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will be a bright orange, like the acetate of iron. By exposure to heat and air this color generally deepens, becoming gray, and at last a full black. In this state it is permanent, and adheres powerfully to the cloth.

These changes of color depend on the solution of the tannate and gallate of iron in the disengaged nitrous acid, and the dissipation of the acid from the cloth, when it is exposed to heat and air. This solution of the tannate and gallate of iron is indeed an essential requisite to the goodness of the chemical black. If the disengaged acid is not sufficient to effect this, or if it is in a state of too great dilution, the color has but a feeble adherence to the cloth. It is not presented in a state favorable to its union with it, since the combination into which the iron has entered is insoluble in water. It lies merely on the surface, but does not penetrate its fibres, and gives way readily in the various operations to which it is subjected. This chemical black, therefore, is a solution of the tannate and gallate of iron in nitric acid.

Mordants for violets (from Vitalis). First violet.-Sixteen pints of iron liquor; eight pints of water; four ounces of Roman vitriol (sulphate of copper). This mixture is to be thickened with powdered gum, in the proportion of a pound to the pint.

Second violet.-Mix three parts of the preceding with one of water, and thicken as above. Third violet.-Dilute two parts of the first mordant with three of water.

Coffee color.-Ten pints of iron liquor; two pints of the mordant of the first red; four pints of water. Thicken with starch.

Pace, or carmelite color.-Three pints of mordant of the first red; half pint of iron liquor. Deep brown.-Two pints of red mordant; half pint of iron liquor.

Marroon color (chestnut-brown).—Two pints of violet mordant; one pint of red mordant; eight ounces of green copperas, to be dissolved in the mixed mordants.

Mordoré. Eight pints of violet mordant; twelve pints of red mordant.

Deep lilac-One pint of violet mordant; one pint of mordant for the second red.

Light lilac.-One pint of violet mordant; three pints of mordant of the second red.

Musk color.-One pint of red mordant; three pints of black mordant.

Incarnate (flesh) color; color between cherry and rose. Ten pints of red mordant; one pint of black mordant.

Olive color.-Welding on the mordant of the first, second, or third violet.

Résida color-Welding on puce mordant. We may now select from Vitalis some examples of the mode of managing the different styles of calico printing. We shall place them in the order in which they occur under each head. We may commence with

Calicoes of one block.-First example. Violet on a white ground. t. Impression of violet mordant; 2. Dunging and washing; 3. Maddering; 4. Branning and exposure on the grass for a few days, to clear the grounds.

Second example. Black on a yellow ground.
VOL. XVIII.

1. Bath of yellow mordant; 2. Welding; 3. Topical black.

Calicoes of two blocks.-First example. First olive and second olive on a white ground. 1. Impression of the first olive mordant; 2. Impression of the second olive mordant; 3. Welding.

Second example. Red and blue on a white ground. .1. Impression of the red mordant; 2. Maddering; 3. Impression by the block of topical blue. When the calico is to have several colors, says M. Vitalis, for example, black, several reds, several violets, &c., as many mordants must be given as there are different colors, which must be inserted (rentrés) into the first plate (figure), called the plate of impression (printing block, planche d'impression). The insertion (rentrage) of the mordants is executed by means of blocks (planches), which take the name of rentreures. These blocks are engraved with the same patterns as the printing blocks, but so as that they apply the new mordants only to the places of the pattern reserved in the first blocks. It may be readily conceived how necessary it is for these blocks to have an exact correspondence with one another, otherwise the colors would not be comprised within the limits of their outlines. This fault is too often met with in common prints, on account of the rapidity with which they are worked off, and the little care taken in their fabrication. In order that every color may occupy the place assigned to it in the drawn pattern (le dessein enluminé), adjusting brass points (picots de rapports) are made use of, which guide the printing on of the successive mordants, at precisely that place of the figure where the color to be produced from each mordant ought to fall.

Third example. Yellow and black on a white ground. 1. Impression of the yellow mordant, welding; 2. Impression of topical black.

Calicoes of three blocks.-Example. First olive, second olive, and yellow on a white ground. 1. Impression of the first olive mordant; 2. Impression of the second olive mordant; 3. Impression of the yellow mordant; 4. Welding.

The third block (main) might also be performed by the impression of the topical yellow.

Calicoes of four blocks.—Example. Black, red, violet, and yellow on white. 1. Impression of the black mordant; 2. Impression of the red mordant; 3. Maddering; 4. Impression of topical yellow, or of the yellow mordant, and welding.

Calicoes of five blocks.-Example. Black, red, violet, yellow, and blue. 1. Impression of the black mordant; 2. Impression of the red mordant; 3. Impression of the violet mordant; 4. Maddering, insertion of the blue, and afterwards of the yellow.

Calicoes of six blocks.-Example. First olive, second olive, black, first red, second red, and yellow on white ground. 1. Impression of the black mordant; 2. Impression of the first redmordant; 3. Impression of the second red mordant; 4. Maddering; 5. Impression of the second olive mordant; 6. Impression of the yellow mordant; 7. Welding.

It is now very seldom, however, that the numH

ber of three blocks (courses) is exceeded, on account of the high price to which the labor would necessarily raise the calico. The following is an example of printing in fugitive colors: violet, black, red, and yellow, on white ground. These four topical colors are successively applied, in the order above mentioned.

Calicoes with fast colors, after receiving the impressions, are dried, and washed. from the mordants, when they are ready for the maddering. Goods printed by reserve are so called, because the color does not strike the whole surface, but only certain unprotected portions of it. The reserve is composed of the reserve bath, and the thickening.

A reserve bath is thus formed: dissolve in a pint of water six ounces of sulphate of copper, three ounces of verdigris, two ounces of alum, and four ounces of gum arabic.

Another reserve bath may be noticed: dissolve in two litres of water four ounces of Roman vitriol (sulphate of copper), and six ounces of verdigris, to which add one pound of gum arabic; and, when it is dissolved, pass through a fine sieve, or let it settle, and decant.

To thicken the bath, knead a pound of pipeclay, well ground and sifted, with three or four ounces of water: with this thick dough carefully mix the reserve bath, and triturate well before making use of it. The reserve is printed on the goods like the mordants. Twenty-four hours after the impression the goods are to be passed through the dyeing vat. This style is much used in blue dipping.

The theory of the reserve is very simple. The oxide of copper, which forms the basis of the reserve, restores to the indigo the oxygen which it had been deprived of by the sulphate of iron. The reoxygenated indigo loses its solubility, and consequently cannot fix on the stuff. Since the reserve, intended to nullify the action of the indigo essentially, acts merely by the oxide of copper which it contains, it follows that the proportions of this oxide are not indifferent, and that the measure will not perfectly accomplish its end, unless the dose of oxide of copper, which the sulphate, &c., can furnish, be adequate to neutralize the action of the indigo. A similar result would ensue, if the reserve be not suitably thickened. Some object to the introduction of alum.

The proportions of the cupreous salts ought, however, to be as little as can effect the purpose; if their quantity be too great, their operation would be extended to the indigo diffused through the bath. Sometimes the sulphate of copper is made to predominate, and sometimes the acetate.

The following recipes for reserves are given by M. Vitalis:

1. Sulphate of copper Acetate of copper

Gum.

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20 pounds

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The thickening is always made with pipe clay. To make a sky-blue on a dark blue.—1. Dye the cloth of a sky-blue; 2. Apply the usual reserve; 3. Pass the cloth through a strong blue vat. Brighten in a bath, feebly acidulated with oil of vitriol (or muriatic acid), to carry off the particles of lime suspended in the vat. Wash and dry.

Sky-blue, dark-blue, and white.—1. Apply the reserve; 2. Dye sky-blue; 3. Apply the reserve anew; 4. Pass through a blue vat of sufficient strength.

Deep blue, sky-blue, green, yellow, and white.— 1. Print on the reserve; 2. Pass through a weak vat, giving two or three dips; dry, brighten with very dilute sulphuric acid, wash, dry again; 3. Print on once more the common reserve paste; 4. Dye in a stronger vat than the above, till the blue be sufficiently deep; dry, brighten as before, wash and dry; 5. Print on the red mordant, and dry; 6. Give the weld or quercitron. The mordant applied to the white spots, and to the pale blue (petit blanc), affords yellow and green. The white portions that have not been touched with the mordant remain white, in like manner as the pale blue spaces, not covered by this mordant, furnish the pale blue. Reserves are also applied to silks. For example, on the handkerchiefs called foulards, the reserve is styled waxing. A mixture of tallow and resin is melted, and applied to the silk with the block; this reserve being given, the silk is dipped in the blue vat. The reserved portions, being defended from the action of the indigo, remain white, while the rest of the surface takes a fast blue.

Sky-blue, red, and white.-1. Apply the usual reserve; 2. Apply the red mordant, thickened with pipe-clay, and dry; pass through a weak blue vat, to obtain sky-blue; wash at the river, madder, wash, and spread out on the grass to clear the white.

Printing with discharges (par rongeant) on a mordant.-This process serves to form mourning garments, composed of a white figure on a black ground. The piece of goods is first passed through the black mordant by means of the padding or blotching machine. When this mordant is very dry (by passing, for example, over steam cylinders), the white discharge is applied, prepared with nitric, oxalic, tartaric, or citric acid, or bisulphate of potash, thickened with roasted starch (British gum). It is dried, washed, and maddered. On quitting the madder bath, the goods must be well washed, and exposed on the grass till the whites be very clear.

The portions of the cloth where the mordant has not been acted on by the discharge will take a black of a greater or less depth from the madder, while, on those places where the discharge has been applied, the mordant will be removed, and the madder color will not combine with the stuff. Exposure on the grass will carry off the loose madder. In like manner, by this process, white figures may readily be obtained on a ground of red, carmelite, violet, puce, &c. ; since it will be necessary merely to pass through the mordant of one of these colors, then to apply the white discharge, and finally to madder. To have white figures on an olive ground, weld or quercitron must be used instead of madder.

Printing with a discharge on color (dyed goods)-Suppose that the calico has been dyed in a logwood bath, mixed with iron liquor, the cloth will take a black color. If, after dyeing, it be impressed with a solution of tin, properly thickened, the ferruginous portions of the cloth touched with the discharge will be removed, and they will pass from a deep black to a very brilliant crimson.

By subjecting to the same treatment calicoes dyed of different colors and shades, determined by the different degrees of oxidizement of the iron, a multitude of varieties will be produced, either in the colors or in their shades.

By a similar operation, we may make figures of a beautiful green on goods, by dyeing them first of a pale blue in the indigo vat, passing them then through a bath of sumach and sulphate of iron, and finishing in a bath of quercitron with alum.

Here the green color produced by the indigo and the quercitron remains masked, as well as the other colors, by the oxide of iron in the sulphate, till the solution of tin be applied, which causes the other colors to disappear, and gives to those that remain a lustre which they would not otherwise have had; because the solution of tin renders the quercitron yellow more vivid, and because from this vivid yellow, associated with the blue, results a more brilliant green.

A figure of aurora color on an olive ground may be made, by passing the cloth first through a bath of sumach and sulphate of iron, then washing in an alkaline decoction of fustet, and printing on at last the solution of tin.

Let us give for an example the mode of making yellow figures on olive. The problem is reduced to find a discharge, which, in destroying the color communicated by iron, can at the same time change the color to yellow. This discharge is the thickened solution of tin. To the solution of salt of tin (muriate) a little muriatic acid is added. This is thickened with starch previously boiled, in a very thick and cold state, observing to pour in the solution in small portions, in order to ensure the thorough union of the ingredients. As soon as the piece has been impressed with this discharge, it is carried to the river to be washed, and to prevent the discharge from acting too long on the color. If the pattern required black, it would be necessary to apply it before the yellow discharge.

Calico printing by the combined methods of discharges on the mordant and on the dye.-First example. Olive, yellow, and white. 1. Pass through the olive mordant. 2. Print on the white discharge; wash and dry. 3. Weld. 4. Print on the yellow discharge.

Second example.-Bright red, and dull red; white, yellow, and black, on an olive ground. 1. Print on the red mordant. 2. Madder. 3. Pass through the olive mordant. 4. Print on the white discharge. 5. Weld. 6. Print on the yellow discharge and the topical black, and wash. The colors by discharges, though bright, are not so fast as those given by the dye-baths. If, instead of applying the yellow discharge, thickened as usual with starch, one-third more starch be employed, and a coloring of decoction

of Turkey. berries, or Brasil wood, be added, we shall obtain, in the first case, a richer yellow, and, in the second, an orange yellow.

The name of lapis lazuli is given to calicoes, which, after having been printed with reserve discharges, and different mordants, are passed in succession, first through the blue vat, and then through a madder bath. If a yellow or a green be wanted, there is given, in the sequel of the madder washing, a yellow mordant, and the goods are turned through a bath of weld or quercitron.

Suppose that we are to print on cloth a pattern into which there enter white, red, black, blue, green, and yellow. The goods being previously thoroughly whitened, we proceed as follow:

1. Apply the reserve discharge. 2. Print on the red mordant, thickened with pipe-clay. 3. Print on the black mordant, thickened in the same manner. 4. Pass the goods through a strong vat in forty-eight hours at farthest after the printing has been given. The dipping ought to be for six minutes at most at two times: between each dip, the goods must be aired for five minutes. They are then carried to the river, allowed to steep in it for an hour, and washed. 5. They are dunged. 6. Passed through bran. 7. Maddered. 8. Beetled very carefully and dried. 9. The red mordant is applied, which serves also as a yellow mordant. The pieces are now to be well cleaned. 10. They are passed through the quercitron bath, after which they are washed and finally dried. It may be proper to add that the reserve discharge is prepared by melting together hog's-lard and resin (arcanson), and, when the mixture is cool, diluting it with oil of turpentine; adding afterwards binarseniate of potash, and a little corrosive sublimate in powder. The whole, being well blended or ground together, is to be then printed on.

The lapis pattern may be put on a blue ground, a red, green, puce, &c.; whence result a great many varieties. The pattern was originally called lapis, from its resemblance to lapis lazuli. A slight reflection on the above process. will show us how the different colors are produced.

The blue is the immediate effect of the blue vat; the red and black are developed by the maddering on the respective mordants of these colors. The combination of blue with yellow on the yellow mordant gives green. The yellow results from the coloring matter of the quercitron bark fixed by the red mordant, which is, at the same time, the mordant for yellow. Finally, the white is occasioned by the white discharge of the reserve discharge.

The calico printer should be well acquainted with the nature of topical colors, or 'colors of application,' as they are sometimes called. The following are from Vitalis:

Topical or pencil blue.-Boil in sixty pints of water, for half an hour, fifteen pounds of potash, and six pounds of quicklime, in order to render the potash caustic. Then add six pounds of or piment (sulphuret of arsenic) reduced to fine power, and continue the boiling for a quarter of an hour, taking care to stir. continually with a rod. When the boiler is a little cooled, pour into

it from six to eight pounds of indigo well ground at the mill, and stir again till the indigo be well dissolved, which is discovered by a drop of the liquor, when placed on a bit of glass, appearing yellow. The bath, while still hot, is to be thickened with a pound of gum for every pot (two litres) of liquor, or with eight ounces of starch. This operation must be carefully preserved from contact of air, and only employed when its color is yellow, or at least yellowish-green. If it be come blue, the liquor is to be treated anew with some pounds of caustic potash and orpiment.

This blue application, says M. Vitalis, much used formerly, is seldom employed at the present day. Another blue, of less permanence, but more brilliant, is now preferred. It is made with Prussian blue, in the following manner :Into an earthen pot, four ounces of finely ground and sifted Prussian blue are to be put. Over this must be slowly poured, stirring all the while sufficient muriatic acid, to bring it to the consistence of syrup. The mixture is to be stirred every hour for a day, and afterwards thickened with from four to eight pots (of two litres each) of gum-water, according to the shade wanted.

Topical red.-A pound of Brasil wood is to be boiled in four litres of water for two hours; the decoction is then to be decanted and boiled down to two litres. As much red mordant must now be added as is necessary to form a fine red; and it is to be finally thickened with eight ounces of starch. The color will be more beautiful the older the decoction of Brasil wood is.

Instead of Bras wood, wood of Japan, Saint Martha, or Nicaragua (peach wood), may be used, provided their color has been refined from the dun which they contain, by the usual process with milk.

Topical yellow. This is prepared by boiling four pounds of Turkey or Avignon berries in twenty-four litres of water, which is boiled down to one-half. The clear liquor is drawn off, and a pound and a half of alum is dissolved in it. For the light yellows, it is thickened with gum; for the deep, with starch. This topical yellow does not resist soap. The following is equally fast and agreeable :

In eight pints of water, boil four pounds of quercitron bark in powder, down to one-half of the bulk. Pass through the searce, thicken with three pounds of gum, and mix in gradually, sufficiency of solution of tin to render the color of a brilliant yellow. This yellow resists vegetable acids and soap very well. When placed on a blue ground, it forms a fine green; and it may be applied by the plate or the pencil.

The best solution of tin which can be employed for this topical yellow is that made with a mixture of three ounces of muriatic acid, four ounces of nitric, and four ounces of pure water. Two ounces of grain tin are to be dissolved bit by bit in this liquor. When the solution is completed, half an ounce of sugar of lead is to be added. The mixture must then be well stirred; left to settle, and decanted. Half an ounce of the clear solution is to be taken for every pint of the yellow bath. On mixing with the yellow bath a little of the annotto bath, we have orange yellows.

Rust yellow.-This is made with acetate of iron, or the black cask. It is thickened with gum for the light yellows, and with starch for the deeper shades. Rust yellow, when applied on blue, gives a deep green, which serves for the stems of certain flowers.

Topical green. This preparation is formed by a mixture of topical blue and yellow, in which the yellow predominates considerably. The mixture must be made by little and little with the utmost care, so as to hit the wished-for shade.

Topical aurora.-A sufficient quantity of alum in solution must be added to the anotto bath; and the mixture is to be thickened with gum.

Topical black. To twelve pints of the black cask, or of pyrolignate of iron, at 4° Baumé (for salts), add four ounces of Roman vitriol dissolved in water, and a sufficient quantity of decoction of galls to form a good black. Thicken with three pounds and a half of starch, which is to be gradually worked up with a portion of the liquor. Boil, withdraw from the fire, and keep stirring, till the liquor be cool; it must then be passed through a searce or a linen cloth.

Another topical black.-In twenty-four pints of water, boil two pounds of logwood, two pounds of sumach, and eight ounces of galls, till the liquor be reduced to half its volume. Add then a pint of the black cask (or pyrolignate of iron); boil away six pints; take off the clear bath, dissolve in it two ounces of Roman vitriol, and one ounce of sal-ammoniac; after which thicken with starch, and pass through a searce before making use of the composition.

Topical violet and lilac.-In thirty pints of water boil six pounds of logwood, ground or in chips, till ten pints be evaporated; decant the clear, and dissolve in it one ounce of alum for every pint of liquor. The deep violets are thickened with starch, and the light violets with gum, which is to be dissolved in the cold. This color changes readily, for which reason it should be prepared only as wanted; and be immediately put to use.

In the manufacture of printed calicoes, colors are obtained from madder, which result from the mixture of red and black. For mordants, mixtures in different proportions, of acetate of iron and acetate of alumina, are employed.

One

By printing on a mordant, composed of equal parts of oxidised acetate of iron (black bouillon) and acetate of alumina, both concentrated, a deep mordoré is obtained with madder. part of acetate of iron, and two of acetate of alumina, afford a less sombre mordoré, inclining towards puce-colored. On augmenting the quantity of acetate of alumina, the shade approaches more and more to red; and, on introducing, at last, only one-twelfth of acetate of iron, an amaranth color is obtained. If, on the contrary, the proportion of acetate of iron be increased, browns are produced.

This color is that which requires most madder. It may be boiled longer than for the reds, but not so long as for the violets, because, as the portion of the coloring matter which is combined with the alumina does not stand a prolonged ebullition so well as that which has the oxide of iron for a mordant, the shade is degraded, and

there is obtained only a poor and unequal color, instead of a substantial and well raised one. Great care should also be taken to put into the bath a sufficient quantity of madder, so as to saturate all the mordant; otherwise a uniform color can never be obtained, for the bath becomes exhausted, and some parts of the cloth would be saturated before other parts had been able to assume the proper shade. For conducting the operation properly, and for completely saturating the mordant, the maddering should be given at two times. The bath is scarcely suffered to boil the first time, and, from the hue that the cloth has taken, the quantity of madder to be employed at the second maddering may be determined. When the cloth is to have, besides the mordoré, fainter colors, they should not be printed on till after the first maddering, because the heat of the bath in the double maddering would degrade them. The mordorés have a more agreeable hue, when, previous to maddering, they have been dyed with nearly half the quantity of weld or quercitron which would have been used had they been dyed with these substances alone. The mordants for mordoré and puce afford, with both these substances, the shades of olive, bronze, terre d'Egypte, &c. In this case, it is sufficient for restoring the white, to pass through bran on their quitting the boiler, and to expose them for about eight days on the grass, lifting them once in this interval in order to wash and beetle them. The color has more lustre when, before drying the cloth, we pass it through water acidulated so slightly with sulphuric acid as to be hardly perceptible to the taste.

The following example of a spirit red directly applied in calico printing is valuable:-Prepare an aqua regia, by dissolving two ounces of sal ammoniac in one pound of nitrous acid, specific gravity 1-25. To this add two ounces of fine grain tin; decant it carefully off the sediment, and dilute it with one-fourth its weight of pure or distilled water.

To one gallon of water add one pound of cochineal, ground as fine as flour; boil half an hour; then add two ounces of finely pulverised gum dragon (tragacanth), and two ounces of cream of tartar; and stir the whole till it is dissolved. When the liquor is cool, add one measure of the preceding solution of tin to two of the cochineal liquor, and incorporate well by stirring. Apply this with the pencil or block; suffer it to remain on the cloth six or eight hours; then rinse off in spring water. This color will be a bright and beautiful scarlet.

Boil twelve pounds of Brasil chips during an hour, in as much water as will cover them. Draw off the decoction, pour on fresh water, and boil as before. Add the two liquors together, and evaporate slowly down to one gallon. To the decoction, while warm, add four ounces of sal ammoniac, and as much gum dragon or senegal as will thicken it for the work required. When cool, add one of the solutions of tin above described to four, six, or eight, of the Brasil liquor, according to the color wanted. Suffer it to remain for eighteen or twenty hours on the cloth; then rinse off in spring water as before. The color will be a pale and delicate pink. If

it be required deeper, the decoction must be made stronger, and used in the proportion of three or four to one of the solution of tin. Nicaragua or peach wood, though not so rich in coloring matter as Brasil, yields a color, however, which is, if possible, more delicate and beautiful.

A process in calico printing, of peculiar elegance, with an alkaline solution of alumina, was invented by James Thomson, esq., of Primrose Hill, near Clithero. Its effect was to produce a fast green, by the mixture of a yellow mordant with the common solution of indigo in caustic potash, through the intervention of orpiment. This, as is obvious, could not be done with any acid solution of alumina. Mr. Thomson first formed a solution of that earth in potash, mixed this with the solution of indigo, and applied the mixture, properly thickened, to the cloth. But as, in the ordinary dunging operation, the alkali would naturally wash away with it the greater part of the alumina, the goods before being dunged were passed through a solution of sal ammoniac. It is easy to perceive the rationale of what takes place. The potash on the cloth combines with the muriatic acid of the sal ammonia, and, as the two substances set free (the alumina and ammonia) have no tendency to combine, the former remains precipitated on the cloth at its points of application. It obtained currently, but very improperly, the name of Warwick's green, because Dr. Warwick made and sold the solution of aluminated potash to the printers.

Acetate of alumina is now most frequently made for the calico printers, by dissolving alum in a solution of crude acetate of lime (pyrolignite); a gallon of the acetate, of specific gravity 1050, or 1·060, being used with two pounds and three quarters of alum. A sulphate of lime is formed, which precipitates, while an acetate of alumina mixed with some alum floats above. The specific gravity of this liquid is usually about 1.080. The acetate of alumina employed as a mordant for chintzes is still commonly made by the mutual decomposition of alum and acetate of lead. Fifteen parts of alum are equivalent to about twenty-four of acetate.

The maddering of printed goods requires pains and precautions, which long practice alone can teach. The causes which make their effects to vary are too numerous for us to point them all out here. The quantity of madder employed, the duration of the maddering, the manner of managing the fire, are, along with the dunging, the circumstances which have most influence; and they cannot be subjected to any rule, because they must differ more or less in almost every process.

It is plain that all these operations have for their objects, 1st, to remove the mordant uncombined with the cloth; 2dly, to fix the coloring matter; 3dly, to carry off, by the action of the air and bran, the dun coloring matter which is mixed with the madder, as well as the color which covers the parts of the cloth not impregnated with mordant.

The cloths intended for printing ought to be very carefully bleached. The more perfect the

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