[8]It is necessary that the student should not confound the termsprimitivecolours here with theprismaticorprimarycolours, for the discovery of which we are indebted to Sir Isaac Newton. Seethe Introductory Chapter.
[8]It is necessary that the student should not confound the termsprimitivecolours here with theprismaticorprimarycolours, for the discovery of which we are indebted to Sir Isaac Newton. Seethe Introductory Chapter.
To dye silk black for velvets—To dye silk black, London process—On dyeing cotton black at Rouen—To dye cotton black, London process—For dyeing black, particularly cotton velvets, at Manchester—On dyeing silk and cotton black, with a blue ground—Another iron liquor—To dye cotton black, by using the preceding solution—To dye cotton violet—To dye cotton red—To dye cotton an Adrianople or Turkey red—Miscellaneous observations relative to Adrianople red.
Someof the more simple and less difficult processes of dyeing bothcottonandsilk, are described in the preceding chapters; we shall now describe those, not only for black, but for some other colours, which require more care and attention.For ungumming and boiling silk, &c. see Chap. VI.
Silk has a strong affinity for galls, and advantage is sometimes taken of this: for silk, being a valuable article, is often galled to excess, merely to increase its weight.
Cotton has a strong affinity for iron, and iron has the same forgallic acid, wherever it may be found; therefore, in sumach, alder-bark, &c., iron unites with the acid, whenever both are connected by the medium of water.Tannin, doubtless, has also some share in such dyeing processes, although what does not even now appear to be well understood.
Black,Macquerobserves, is rather difficult to be dyed upon silk; or, at least, there is reason to think so, from the numberless experiments which have been found necessary to the attainment of a good black, as well as from the multitude of heterogeneous ingredients which Macquer admitted into the composition of his various processes for this dye, some of which consisted of arsenic, corrosive sublimate, litharge, antimony, plumbago, and about ten other ingredients! we shall not, therefore, detail such preposterous mixtures; one, however, we may just put down by way of showing what the art was in Macquer's time.
Take twenty quarts of strong vinegar, one pound of black nut galls pounded, and five pounds of iron filings; these ingredients are to be mixed in one vessel.
The silk should be ungummed by boiling it four hours with a quarter of its weight of white soap, and afterwards to be well cleared from the soap.
Take, for every hundred pounds of silk, twenty pounds of galls in powder, and boiled one hour; two poundsof sulphate of iron; twelve pounds of iron filings; and twenty pounds of gum arabic or senegal.
This process is very simple: here are the gallic acid and tannin of the galls, and the iron of the sulphate and the filings. But we must proceed to a more modern process.
Take of wove silk,twilled sarsenet, one hundred and fifty yards. Boil, for three hours, of alder bark one bushel and a half; of logwood fourteen pounds; and of iron filings one pound. Then let the fire be damped; dissolve four ounces of sulphate of copper in water; wet out the silk in hot water; after which put the solution of sulphate of copper into the liquor and stir it only; then put the silk into the copper, and work it from end to end four times; after which take it out in the air; now put it in again and work it as before; take it out again and let it be aired on the floor, opening it from time to time till it is cold; repeat the same thing twice more, in allfour times. This is termed four wets. While the last wet is cooling and airing, dissolve and put into the copper three pounds of sulphate of iron, and then give the silk two more wets, which make the number of wets six. The drugs are now left to boil as much as they will during the night, being left so to do, because in a large business, this part of the process would close the day's work.
The next morning give the silk four or five wets more, and leave it in the copper all the following night, observingwhen it is left in, and always when it is worked in, that the heat, must be considerably under the boiling point, and the silk kept covered by the liquor: forif any part be exposed to the air it will be marked.
Take one hundred quarts of sour wine, bad vinegar, or small beer; put to either of these twenty-five pounds of old iron hoops rusted by the air or dew; twelve pounds of rye meal or coarse bran; put the whole into a copper and heat it rather more than blood warm. In the summer it would do exposed to the sun and air with a porous cloth over it, to let in the air, but keep out dirt, &c.; the older this solution is the better; but it should be at leasttwo months old.
Cotton skeins are galled by being worked in a solution of galls; alumed and then dyed in weld liquor; this in the result is yellow; they are then passed through a decoction of logwood, and after that of sulphate of iron, a quarter of a pound to every pound of cotton; they are then dyed in madder, half a pound to every pound of cotton.
We cannot recommend this process, although we give it, as much better methods are now known.
Cotton cambric piece-goods are passed through a blotching machine to receive a mordant of acetate of iron,and galled slightly; sumach is used instead when galls are dear; the cotton is then passed through logwood, or logwood and fustic, and then through sumach; so that it is possible thus to give them the mordant sufficiently in proportion to the iron liquor at first; proceed as in dyeing afterwards, at a heat approaching boiling or even boiling. You may now proceed by adding first the galling or sumach slightly; afterwards the logwood, &c.; and then the remainder of the galling or sumach may be used to finish it; and thus dye the goods black by the quickest possible process.
It should be observed respecting the last process and the process which precedes it, that in dyeing black alum is inimical to the colour. Therefore D'Apligny's is not now esteemed. Alum for black is as improper, as it is proper and essential for red and yellow.
In regard to giving the acetate of iron for black at once, as the second, orLondonprocess directs, it may be done by having the proportions full; byfullis meant that the mordant should be full enough; then, after the slight galling, as directed in giving the logwood and alder bark decoction, or logwood and fustic, be sure to have that decoction strong enough. This might be called the ground; and the most perfect judgment might be formed of it by having a part of a piece, or one piece of a batch dried in the stove: for, according to the fullness of the ground, so will the black be rich and perfect or otherwise.
The alder bark and fustic are used only to prevent the hue of the logwood from being predominant. If the ground be a full and rich brown, the second full gallingor sumaching will bring it to a full and rich black; but, if the ground be poor, these processes will cut or destroy the ground, and the black will be foxy, nasty, and poor; and not only so, but the material dyed will soon wear rotten, because having an over-dose of iron, the iron will tend to decompose the cotton. Therefore the following process is most esteemed.
In a large dye-house where much business is done, a great many wine-pipes or other large tubs, or any substitutes are arranged in an appropriate place. Into these are put old iron hoops, rusted in the air, and cut into short pieces; a layer of the iron pieces and a layer of the alder bark, again a layer of iron and a layer of the bark, and so on in succession from the bottom to the top. When the pipes are all thus filled, water is poured into them till they are filled up; they remain in this state for six weeks or two months according to the season, whether summer or winter.
The same process will do for any other cotton goods as well as velvets, such as calicoes, cambric, and jaconot muslins, cotton in the skein, &c.
In some cases there are persons who pass the goods through theliquorof the aforesaid black vat. The colour of this liquor when it is fit for use is purplish, particularly after being once used and returned to the vat again, which it always is. Others begin by passing the goods through a decoction of logwood and sumach,then through sulphate of iron, then wash off through logwood only; then through sulphate of iron; always washing off from this last; the goods are then dried, and this is called thefirst time of saddening.
They are next passed through logwood, then through sulphate of iron, then washed off, then again through logwood, then sulphate of iron, and then washed off; and then dried. This is called thesecond time of saddening.
Supposing the goods to consist of a hundred or a thousand pieces, after drying the second time they are brought in lots to the foreman for examination, and assorted into lots one, two, and three. All that is fit for lot one is full enough and has ground enough, and is of a rich full-bodied brown, ready for galling orsumaching: sumach being the substitute for galls, this process is termed in the dye-house,macing. Lot two is not full enough, and must pass through logwood, then sulphate of iron, and then be washed off. Lot three is still more deficient; this must be passed through logwood and the sulphate of iron twice and then washed off, and both lots two and three dried again.
Lot one is now to be sumached for thefirsttime: that is, passed through a decoction of sumach, then through sulphate of iron, and then washed off: if the decoction of sumach be kept up strong after all of them are once sumached, they may be dried. Lots two and three, when they are dry, are also to be sumached the same as lot one, and dried.
As soon as any of them are dry they are ready to be sumached thesecondtime by passing them through thedecoction as before; but instead of sulphate of iron, some of the alder bark andiron liquorare used; or as we shall term it, theliquor of the black vat. They are then to be washed off and dried. If the black liquor and the sumaching be powerful, some of the goods will be finished when dry. Such are examined by the foreman; those which are not finished must go through the last process again. The finished goods are well and repeatedly washed off in fresh clear soft water two or three times and then dried.
Thecambric muslinsare sent to be calendered to imitate silk sarsenets.
Book-muslinsmust be sent to the muslin dressers, except where, in some cases, they sarsenet and dry their own goods.
By the above method the ground is secured, and so is the black, and also the strength of the goods.
It is remarkable, that although an indigo ground for wool enriches the black, yet for silk and cotton it is not generally considered necessary. Latterly, however, we believe the dyers of black on cotton do first give it an indigo ground before the black is given. This is, nevertheless, not a new method, for D'Apligny describes the process in his Art of Dyeing,for linen and cotton yarns; these are first dyed sky-blue in the vat, then wrung out and set to dry. They are galled in the proportion of one part galls to four of yarn, being left twenty-four hours in the gall liquor, wrung out anew, and set to dry: aboutten pints of iron liquor to every pound of yarn are then poured into a tub, in this the yarn is turned on sticks, and worked with the hand for a quarter of an hour, it is then wrung out and aired. This operation is twice repeated, adding each time a new dose of the iron liquor; the yarn is aired once more, then wrung out, well washed, and dried. To complete the dyeing of the yarn a weight of alder-bark equal to that of the yarn is boiled with a sufficient quantity of water for an hour; to this is added one half of the bath which has served for the galling and sumach. The whole is boiled for two hours. When cold the yarn is put in and worked, aired occasionally, and then left in the bath for twenty-four hours, when it is wrung out and dried. To complete it, it is steeped and worked in the residue of a bath of weld, to which a little logwood is added; it is then taken out, wrung, and immediately passed through a tub of warm water, into which one part of olive oil to sixteen of yarn has been poured. It is finally wrung out and dried. SeeUre'sBerthollet, vol. ii. page 18.
Although we have described aniron liquorin a preceding section, it may be useful to give the following process for another here. Fill a cast-iron boiler with pyrolignous acid, add to it old iron well oxidized, and boil. The solution of the oxide will take place rapidly. When the iron grows clean, and the solution black as ink, throw the whole into a cask, to be employed as occasion shall require.
Prepare the cotton as usual, by giving it a blue ground; gall it, and pass it through a bath of the solution of pyrolignite of iron diluted with lukewarm water. Renew the gallings and the passings through the bath of pyrolignite of iron till a deep and brilliant black is obtained. Finish by passing the cotton through olive oil thus: throw on some lukewarm water a little olive oil, pass the cotton through it; the cotton absorbs the oil, but it must be worked a long time in the bath to diffuse the oil equally. Dry in the shade. The cotton is now a perfect and very durable black.
Every time the bath of pyrolignite is used, what remains must be thrown away; the old baths are never added to the cask.
The application of oil, which heightens the black, and imparts softness to the stuffs, is given to such articles as cotton velvet by means of brushes, which are slightly imbued with it.Berthollet.
We may add here, that an iron liquor calledtar-iron liquor, prepared from the acid obtained from tar, (the acetic acid we presume) is now well known in commerce, but we have not room, nor does it appear necessary, to describe the method of making it; it is much used in preparing mordants for black and other colours by the dyers and printers of silk. This iron liquor may be obtained of Blake, North Street, Back Church Lane, St. George's in the East, London. SeeM'Kernan.
Pass the skeins through the black vat and dry them, then pass them through a decoction of galls and dry them again, then through a decoction of logwood, then of alum and verdigris, washed off, and dried.
Or thus: by the black vat liquor, that is, the liquor of old iron and alder bark in some cases. Let the vat liquor be prepared from the iron hoops, vinegar, rye, or coarse bran, described in page 108. By this liquor it is easy to procure all the violet shades from the pansy flower up to the lilac and violet.
The goods must be first blue-vatted and dried, then galled and dried, then passed through the iron liquor, then maddered, then washed off, and dried; the liquor must always be kept much below a boiling heat, as this heat makes the colour obtained from madder brown: whatever drugs require boiling must be prepared by a decoction previously made.
For some shades sulphate of copper is used; for others verdigris, saltpetre, and alum.
To dye to the pattern the preparations should be always of one given strength, and all solutions of mordants the same. The time of working the goods in the dye must be regulated by the fulness or lightness of the pattern; and the quantities of the various drugs, &c. used much or little accordingly, reserving patterns of processes, with the particulars of such processes noted down. In proportion to the number of these upon record, and with strict attention to the subject, a good pattern dyer is formed. Time and practice are, however,absolutely necessary, with a delight in the business: for without a pleasure in dyeing no one can become a good or an eminent dyer. In many of the branches of this art there are, it is true, labour and pains in abundance; but there is also a portion, and that not a small one, of pleasure in others, which will counterbalance the care, anxiety, labour, and fatigue inseparable from this useful and important occupation, and which so strikingly exhibits the science and ingenuity of man.
If the cotton skein has not been cleansed since it was spun it must be cleansed by being boiled in a solution of potash, one ounce of which, if good, to a pail of water may be enough, or more than enough. The cotton must be put into bags when boiled, then washed off and passed through clean water, scoured with a little sulphuric acid, and then washed off again; then galled, washed off, and dried. The galls should be white galls: for twenty pounds of cotton five pounds of bruised galls are boiled in about one hundred and twenty quarts of water for two hours.
After galling, the cotton must be alumed: four ounces of Roche alum for every pound of cotton. When alumed it must be washed off and dried.
The cotton is now to be dyed in a copper containing six pounds and a quarter of best crop madder, with a sufficiency of water. The heat is kept under that of boiling for three quarters of an hour. After being aired, washed, &c. it is put in, worked, and boiled for twelveor fifteen minutes. Some dye it again two days after, because the longer to a certain degree between aluming, dyeing, and drying, and between one dyeing and another, the better. The second time of dyeing eight ounces of madder are used for every pound of cotton. Some dyers gall it twice, and consequently dry it as often, then dye it at once in the madder, having a proportion accordingly. This is a red full-bodied colour.
For one hundred pounds of unbleached cotton, take the following articles and pursue the described processes.
Lixivium No. 1. Dissolve one hundred and fifty pounds of alicant soda, (barilla) in three hundred quarts of river water. There must be no more water than enough to dissolve the salt. An egg must float on it or it will not be strong enough.
Lixivium No. 2. One hundred and fifty pounds of fresh wood ashes, and three hundred quarts of water.
Lixivium No. 3. Seventy-five pounds of quicklime, and three hundred quarts of water.
The cotton is to be boiled three hours in a liquor composed of equal parts of each of the above solutions, taken from them when clear and in a settled state. The liquor must be replenished occasionally, so that it shall always cover the cotton during the whole time it is boiling; after which it must be taken out, washed, and dried in the air.
Into one hundred and thirty quarts of a mixture consisting of equal parts of the above three lixiviums, puttwenty five pounds of sheep's dung and part of the intestinal liquor, previously well mixed by means of a wooden pestle, and the whole strained through a hair sieve. Then twelve pounds and a half of good olive oil is poured into the mixture, when it instantly forms a soapy liquor.
Into this liquor the cotton should be worked hank by hank, often stirring it; the cotton, after all the hanks have been worked separately first, is then left in the liquor for twelve hours; it is then taken out, lightly wrung and dried. The liquor is put by for brightening. This process is repeated three times during the working; and by the time the solution is all worked four hundred quarts might be used, but that will not injure the clear of it from being applied in brightening; and it must be reserved for that purpose.
When the cotton has been three times dipped in this soapy water, and three times dyed, the same process is repeated, except that the sheep's dung is left out; the liquor is also preserved for brightening. The cotton, having gone through these processes, should be as white as if it had been bleached.
When dry it is to be galled, using a quarter of a pound of galls to every pound of cotton; after this it is dried, then take six ounces of alum for the first aluming; it is then to be dried again, and to hang three or four days in the air, and then, when dry, to be alumed again; four ounces of alum, and four of the lixivium may be added to the last alum water.
The madder used for this red is calledlizary, which furnishes a dye incomparably finer than that producedby any other madder. Of lizary madder, therefore, take two pounds for every pound of cotton, and twenty pounds of liquid sheep's blood well mixed with the water in the copper before the madder is put in. The butcher should stir the blood to prevent its coagulating; the copper should be carefully skimmed; the madder should not boil, but be brought during the process from blood-heat to within a few degrees of the boiling point: if it boil at last, as some prefer it, it should only be for a few minutes.
In order to brighten the colour, the cotton is dipped in a lixivium of fresh wood ashes, and five pounds ofwhitesoap: yellow or mottled soap is improper. When the cotton has been well worked in this liquor, it is, with the liquor itself, put into a copper sufficiently large to hold it with some addition of water, and made to boil over a slow fire, for three, four, or more hours. The liquor must be covered with coarse white linen cloths, to keep as much steam in as possible.
Some of the skeins of cotton must be taken out from time to time, and washed perfectly; when the red is judged perfect and sufficiently bright, the fire is withdrawn.
If instead of the wood-ash lixivium and soap, the two reserved liquors and soap are used, the red will be much brighter than the finest Adrianople carnation.
In regard to the above processes, we may observe, that those given for Adrianople red inUre's Berthollet, aremore numerous, being regularly numbered to theseventeenth, or last operation calledbrightening. After a careful attention to those processes we see no reason to alter our own, yet we nevertheless advise the dyer to become acquainted with what is stated in that work, many details being there given for which we have not room, particularly for makingdifferent shadesof the colour. We add, however the following from vol. ii. p. 140.
"Cotton dyed red, may, moreover, be made to pass through all the shades, down to the palest orange, thus: pure nitric acid is diluted with two-fifths of water; chips of tin are oxidized in it till the liquor grows opal; the solution is employed at different strengths; the colour varies according to the concentration of the solution: when it is strong, shades are obtained which have some relation to those of scarlet.
"In general, when brilliant colours are desired, we must not charge them too much with oil; we must give feeble leys long repeated, charge little with alum, employ the best madders, and, at last, brighten powerfully without sparing soap."
We have directedgoodolive oil; but M.Vitalisdirects fat oil, (gallipoli) to be used in the processes for dyeing Adrianople red, and Berthollet says, it must not be afine oil, but one containing a strong portion of the extractive principle.
A factory for dyeing this red was first established in this country in 1790, by M.Papillon, who obtained a premium from the Commissioners and Trustees for Manufactures in Scotland, for communicating the details of it on condition it should not be divulged for a term of years,during whichM. Papillonwas to have the sole use of his secret. This term being expired the process was published. See vol. xviii. ofTilloch's Magazine.
M.Vitalis, (in his work on Dyeing published in 1823) has given, at length, themode of dyeing Turkey red at Rouen. It differs in many particulars from Berthollet and others. We learn from him that two systems for imparting this colour are in use at Rouen. The first is called thegrey coursefrom the cotton being subjected to the maddering immediately after it has received the oily preparations, and the mordants of galls and alum which give it agreycolour. Theyellow course, is so called from the cotton, after having received a first time the oily preparations, as well as the mordants of galls and alum,notbeing exposed to the maddering till it has passed a second time through the same preparations, and the same mordants which give ita yellowcolour. This second manner of working the Turkey red is called, in the dye-house,remounting on the galls. Dr.Ure, in a note to Berthollet, vol. ii. p. 378, has detailed these two courses, and made, besides many valuable observations on them, and the dyeing of Adrianople red generally, for which we must refer to the work, as our limits prevent the possibility of any further notice of them here, except to add, that aprocess for dyeing cotton of a smoke red; and another fordyeing cotton a cherry red, is well deserving the attention of the dyer.
In regard to thebloodused in dyeing Adrianople red, Dr. Ure decidedly affirms, that "it adds no colouring matter to the madder in the dyeing operation;" in this he is countenanced by the observations of Chaptal, seeBerthollet, vol. ii. p. 141. "To the use of blood in the madder copper," says Dr. Ure, "I attribute nothing, as from the rancid and putrid state in which I have seen it used, were it not for the prejudice of the operator, it might be safely dispensed with." A very eminent calico manufacturer, whom Dr. Ure consulted, assured him, that in the Turkey red process the only essential mordants were oil and alumina; and that bright and fast reds, equal to any produced by the complicated processes of sheep's dung, galls and blood may be obtained without those articles.
We make no comments on these observations, but leave them to the good sense and intelligence of the dyer: they deserve the utmost attention.
Linen yarntakes a colour almost as brilliant as that of cotton, but it must be passed through a double number of oils and leys. The latter must even be very strong, otherwise the oil flows out at the surface. The greatest attention must be bestowed on the scouring out first: for the yarn mingles and entangles by the heat to such a degree, that it sometimes can be neither dipped nor unravelled.
It should be mentioned that the large dyers of Adrianople red, now obtain their soda for lixivium No. 1, by using common salt in solution, to which is added a solution of pearl-ashes. On boiling these together a muriate of potash is formed, which is taken out of the liquor with a skimmer; acarbonate of sodaremains dissolved in the liquor, and is, of course, applied to the same purpose as, and at a much cheaper rate than, the Alicant soda.
To dye skein cotton yellow—On dyeing and re-dyeing cotton furniture yellow—To dye cotton skein a duck's wing green and olive—Of browns, maroons, coffee colours, &c.—Observations on silk—On ungumming and boiling silk—Whitening—Sulphuring—On aluming silk—Skein silk for yellow—Preparation of annatto, for aurora, orange, moidore, gold colour, and chamois—To dye silk aurora or orange—To dye moidore—Process for orange—To dye silk poppy or coquelicot—A cheaper poppy with annatto and Brazil wood—On dyeing silk a fine crimson—Composition for dyeing silk scarlet or crimson, with cochineal—Another process for crimson—Crimson by Brazil wood—Of fine violet—Observations on crimson and scarlet upon silk—On dyeing silk green—On olives—On dyeing silk grey—Nut-Grey—Black greys—Iron greys—On dyeing silk of a Prussian blue colour—Chromate of lead for yellow on silk or cotton—Conclusion.
Wehave in several preceding chapters treated of bothcottonandsilk; we shall here treat of certain processes andcolours relative to both these substances, which are most conveniently arranged in this chapter.
The simpler processes forcottonwill be found in thesecondchapter, the more complex in thefifth; the simpler processes forsilkare given in thethirdchapter, the more complex in thefifth; the remaining processes for both in the present chapter, will conclude the work.
The same operations as those in the first common red dye are to be used here; to one pound of cotton four ounces of roche alum, and from one to four pounds of weld.
When dyed the cotton is to be worked in hot, but not boiling, liquor, consisting of four ounces of sulphate of copper to every pound of cotton; it is then to be boiled for three hours in a solution containing four ounces of soap to every pound of cotton.
When a dark orjonquil colouris wanted, no alum is used; of weld take two pounds and a half, very little verdigris, or a little alum in its stead, but nothing else. For brightening, however, boiling in a solution of soap is in all cases necessary.
If the furniture, such as rough or finished cotton or cambric, intended for yellow linings for bed or window curtains, be in a perfectly bleached state, which is now generally the case, according to the number of thepieces, so must the size of the copper be to boil the weld in for the yellow dye. A small copper holding four or five pails would do for three pieces of twenty eight yards each. The weld may be purchased by the half bundle, the bundle, or the load. Half a bundle would be enough for the above quantity of cotton, if a moderate yellow is wanted. The weld must be increased or decreased according as the pattern approaches a straw, a canary, a lemon, or towards a gold colour or orange.
The weld must be boiled about twenty minutes, the liquor then strained off into a proper tub, and the weld boiled again. While the boilings are going on, three tubs, being wine pipes cut in two, must be got ready and made particularly clean, being also previously seasoned for the work. One is to receive the boiled weld with some cold water to regulate it to the heat which the hand will bear; the other is for water, and as much alum liquor as will colour it and make it taste strong; and the third is to contain clear water to wash the furniture off.
Whatever yellow is infashion(or indeed any fashionable colour,) has commonly afashionable name. But if the dyer can, by his experience, proportion his drugs to the weakest, and from that to the strongest shade, let the name be what it may, after he has a set of patterns of his own dyeing, he will see, upon the first sight of any colour, how to set about it.
In the present instance let the pattern be a moderately pale colour of yellow; then put all the first boiling of the weld in the first tub, and cool down as above directed. Two or three persons should then work the pieces quick from end to end by the selvages, that they may beeven, two may do this; one of whom must be an expeditious hand to work them and keep them even. When they have been edged over six or seven times, they are to be folded out upon a board laid over the tub, and wrung as dry as possible by two persons. When they are all out, they are passed in the same manner through the tub of alum, and, after six or seven turns, they are to be taken out of the alum liquor, wrung as before, and then washed off.
By this time the second weld liquor will be boiled; some of the first must be thrown away, and the second weld liquor added in its place. The goods are then passed through as before, and wrung out; the alum liquor being strengthened, they are passed through it, wrung out as before, and then washed off: the water in the wash tub having been changed.
In some instances verdigris is used instead of alum; and in other cases it is used in addition to the alum. For some shades old fustic is used instead of weld, and sulphate of copper instead of verdigris.
The alum solution, and the sulphate of copper, and the verdigris, or acetate of copper should be always ready. It is necessary to have a tub for each, in size proportioned to the work to be done; but larger for the alum than for the other two.
Sulphate of iron is also used in some dark greys, browns, slates, and in all blacks; this will require a tub as large or larger than that for alum.
When the yellows are dyed and wrung as dry as possible, they should be taken into a close room or stove to dry, particularly inLondon, because of the smoke,especially in winter. A German, or other stove, should be placed in the room, the size of which, as well as the number of the stoves, must be regulated by the quantity of the work. When the goods are dry they must be sent to the callenderers, if directed to be callendered; but the general and better way is to stiffen them with starch after they are dyed, and before they are dry; and when dry they should be sent to the glazers, instead of the callenderers, except when both branches are carried on by the same person.
When furniture, originally yellow, has become faded, it may be re-dyed thus: In this case it should be dyed rather of a fuller shade than the original. A large flat tub, such as described above, is to be filled three parts full of water, to which sufficient sulphuric acid must be added to make it taste strongly sour. After being well stirred, the pieces are to be put in, and worked in this sour liquor; and the yellow dye in consequence is stripped off. If the acid liquor be not strong enough more acid must be added, with the precaution of well mixing it with the water, and the goods must be passed through the liquor again: by these means the yellow is discharged. They are then to be taken out on a board upon the tub and wrung by two persons; then to be washed off and wrung, washed and wrung again, when they are fit to be dyed.
It is still to be remembered that any faded or worn out colour, or that goods more or less decayed, seldom become so bright as the colour which a new piece of goods receives from the same dye.
Some cloths for re-dyeing require the application ofoxymuriate or chloride of lime to discharge their colours, particularly when madder or galls, &c. form the constituent parts of the dye. In this case if ableacherbe near it might be best to let him perform the process with the oxymuriate of lime; not only from the pernicious nature, but also from the expense of it, which, unless the business be upon a large scale, will not pay the dyer for his trouble.
However, if the dyer thinks proper to perform this operation, then the oxymuriate of lime or bleacher's ashes, &c. may be obtained at the dry salters and dissolved in a cask, and the clear liquor used in proportion to the quantity of goods, the colour of which is intended to be discharged, which, when done, should be washed off in two waters at least before they are dyed.
This is performed by a blue ground, next galling, dipping in the black vat, then in the weld dye, then in verdigris, remembering to wash off previously to performing each process.
Oliveis to be performed with weld or old fustic, verdigris, and Brazil wood.
It would answer little purpose to enlarge this treatise with a detail of all the possible methods of producing the various shades of these several colours, the wholeconsisting in the use of galls, verdigris, sulphate of copper, weld, and madder.
By welding a stuff previously maddered forredyou may produce agoldcolour; and by dipping the same red in a blue vat you obtain aplumcolour.
Silk, as it is obtained from the cocoons of the worm, is generally of an orange or yellow colour, more or less dark; in the South of France it is generally very dark: its natural shade is unfavourable to almost all other colours. It is also imbued with a kind of varnish or gum, which makes it stiff and hard; this stiffness is improper in the fabrication of most silk stuff, it is thereforeungummed, as it is called, by the following processes.
Observe, that throughout the following processes for silkwhitesoap is directed to be used; and, generally speaking, we believe it will be found the best, more especially for the more delicate operations. YetMr. M'Kernan, in his process for ungumming silk, directs yellow soap and soft soap in equal parts, and of the same weight as the silk to be used: he adds, however, that different sorts of silk require more or less soap; the best rule he finds, nevertheless, isthe same weight of soap as of silk: and he says also, that yellow soap and soft soap of the best quality he finds the best for this purpose.
The silk is divided into hanks, each hank is tied witha string, several of these are tied together (a handful of them) by putting a piece of string through each separate skein, and tying the piece of string in a long tie to slip easily when they are wanted to be untied.
A liquor is prepared of thirty pounds ofwhitesoap to a hundred pounds of silk; the soap is cut into small pieces and boiled in water, when it is dissolved the fire is damped.
While the liquor is preparing the skeins of silk are put on rods; as soon as the soap liquor becomes a little below boiling heat (for it should not boil, as boiling would tangle the silk) the silk is to be put into it in an oblong copper, being nearly full; it is to remain in the liquor till its gummy matter has left it, which will be seen by its whiteness and flexibility. It is then turned end for end on the rods, that the part above the liquor may undergo the same operation. As soon as this is accomplished the silk is taken out of the copper, the hanks which were first turned being soonest done.
The hanks are now to be taken from the rods to the peg, disentangled, and nine or ten of them put on one cord, this cord passing through the string that tied each hank. When the whole is corded it is put into pockets of coarse strong white linen fifteen inches wide and five feet long, closed at each end and on one side; when the silk is put in, the pocket is sewed all along the other side with packthread, and fastened with a knot; four pockets will hold the whole hundred pounds.
The pockets being thus ready another liquor is prepared like the first. When ready, and the boiling checked with cold water, the pockets are put in andboiled well for a quarter of an hour, checking with cold water in order to prevent its boiling over; it is necessary also to turn the bags about often with a pole, or rather let two persons have a pole each for this purpose. This operation is called boiling.
In addition to the processes of boiling with soap, as above directed,Mr. M'Kernanrecommends that the silk should be winched through a copper of water at the heat of 160°, having two pounds of soda (barilla) dissolved in it, then winch or wash in water, and wring and dry.
In the boiling of silks for common colours twenty pounds of soap will do for a hundred weight of silk; but, as in this case, the silk is not ungummed, it should boil for three hours and a half, adding water to supply the evaporation.
The silks intended for the greatest degree of white, either to remain white, or for the fabrication of white stuff, are boiled twice in soap and water; those that are to be dyed of different colours are boiled but once, and with a smaller quantity of soap, because the little remaining redness is by no means prejudicial to many colours. Different quantities of soap are, however, necessary for different colours.
Silk designed for blue, iron grey, brimstone, or any other colour requiring a very white ground, should be done according to the preceding process, and have thirty pounds of soap.
When the silk is boiled it is taken out of the copper by two men with poles, and placed in a clean barrow; they are then taken to a long shallow trough, from which the water may run away, the pockets are opened, andthe silks examined; such as have yellow or lemon colour spots remaining are boiled again for some time, till the spots are removed. After unpocketing, the whole is dressed on the pegs.
Silk loses from twenty-five to twenty-eight per cent. of its weight in ungumming and whitening. The bags of silk should never be suffered to lie long together before they are emptied after being boiled, as their doing so would make the silk hard.
Whitesilk, as before observed, is distinguished into five principal shades, namely,China white,India white,threadormilk white,silver white, andazure white.
The three first are prepared and boiled as has already been shewn. Silver and azure white in the preparation or ungumming thus: take fine powdered indigo, put it into water boiling hot, when settled the liquor is calledazure.
To azure the silkit is taken from the ungumming copper after it is dressed and put into a trough of water; after it is worked, drained, and again dressed, it is ready for the
Put into a copper with thirty pails of water half a pound of soap; when it boils, and the soap dissolved, add forChina whitea littleprepared annatto, (of which hereafter.) The silk, being on rods, is now to be put into the copper and kept turning end for end without intermission till the shade is uniform. ForIndia whitea little azure is added, to give the blue shade: forthread whiteand others a little azure is also to be added.
Observe, the liquor should be very hot, but not boiling; the turnings five times repeated, by which the shade is made even. When finished it is taken out, wrung, Spread on poles to dry, and that part of it required forsulphuringmust be put upon rods or slight poles.
The hanks, being upon poles seven or eight feet from the ground, in an appropriate room, one pound and a half or two pounds of roll brimstone will sulphur a hundred weight of silk.
Put the brimstone, coarsely powdered, into an earthen pipkin with a little charcoal or small coal at bottom. Light one of the bits with a candle, which will kindle all the rest.
The room should be close, the chimney, if any, being closed up; the sulphur should burn under the silk all night. The next morning the windows should be opened to let out the smoke and admit the air, which, in summer, will be sufficient to dry the silk; but in winter, as soon as the sulphurous fumes are dissipated, the windows must be shut and a fire kindled in the stove or stoves to dry the silk.
Observe, if the room for sulphuring does not admit of openings sufficient for the dissipation of the sulphuric fumes, the work-people will be in danger of suffocation.
When the sulphur is consumed it leaves a black crust which will light the future sulphur like spirit of wine.
If, in dressing, the silk sticks together, it is not sufficiently dry.
Silk, which has been sulphured, has a rustling, which, for some things, is esteemed; but this would not do for silk to be watered. If silk, which has been sulphured is to be dyed, it must, for many colours, be unsulphured.
Silks for lace, gauze, &c. are neither boiled nor ungummed; silks which are naturally the whitest are the best for those articles. It is sufficient to dip the silks in warm water, and wring them; then sulphur them, afterwards azure them, again wring them, sulphur them a second time, or soak them in soap and water, those for whitening hot enough to bear the hand, adding azure, if necessary, and turning and re-turning the silk in this liquor.
The fine silk ofNankinrequires no whitening.
We have treated of this before at the commencement of the third chapter, but a few more observations may be useful.
The silk being first well washed and beetled, and the hanks tied loose so that every thread may take alike, should be turned and re-turned in the alum liquor and worked, cooled in it, at intervals, from morning till night, afterwards taken out, beetled, and rinsed.
The above proportion of alum will do for a hundred and fifty pounds of silk, before you need replenish it; when this is necessary add twenty-five pounds more of alum, as at first directed in Chapter III., and so continue to replenish it till it gets a bad smell. When this is thecase you may dip for browns, maroons, &c.; and afterwards throw the liquor away; the trough is then to be rinsed for a fresh liquor.
Remember always to alumcoldor you will spoil the lustre of the silk.
This is to be boiled with about twenty pounds of soap for every hundred pounds of silk. When boiled it is to be washed and alumed, and again washed, dressed, and put on the rod, seven or eight ounces to a rod, and then dipped and re-turned in the yellow liquor, in the proportion of two pounds of weld to one pound of silk.
The liquor is not to be hotter than the hand can bear while the silk is in it. The silk, when in the vessel for dyeing, should cause the liquor to float within two inches of the edge. The silk must be taken out and the liquor strengthened, if the pattern is to be very full; when full enough, one pound of pearl-ash for every twenty pounds of silk must be dissolved in some warm water; about a quarter of this liquor is put into the dye bath: take the silk out while you put in the liquor, stir the mixture well. Put in the silk and work it, turning and re-turning it as at first. After seven or eight re-turns, one of the hanks is to be taken out, wrung, and tried at the peg, and, if sufficiently full and bright, all is well; if not enough so, some more pearl-ash liquor must be added, and the silk worked as before, till the shade required is obtained.
Forjonquilit may be necessary to add some annatto when you put in the pearl-ash.
To make the light shades, such ascanaryorlemon, perfectly white, they must be boiled with thirty pounds of soap to a hundred of silk; and if these be notazuredto be dyed, they must have a little of the blue vat, and a little of the weld liquor in water, (the whole mixture being as hot, but no hotter than the hand will bear,) and the silk ready on rods, must be quickly worked through and out. For deeper lemons the same process must be used as for the fuller yellows; only less weld, and twenty pounds of soap will do for a hundred pounds of silk in whitening it.
The blue of the vat is only used for such articles as are to have a green cast, and that extremely light; the aluming also should be in a weaker alum liquor: for light lemons it should be prepared in a separate liquor.
You must have a colander proportioned to the size of the copper in which you boil the annatto. To every pound of annatto put from twelve ounces to one pound of pearl-ashes, which last dissolve in water, and add the solution, by degrees, to the solution of annatto as it boils and dissolves, for which purpose the annatto must be suspended in the colander over the copper by a flat stick about six inches broad, run through a flat handle on each side of the colander, by which means the colander is kept sunk in the water with the annatto in it, till it is all dissolved, except some little foreign matters. The holes in the colander should be moderately small.
Dissolved in this manner the annatto, if kept clean, will keep as long as you please.
These require but twenty pounds of soap for boiling white. To dyeaurorathe silk must be prepared the same as for yellow.
Annattoprepared(as directed in the last article) and settled, is then put into a copper of hot water, in quantity according to the shade required; having mixed it well, the liquor being as hot as the hand will bear, put the silk into it; when one hank is tried, as in the yellow, if it be not full enough, the liquor must be strengthened till the colour is brought to the shade required. When finished the whole must be washed twice and beetled. Theauroraserves as a ground formoidore.
As fustic and logwood are to form part of this dye upon the annatto ground, the silk must be alumed, then washed from the alum, in order that the superflux of the alum may not render the dye uneven. A fresh liquor is then prepared, rather hot, to which must be added a little of the decoction of logwood, and of the decoction of young fustic. The silk is re-turned in this liquor, but if apparently too red, you may put in a very little of solution of sulphate of iron, which will make it sufficiently yellow.
When the silk is dyed with the gum, in the raw state, the annatto must be used nearly cold, or the elasticity of the silk will be destroyed.