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other substances which give a red color, are de. wool. By exposure to the air, this color becomes nominated by Dr. Bancroft adjective colors, from deeper. By boiling the wool for two hours with their requiring the aid of mordants to give them one-fourth of sulphate of iron, then washing it, permanence.
and afterwards immersing it in cold water with 169. Of Dyeing Wool Red.—When woollen one-fourth of madder, and boiling it again for an stuffs are to be dyed, they are first boiled for two hour, the result is a coffee color. But if the or three hours with alum and tartar: they are wool has not been soaked, and if it he dyed with then left to drain, slightly wrung out, put into a one part of sulphate of iron and two of madder, linen bag, and carried into a cool place, where the color is a brown approaching to red. they must remain for soine days. The quantities 172. When sulphate of copper is employed and proportions of the alum and tartar are varied as the mordant, the madder dye yields a clear according to the object of the dyer, and the shade brown, inclining to yellow; and a similar color of color which is wanted. Some recommend may be produced by dyeing the wool simply five ounces of alum, and one ounce of tartar to soaked in hot water, with one part of sulphate each pound of wool. By increasing the propor- of copper, and two of madder. But when this tion of tartar to a certain degree, a deep and per- mordant and dye-stuff are used in equal propormanent cinnamon color is produced. This arisestions, the yellow is somewhat more obscure, from the yellow tinge induced by the acid on inclining to green; and in both these instances, the coloring particles of the madder. Others exposure to the air does not produce a darker propose to diminish the proportion of tartar, and color. Berthollet says that he employed a soluto use only a seventh part. In conducting the tion of tin in various ways, both in the preparaprocess of dyeing with madder, the bath should tion and the application of the madder; and, by not be brought to a boiling heat, because, at that the use of different solutions of tin, he found thai, temperature, the fawn-colored particles would be although the tint was a little brighter than what dissolved, and a different shade obtained from is obtained by the common process, it was always that which is desired. When the water is at such more inclined to yellow or fawn color. a temperature as the hand can bear, Hellot re 173. Of Dyeing Silk Red.—The red color commends the addition of half a pound of grape obtained from madder has not been found of sufmadder for every pound of wool to be dyed. It ficient brilliancy for dyeing silks; M. De la must then be well stirred before the wool is in- Folie, however, has given the following process troduced, which must remain for an hour with- for employing it for this purpose :-Halfa round of out boiling, excepting for a few minutes towards alum is to be dissolved in each quart of hot water, the end of the process, that the combination of to which two ounces of potassa are to be added ; the coloring particles with the stuff may be more after the effervescence is over, and the liquor certain.
has begun to grow clear, the silk must be soaked 170. Madder reds are sometimes rosed, as it is in it for two hours; it is then to be washed and called, with archil and Brasil wood. In this way put into the madder bath. Silk dyed in this way, they become more beautiful and velvety, but he says, becomes more beautiful by the applicathis brightness is not permanent. But madder tion of the soap proof. Another process is dereds, even when at best, are far inferior to those scribed by Mr. Gulichie, of which the following obtained from lac and cochineal, and even to is the substance.that produced by kermes; but, as the expense 174. For every pound of silk he proposes a of the materials is comparatively small, they are bath of four ounces of alum, and one ounce of employed for coarse stuffs.
3olution of tin. When the liquor has become 171. Different authors recommend different clear, it is decanted, and the silk carefully soaked proportions of madder. Poerner proposes to in it for twelve hours, after which it is to be imemploy one-third of the weight of the wool, while mersed in a bath with half a pound of madder Scheffer limits the quantity to one-fourth. Poer- softened by boiling, with an infusion of galls in ner added to the alum and tartar a quantity of white wiue. The bath must be kept moderately solution of tin, equal in weight to the tartar, and, hot for an hour, and then made to boil for two after two hours boiling, allowed the cloth to re- minutes. The silk, being taken from the bath, main in the bath, which had been left to cool for is to be washed in a stream of water, and dried three or four days. He then dyed it in the usual in the sun. The color thus produced is said to way, and obtained a fine red. On another occa be very permanent; and, if the galls are omitted, sion he prepared the cloth by the common boil- its brilliancy is improved. ing, and dyed it in a bath slightly heated, with 175. The color obtained when Brasil-wood is a larger proportion of madder, tartar, and solu- used, is denominated false crimson, to distinguish tion of tin. The cloth remained twenty-four hours it from that produced by cochineal, which is in the bath, and, when it had become cold, he much more durable, and which is styled grain crimput it into another bath, made with madder only, son. This very beautiful color is obtained by the where it remained for twenty-four hours. By following process :—The silk, being well cleansed this process he got a fine red, somewhat brighter from the soap, is to be immersed in an alum hath than the common, but inclining a little to yellow. of the full strength, and to remain for a night. Scheffer says that he obtained an orange red by It is then to be washed, and twice beetled at the boiling wool with a solution of tin, and one-fourth river. · The bath is prepared by filling a long of alum, and then dyeing with one-fourth of boiler two-thirds with water, to which are added, madder. A cherry color, says Bergman, is ob- when it hoils, from half an ounce to two ounces tained by using one part of a solution of tin, and of powdered white galls for every pound of silk. two of madder, without previously boiling the when it has boiled for a few moments, from two
to three ounces of cochineal, also powdered and Permanent Colors. In a solution of muriosifted, for every pound of silk, are put in, and sulphate of tin, diluted with five times its weight afterwards one ounce of tartar to every pound of of water, the silk is to be soaked for two hours; cochineal. When the tartar is dissolved, one and, after being taken out, it is to be wrung and ounce of solution of tin is added for every ounce partially dried. It is then to be dyed in a bath of tartar. In the preparation of this solution of prepared with four parts of cochineal, and three tin, the following proportions are recommended of quercitron bark. In this way a color approachby Macquer. For every pound of nitric acid ing to scarlet is obtained. To give the color more twn ounces of sal ammoniac, six ounces of fine body, the immersion may be repeated both in the grain tin, and twelve ounces of water are em solution of tin and in the dyeing bath ; and the ployed. When these ingredients are mixed toge- brightness of the scarlet is increased by means of iner, the boiler is to be filled up with cold water, the addition of carthamus. A lively rose-color and the proportion of the bath, for every pound is produced by omitting the quercitron bark, of silk, is about eight or ten quarts of water. In and dyeing the silk with cochineal only; and, this the silk is immediately immersed, and turned by adding a large proportion of water to the coon the winch till
appear to be of a uniform chineal, a yellow shade is obtained, which color. The fire is then increased, and the bath changes the cochineal to the compound scarlet is kept boiling for two hours, observing to turn color.' the silk occasionally. The fire is afterwards put 178. Of Dyeing Cotton und Linen Red. out, and the silk put into the bath, where it is Madder is employed for dyeing linen and cotton allowed to remain for a few hours longer. It is red, and even for giving them several other cothen taken out, washed at the river, twice beetled, lors, by means of different mixtures. It is the wrung, and dried.
coloring drug most useful for this kind of dre176. Carthamus, says M. Berthollet, is used ing. It is proper therefore to show, in sufficient for dyeing silk poppy, a bright orange red, cherry, detail, the different methods by which this dye rose color, and ficsh color. The process differs may be rendered more permanent, beautiful
, according to the greater or less tendency to flame and diversified in its effects. Linen takes the color that is wanted. The following is his ac color of madder with more difficulty than count of the preparation of the carthamus bath : cotton : but the processes which succeed best, The yellow matter of the carthamus having been with the one, are also preferable for the other. first extracted, the cakes containing the red co 179. Two species of madder red, on cotton, loring matter are broken down and put into a are distinguished; the one called simply madtrough of fir-wood, where they are several times der red, the other, possessing far more lustre, sprinkled with finely powdered soda in the pro- is called Turkey-red, or Adrianople-red, beportion of six pounds of soda to every hundred cause it was for a long time obtained from the pounds of carthamus. The whole is then put Levant. into a small trough lined with closely woven Vogler tried the effect of a great number of cloth, and having a grated bottom; this small the substances employed as mordants, or in the trough is then placed over the larger one, and dyeing bath, and he found that those which prowater is poured on the mixture till the larger duced the best effect were glue, ox-call, and trough is full. Fresh water is poured over the other animal matters, as sheep's dung. Muriate carthamus and suffered to run into another trough, of soda rendered the color faster, but more dull. and so on successively, adding a little fresh Galling likewise procured a richer color. Other soda till all the red color is extracted. These astringents, sumach and pomegranate rind, for liquors are then mixed, and lemon-juice is instance, produced a similar effect.
A little aladded to give a fine cherry color, which the kali added to the alum improves it. When the liquor imparts to the silk that is dipped in stuff has passed through the different preliminary it. Poppy - color, given in this way, requires operations, it must be dyed with the best madthat the silk be immersed in a second hath, der that can be procured, in the proportion of and that the colors be brightened by turning three-quarters of a pound to each pound of the silk several times through a bath of hot stuff. water impregnated with lemon-juice. The lighter The temperature of the madder hath must be hues of red are given by the weaker solutions of raised in a gradual manner, that may require carthamus, and the lightest shades require the about an hour to boil after the stuff has been imaddition of a little soap. In dyeing silk with mersed in it; and, when it has boiled a few carthamus the silk, after being scoured, should, minutes, the stuff is taken out, slightly rinsed, for poppy or fire color, receive a ground of an- and dyed a second time in a second bath, with notto. The carthamus bath should be prepared the same quantity of madder; after the second at the time of using, and the process of dyeing dyeing, and subsequent rinsing and drying, the should be conducted as speedily as possible.. stuff is commonly steeped in a solution of white
177. Those who have made the nearest åp- soap, made just milk-warm, in the proportion of proach towards producing a scarlet on silk, says two ounces of soap to one pound of stuff. The Berthollet, begin with dyeing the silk crimson. effect of this process is to remove all the uncomIt is then dyed with carthamus, and after that bined coloring matter, and, as is supposed, to dyed yellow in a cold bath. By this process a give a higher degree of brilliancy to what refine color is produced, but it is not permanent, mains. This process is completed by rinsing and as the dye of the carthamus is affected by the drying. action of the air. The following is the process 180. Of all the reds produced hy the use of given by Dr. Bancroft in his Philosophy of madder, the Adrianople or Turke - red is by far
the most beautiful: it possesses a brilliancy Dissolve the pearl-ashes in ten pails, of four which can be communicated to cotton by none of gallons each, of soft water, and the lime in fourthe common processes of dyeing, and has, more teen pails. over, the property of more effectually resisting Let all the liquors stand till they become quite the action of the different re-agents, as alkalis, clear, and then mix ten pails of each. soap, alum, and acids.
For many years the Boil the cotton in the mixture five hours, then dyeing of this color was confined to the east, and wash it in running water and dry it. came to us through our Levant trade only. In Step 2. Take a sufficient quantity, say ten process of time the art found its way from India pails (of four galloris each), of the strong barilla to the western parts of Asia, and to Greece; and water in a tuh, and dissolve or dilute in it two from Greece to France, whence it was brought to, pails full of sheep's dung ; then pour into it two this country by one of the French dyers, M. quart bottles of oil of vitriol, and one pound of Papillon, who settled at Glasgow, where, for a gum arabic, and one pound of sal ammoniac, considerable time, he carried on with great suc- both previously dissolved in a sufficient quantity cess the business of dyeing Turkey-red. of the weak barilla water, and lastly, twenty-five
181. M. Papillon communicated his process pounds of olive oil, which has been previously to the commissioners and trustees for manufac- dissolved or well mixed with two pails of the weak tures in Scotland, to be by them published at barilla water. the expiration of a certain term of years. For The materials of this steep being well mixed, this he received a handsome premium; and tramp or tread down the cotton into it, until it the process was made public in the year 1803. is well soaked; let it steep twenty-four hours,
We need hardly mention the celebrity of the and then wring it hard and dry it. manufactory of Messrs. Monteith and Co. of Steep it again twenty-four hours, and again Glasgow, since it is known to the world at large. wring and dry it. The excellency and beauty of their cotton fa Steep it a third time twenty-four hours, aster brics will not soon be surpassed; the madder- which wring and dry it, and lastly wash it well reds which they dye rival, in brilliancy and in and dry it. solidity, any ever produced at Adrianople; and Step 3. This part of the process is precisely the white figures, distributed over the cloth by the same with the last, except that the sheep's the discharging process, surpass in purity, ele- dung is omitted in the composition of the steep. gance, and precision of outline, the original Ban Step 4. Boil twenty-five pounds of galls, dana outlines.
bruised, in ten pails of river water, until four or 182. The art of dyeing Turkey-red has been five are boiled away; strain the liquor into a tub, described by different writers, who vary a little and pour cold water on the galls in the strainer, from each other in some particulars, but who to wash out of them all their tincture. agree in the leading features of the process. We As soon as the liquor is become milk-warm, prefer inserting here the account of it as given dip your cotton hank by hank, handling it careby Dr. Bancroft, as it afford; us an opportunity fully all the timc, and let it steep twenty-four of following it up by the insertion of some of hours. his truly valuable remarks upon the subject in Then wring it carefully and equally, and dry reference to the process observed at Ronen in it well without washing. France.
Step 5. Dissolve twenty-five pounds of Rois very tedious, and is divided by man alum in fourteen pails of warm water, withthe dyers into nine different steps.
out inaking it boil; skim the liquor well, and add Step 1. Cleaning. For 100 pounds of cotton two pails of strong barilla water, and then let it take an equal weight of Alicant barilla, twenty cool until it be lukewarm. pounds of pearl-ashes, and 100 pounds of quick Dip the cotton, and handle it hank by hank, lime.
The barilla must be mixed with soft and let it steep twenty-four hours, and wring it water in a deep tub, which has a small hole near equally and dry it well without washing. the bottom of it, stopped at first with a peg: Step 6. Is performed in every particular like This hole is covered in the inside with a cloth the last; but after the cotton is dry, you steep it supported by two bricks, that the ashes inay be six hours in the river, and wash and dry it. prevented from passing through it or stopping it Step 7. The cotton is dyed by about ten up while the lie filters through it.
pounds at once, for which take two gallons and Under this tub is another to receire the lie; a half of ox blood, and mix it in the copper with and pure water is repeatedly passed through the twenty-eight pails of milk-warm water, and stir first iub to form lies of different strength, which it well; then add twenty-five pounds of madder, are kept separate at first until their strength is and stir all well together. Then, having beforeexamined. The strongest required for use must hand put the teu pounds of cotton on sticks, dip swim an egg, and is called the lie of six degrees it into the liquor, and move and turn it constantly of the French hydrometer, or peseliqueur. The one hour, during which you gradually increase weaker are afterwards brought to this strength, the heat, until the liquor begin to boil at the end by passing them through fresh barilla. But á of the hour. Then sink the cotton, and boil it certain quantity of the weak, which is of 2° of gently one hour longer; and, lastly, wash it and the above hydrometer, is reserved for dissolving dry it. the oil and gum, and the salt, which are used in Take out so much of the boiling liquor, that subsequent parts of the process. This lie of 2° what remains may produce a milk-warm heat is called the weak barilla liquor, the other is called with the fresh water with which the copper is the strong.
again filled up, and then proceed to make up a
dyeing liquor as above, for the next ten pounds are, by sufficient stirring, to be well mixed with of cotton.
the lie and with each other; and, in the mixture, Step 8. Mix equal parts of the gray steep which contains but half the quantity of oil preliquor, and of the white steep liquor, taking five scribed by M. Papillon, the cotton is to be or six pails of each. Tread down the cotton steeped, &c., as directed by the latter. It is into this mixture, and let it steep six hours, then highly important that, after this and each of the wring it moderately and ecually, and dry it succeeding operations, the cotton should be without washing.
thoroughly and completely dried by a stove heat. Step 9. Ten pounds of white soap must be Step 3. At Rouen this steep is prepared by dissolved most carefully and most completely mixing thirty-eight gallons of lie of soda with sixteen or eighteen pails of warm water; if any ten pounds of olive oil, stirring until the mixture little bits of the soap remain undissolved they becomes uniformly milky; which it will do will make spots in the cotton. Add four pails without any separation of the oil, if the quality of strong barilla water, and stir it well. Sink of the oil be suited to this use; this they add to your cotton in this liquor, keeping it down with what may have been left of the former steep, cross sticks, and cover it up and boil it gently and, after mixing them properly, they impreztwo hours, then wash and dry it, and it is nate the cotton by the usual treatment, drying it, finished.
after an interval of twelve hours, first in the open Such is the process of M. Papillon, on which air, and afterwards by a stove heat. This steepDr. Bancroft makes the following observations. ing and subsequent drying must be repeated
Step 1. At Rouen two courses of operations once, twice, or three times, according to circumare practised to produce the Turkey-red. One stances. is called the gray course, and the other the Between this white steep and the following yellow course. In the former, the cotton, after gall steep, it is the practice at Rouen to employ being alumed, receives no more oil, but goes to three salt steeps and one cleansing operation. In the dyeing vessel, retaining the gray color, which the first, twenty-four gallons of the lie of soda, naturally results from its being impregnated with marking two degrees and a half, are mixed in a alum and galls in combination. But, in the tub with the remnant of the white steep; and yellow course, the cotton, after being alumed, is the cotton is impregnated and dried, as in the again immersed in the oleaginous mixtures or former operations. In the next the remnant of steeps, by which
acquires a yellow color. The the last steep is mixed with twenty gallons of the gray course may consist either of fifteen steeps lie of soda, marking three degrees; and the or of nineteen, and the yellow of twenty. The cotton is steeped and dried as before. In the third, first of these courses has most similitude to that the remnant of the preceding steep is mixed with of M. Papillon. At Rouen, the cleansing opera- twenty-four gallons of the lie of soda, marking tion is performed with a very weak lie of soda, three degrees and a half, and with this the cotton of only one degree of the areometer, employing is impregnated and dried as before. The resi150 gallons to 100 pounds of cotton, which is to duum of this steep is preserved to be used in the be boiled therein six hours, then drained, well brightening operation. rinsed in running water, and afterwards dried. In the cleansing operation, the cotton is This operation is intended to free the cotton steeped one hour in lukewarm water, then from all impure or extraneous matter; but not wrung by hand, and afterwards washed in a to produce effects like those of bleaching by ex- stream of water to remove any superfluous oil posure upon the grass, which, until lately, it which might obstruct the equal application and was believed, would lessen the durability of the uniform effect of the following gall-steep, and colors to be subsequently dyed.
thereby render the color unequal. After being Step 2. The steep here described contains so washed, the cotton is dried first in the open three ingredients not employed by any other air, and afterwards by a stove-heat. person; and one of these, the sulphuric acid, Step 4. This constitutes the eighth operation seems to indicate a want of chemical knowledge in the gray course at Rouen, where, as well as in M. Papillon, because, by neutralising the soda, in M. Papillon's process, galls, in sorts, seem it must obstruct the effect which the latter is in- now to be employed. At Rouen, the cotton, as tended to produce (that of rendering the oil soon as it has sufficiently imbibed the soluble miscible with water), or at least render a greater matter of the galls, and been very moderately proportion of it necessary in order to obtain that wrung, is spread as expeditiously as possible in effect. In regard to the other two ingredients, the open air, if the weather be dry, or, if not, viz. the gum and sal ammoniac, the quantity of under cover; but the drying is always finished the former is by much too small to produce any by a stove heat. considerable effect, and it is not easy to form any Step 5. At Rouen, thirty or thirty-five pounds conjecture what purpose the latter is to answer. of the purest alum are commonly employed for At Rouen, this steep is prepared by steeping this steep, with only seven pails of hot-water, twenty-five or thirty pounds of sheep's dung se- adding, when the alum has been dissolved, two veral days in a lie of soda, marking four degrees, gallons only of the lie of soda, marking four dewhich is to be diluted until it amounts to forty grees. But when these proportions are em, gallons; and the dung being squeezed and ployed, the cotton is not subjected to a second broken by the hands, is afterwards made to pass steep with alum. Sometimes, however
, at Rouen, through a copper pan, provided with numerous two steeps with the aluminous mordants are emsmall holes, into a tub containing twelve pounds ployed; and in that case twenty pounds of alum and a half of fat oil, and in this the oil and dung are dissolved for the first, and fifteen for the sea
cond, leaving an interval of two days between mentioned, lest it should decompose the soap, them, during which the cotton should retain its aud cause the oil to separate and rise to the surmoisture after being slightly wrung from the face of the liquor. first steep. It should, however, be well dried 183. We cannot leave this truly important branch before it goes into the second.
of dyeing without noticing the ingenious remarks Step 6. At Rouen, the cotton is dyed in par- of Mr. Thomson of Glasgow, published in ihe cels of twenty-five pounds each, and the dyeing eighth volume of the Annals of Philosophy, on vessel is of a quadrangular form, containing about the theory of the Turkey-red process. 100 gallons of liquor. One quart of ox-blood is He observes that silk and worsted have a employed for each pound of cotton, with two natural varnish which cotton does not possess. pounds of Provence madder, or one pound of this To supply this defect, the repeated immersions, with one of Smyrna madder. Some persons, followed by exposure to the atmosphere, and to however, think it best to effect the dyeing by the heated air of a stove, may give the oil the two separate operations, employing half the above proper consistency, by the absorption of oxygen, proportion of madder for one dyeing, and half for forming a varnish, with which the coloring for the other; but always taking care not to dry matter unites, and through which it may be said the cotton between the dyeings. There are some to shine, which causes that superior brilliancy at Rouen who give cotton another alum steep which the goods attain when they are cleared, or, between these dyeing operations, employing for as it may be called, polished. I therefore prethat
purpose half as much alum as was used for sume, that the fixedness and brilliancy of the the first steep, and afterwards washing, &c. color will depend on the quantity of oil imbibed,
Step 8. For this steep they employ at Rouen as every repetition of drying presents new fibres the residuum of the third salt-steep before men to be varnished with an additional quantity; for tioned; but the application of it is considered a I have always found, that the permanency was part of the following step.
in proportion to the number of manipulations in Step 9. This constitutes the fourteenth opera- the saponaceous liquor, and a proportionable freetion in the first set of gray courses at Rouen; dom could also be used in reducing or clearing. where, after having macerated the cotton with The white immersions, omitting the sheep's dung, the sikiou, they boil it for the space of five are just applying successive coats of varnish. or six hours with six or eight pounds of white Clearing is never attempted from the madder soap, previously dissolved in 145 gallons of copper, without immersing the goods again in water, in a vessel covered at the top, so as to soda and oil, and drying them in a stove, which leave only a very small opening for the neces- I consider to be also supplying them with an sary escape of the steam, which might otherwise additional coat. occasion an explosion. The effect of this boiling
The alkaline lie occasions a greater separation with soap, is to dissolve and separate from the in the particles of the oil, by which it combines cotton all the yellowish-brown matter of the more closely with the fabric of the cloth. The madder color which may have been applied to it sheep's dung in the first immersions may serve in the dyeing operation, and thus to change the as a covering, to keep the goods moist for a concolor from the dull brownish-red which it would siderable time, that they may more fully imbibe otherwise retain, to a bright lively color, nearly the liquor, by preventing the evaporation from equal to that of the finest cochineal scarlet. It being too quick in the great heat to which they is only by the singular degree of fixity which the are exposed. pure red part of the madder color acquires, in After the frequent immersions the cloth feels consequence of the operations just described, like leather, no doubt from a superfluity of liquor. that this beautiful red can be obtained. Such, It is then steeped in a lie of carbonate of soda, indeed, is the stability of the Turkey-red when and afterwards well washed and dried, as a prewell dyed, that it is said to sustain boiling with paration for the galling and aluming. The soap for thirty-six hours without injury. astringent principle has been long known for
In addition to the steps prescribed by M. darkening and fixing common red colors on Papillon, they employ another at Rouen, which cotton, by uniting with the earth of alum, and is intended to make the red incline more to the strengthening the basis. To the use of blood in rose color, and at the same time increase its vi- the madder copper I attribute nothing; as in the vacity For this operation, with the former rancid and putrid state in which I have seen it quantity of 100 pounds of cotton they dissolve, used, were it not for the prejudice of the operain 145 gallons of water, sixteen or eighteen tor, it might be safely dispensed with. pounds of white soap, and as soon as the liquor In proof of the above idea, that it is only the begins to boil, they add to it from one pound oil uniting with the earth of alum that is of use, and a half to two pounds of the crystallised mu- 1 may refer to the mode of dyeing that color in riate of tin, previously dissolved in two quarts of the east, quoted by Dr. Bancroft, viz. soaking water, and mixed with eight ounces of single their cotton in oil (no matter of what descripaqua-fortis; and having equally dispersed this tion), during the night, and exposing it to the mixture through the boiling solution of soap, hy sun and air during the day, for seven successive stirring, &c., the cotton is put in and boiled with days, rinsing it only in running water, and then the same precautions as in the brightening opera- immersing it in a decoction of galls and the leaves tion, till the desired effect has been obtained, of sumach previous to aluming. which is to be discovered by frequent examina I would therefore request the practical dyer, tions. Care must be taken not to employ more who wishes to arrive at a knowledge of this unnitric acid or aqua fortis than the quantity here accountable process, to give up the idea of ani