. of solution of India-rubber. Dissolve with a gentle heat (it is very inflammable), and rub on the boots. This will last for several months.
Digest India-rubber, cut into small pieces, in benzine for several days, frequently shaking the bottle containing the materials. A jelly will be formed, which will separate from the benzine; this dissolved in the fixed and volatile oils, dries fast, does not crack or shine, unless mixed with some resinous substance.
Gutta-percha, in small slices, 1 1/2 oz.; chloroform, 12 fluidounces. To 8 fluidounces of the chloroform contained in a bottle, add the gutta-percha, and shake occasionally till dissolved, then add the carbonate of lead, previously mixed smoothly with the remainder of the chloroform, and, having shaken the whole thoroughly together several times at intervals of 1/2 hour, set the mixture aside, and let it stand for 10 days, or until the insoluble matter has subsided, and the solution has become limpid, and either colorless or of a slight straw-color. Lastly, decant, and keep the solution in a glass-stopped bottle.
Boiled oil, 1 gall.; umber, 8 oz.; asphaltum, 3 oz. oil of turpentine, as much as will reduce it to the thinness required.
After the adoption of glazing, varnishing, etc., to increase the hardness of tiles, tarring has been found completely to stop their pores, and to render them impervious to water. This process is practicable, and not expensive. Lime and tar, whale-oil or dregs of oil, are equally adapted to the purpose, and still cheaper. Tarring is particularly efficacious when tiles are cracked by the frost. It is calculated that the expense of coal-tar for a roof of a middling extent, and supposing such a roof to require one hundredweight, would not exceed 15 dollars.
For the ground, after it has been sized and rubbed down, take Prussian blue, verditer and spruce ochre; grind them separately in water, turpentine, or oil, according to the work, and mix them in such proportions as will produce the color desired; then grind Dutch metal in a part of this composition, laying it with judgment on the prominent parts of the figure, which produces a grand effect.
Take 2 oz. of tripoli powdered, put it in an earthen pot with water to cover it, then take a piece of white flannel, lay it over a piece of cork or rubber, and proceed to polish the varnish, always wetting it with the tripoli and water. It will be known when the process is finished by wiping a part of the work with a sponge, and observing whether there is a fair even gloss. When this is the case, take a bit of mutton suet and fine flour and clean the work.
Take a piece of pumice-stone and water, and pass regularly over the work until the rising of the grain is cut down; then take powdered tripoli and boiled linseed-oil, and polish the work to a bright surface.
File the brass very clean with a smooth file then take some tripoli powdered very fine, and mix it with the linseed oil. Dip in this a rubber of felt, with which polish the work until the desired effect is obtained.
If the work is ebony, or black rosewood, take some elder coal powdered very fine, and apply it dry after you have done with the tripoli, and it will produce a superior polish.
The French mode of ornamenting with brass differs widely from ours, theirs being chiefly water-gilt (or-moulu), excepting the flutes of columns, etc. which are polished very high with rotten-stone, and finished with elder coal.
Dissolve 2 parts of crystallized chloride of iron, 2 parts of solid chloride of antimony, and 1 part of gallic acid in 4 or 5 parts of water. With this moisten a piece of sponge or cloth and apply to the object, a gun-barrel for instance. Let it dry in the air, and repeat the operation several times, then wash with water; dry, and rub with boiled linseed-oil. Objects browned in this way have a very agreeable dead gray appearance, and the shade deepens according to the number of times the operation is repeated.
Take of ivory black and treacle, each 12 oz.; spermaceti oil, 4 oz.; white wine vinegar, 4 pts. Mix.
Take of vinegar, No. 18 (the common), 1 qt.; ivoryblack and treacle, each 6 oz.; vitriolic acid and spermaceti (or common oil), each 1 1/2 oz.
Mix the acid and oil first, afterwards add the other ingredients; if, when it is used, it does not dry quickly enough on the leather, add a little more of the vitriol, a little at a time, till it dries quickly enough. When there is too much of the vitriolic acid, which is various in its strength, the mixture will give it a brown color.
Vinegar is sold by numbers, viz., No. 18 (the weakest), 19, 20, 21, 22. The celebrated blacking is made with No. 18. When this mixture is properly finished, the ivory-black will be about one-third the contents of the bottle.
Take gum tragacanth, 1 oz.; neat's-foot oil, superfine ivory-black, deep blue, prepared from iron and copper, each 2 oz.; brown sugar candy, river-water, each 4 oz. Having mixed well these ingredients, evaporate the water, and form your cakes.
Take mutton suet, 4 oz.; bees-wax, 1 oz.; sweet oil, 1 oz.; sugar candy and gum Arabic, 1 dr. each, in fine powder; melt these well together over a gentle fire, and add thereto about a spoonful of turpentine, and lampblack sufficient to give it a good black color. While hot enough to run, make it into a ball by pouring the liquor into a tin mould; or let it stand till almost cold; or it may be moulded by the hand.
Take 3 oz. of ivory-black, 2 oz. of coarse sugar, 1 oz. of sulphuric acid, 1 oz. of muriatic acid, 1 tablespoonful of sweet oil and lemon acid, and 1 pt. of vinegar. First mix the ivory-black and sweet oil together, then the lemon and sugar, with a little vinegar to qualify the blacking, then add the sulphuric and muriatic acids, and mix them all well together.
Observation. - The sugar, oil, and vinegar prevent the acids from injuring the leather, and add to the lustre of the blacking.
Ivory-black, 2 oz.; brown sugar, 1 1/2 oz.; and sweet oil, 1/2 tablespoonful. Mix them well, and then gradually add 1/2 pt. of small beer.
A quarter lb. of ivory-black, 1/4 lb. of moist sugar, a tablespoonful of flour, a piece of tallow about the size of a walnut, and a small piece of gum Arabic. Make a paste of the flour, and while hot put in the tallow then the sugar, and afterwards mix the whole well together in a quart of water.
Ivory-black, 60 lbs,; treacle, 45 lbs.; vinegar (No. 24) 20 galls.; powdered gum, 1 lb.; India-rubber oil, 9 lbs. (The latter is made by dissolving by heat 18 oz. of India rubber in 9 lbs. of rape-oil.) Grind the whole smooth in a paint-mill, then add by small quantities at a time 12 lbs. of oil of vitriol, stirring it strongly for 1/2 an hour a day for a fortnight.
This is done by rubbing or brushing into the leather a mixture of drying oils, and any of the oxides of lead, copper, or iron; or by substituting any of the gummy resins in the room of the metallic oxides.
Take of Canada balsam, 1 oz.; spirit of turpentine, 2 oz. Mix them together. Before this composition is applied, the drawing or print should be sized with a solution of isinglass in water; and when dry apply the varnish with a camel's-hair brush
Scrape 4 oz. of bees'-wax into a basin, and add as much oil of turpentine as will moisten it through. Now powder a 1/4 oz. of resin, and add as much Indian red as will bring it to a deep mahogany color. When the composition is properly stirred up, it will prove an excellent cement or paste for blemishes in mahogany and other furniture.
Scrape 4 oz. of beeswax as before. To a pint of oil of turpentine, in a glazed pipkin, add an ounce of alkanet-root. Cover it close and put it over a slow fire, attending it carefully that it may not boil over, or catch fire. When the liquid is of a deep red, add as much of it to the wax as will moisten it through, also a quarter of an ounce of powdered resin. Cover the whole close, and let it stand 6 hours, when it will be fit for use.
Take linseed-oil, put it into a glazed pipkin with as much alkanet-root as it will cover. Let it boil gently, and it will become of a strong red color; when cool it will be fit for use.
A thin wash of isinglass will fix either black lead, or hard black chalk, so as to prevent their rubbing out; or the same effect may be produced by the simple application of skimmed milk, as has been proved by frequent trials. The best way of using the latter is to lay the drawing flat upon the surface of the milk; and then taking it up by one corner till it drains and dries. The milk must be perfectly free from cream, or it will grease the paper.
Take 1 1/2 lbs. of linseed-oil, and boil it in a red copper vessel, not tinned, holding suspended over it, in a small linen bag, 5 oz. of litharge and 3 oz. of pulverized minium; taking care that the bag does not touch the bottom of the vessel. Continue the ebullition until the oil acquires a deep brown color, then take away the bag and substitute another in its place, containing a clove of garlic: continue the ebullition and renew the clove of garlic 7 or 8 times, or rather put them all in at once.
Then throw into the vessel 1 lb. of yellow amber, after having melted it in the following manner: Add to the pound of amber, well pulverized, 2 oz. of linseed oil, and place the whole on a strong fire. When the fusion is complete, pour it boiling into the prepared linseed-oil, and continue to leave it boiling for 2 or 3 minutes, stirring the whole up well. It is then left to settle; the composition is decanted and preserved, when it becomes cold, in well-corked bottles.
After polishing the wood on which this varnish is to be applied, you give to the wood the color required; for instance, for walnut-wood, a slight coat of a mixture of soot with the essence of turpentine. When this color is perfectly dry, give it a coat of varnish with a fine sponge. In order to spread it very equally, repeat these coats four times, taking care always to let the preceding coat be dried.
Many families, especially in the country, possess chairs, settees, etc. covered with black leather. These, impaired by long use, may be restored nearly to their original good color and gloss by the following easy and approved process: Take yolks of 2 newly-laid eggs and the white of one. Let these be well beaten up, and then shaken in a glass vessel or jug, to become like thick oil; dissolve in about a tablespoonful or less of geneva, an ordinary tea-lump of loaf-sugar; make this thick with ivory black, well worked up with a bit of stick; mix with the egg for use. Let this be laid on as blacking ordinarily is for shoes; after a very few minutes, polish with a soft, very clean brush, till completely dry and shining, then let it remain a day to harden.
The same process answers admirably for ladies' or gentlemen's dress-shoes, but with the following addition for protecting the stockings from oil. Let the white or glair of eggs be shaken in a large glass phial until it becomes a perfect oil, brush over the inner edges of the shoes with it, and when completely dry, it will prevent any soiling from the leather. This requires to be repeated.
The process for making ivory transparent and flexible is simply immersion in liquid phosphoric acid, and the change which it undergoes is owing to a partial neutralization of the basic phosphate of lime, of which it principally consists. The ivory is cut in pieces not thicker than the twentieth part of an inch, and placed in phosphoric acid of a specific gravity of 1.131, until it has become transparent, when it is taken from the bath, washed in water, and dried with a clean linen cloth. It becomes dry in the air without the application of heat, and softens again under warm water.
Ivory knife-handles which have become quite yellow from use, being left for from 2 to 4 hours in a watery solution of sulphurous acid, become quite white again. The acid in the gaseous form makes the ivory crack.
Boil some clear parchment cuttings in water in a glazed pipkin, till they produce a very clear size. Strain it and keep it for use.
Give the work 2 coats of the size, passing the brush quickly over the work, not to disturb the colors.
Mix 1 gall. of oil of turpentine and 5 lbs. of powdered resin: put it in a tin can, on a stove, and let it boil for 1/2 an hour. When cool it is fit for use.
There are at present five principal varieties of papier-mache known in the trade, viz.: 1. Sheets of paper pasted together upon models. 2. Thick sheets or boards produced by pressing ordinary paper pulp between dies. 3. Fibrous slab, which is made of the coarse varieties of fibre only, mixed with some earthy matter, and certain chemical agents introduced for the purpose of rendering the mass incombustible. A cementing size is added, and the whole well kneaded together with the aid of steam. The kneaded mass is passed repeatedly through iron rollers, which squeeze it out to a perfectly uniform thickness. It is then dried at a proper temperature. 4. Carton pierre, which is made of pulp or paper mixed with whiting and glue, pressed into plaster piece-moulds, backed with paper, and, when sufficiently set, hardened by drying in a hot room. 5. Martin's Ceramic Papiermache, a new composition, patented in 1858, which consists of paper pulp, resin, glue, drying oil, and sugar of lead, mixed in certain fixed proportions and kneaded together. This composition is extremely plastic, and may be worked, pressed, or moulded into any required form. It may be preserved in this plastic condition for several months by keeping the air away, and occasionally kneading the mass.
The first-mentioned variety of papier-mache alone engages our attention here. A special kind of paper, of a porous texture, is manufactured for this purpose. An iron mould, of somewhat smaller size than the object required, is greased with Russian tallow. A sheet of the paper is laid on to the greased surface of the mould, and covered over with a coat of paste made of the best biscuit flour and glue, which is spread evenly all over the sheet with the hands; another sheet is then laid on, and rubbed down evenly, so that the two 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 yellowish-brown 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 pumice-stone. 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-of-pearl. 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 darkcolored 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 brilliance, by 2 or 3 coats of copal or anime varnish. Superior articles receive as many as 6 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 with color. The inlaying 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.
M. Boettger 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 110 density. Into this liquid plunge the zinc, previously scoured with fine sand, then wash the metal with water, and dry it rapidly.
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.
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 markingnut, Semecarpus anacardium, and that of another kindred fruit, Holigarna longifolia.
The shell of the Semecarpus anacardium contains between its integuments numerous cells, filled 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 laminae numerous cells, filled with a black, thick, acrid fluid. The natives of Malabar extract by incision, with which they varnish targets.
To prepare the varnish according to the method practiced 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.
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.
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.
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 olive-oil, 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.
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 iridescent 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 6 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.
The following paint has been found successful. Flour of sulphur, 3088 grs.; common linseed-oil, 2084 grs.; refined oil of manganese, 463 grs.
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.
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