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carbonate of soda, to which is added 50 grammes of an alcoholic solution of azaléine. After an hour's ebullition, the red colour is transformed into the Bleu de Mulhouse. Azuline. This beautiful blue colour, which resists the action of the strongest acids, and which was introduced into this country at the latter end of 1860, by Messrs Guinon, Marnas, and Bonnet, of Lyons, is prepared by them from phenic acid, and, when pure, presents itself under the form of copper-bronze coloured crystals, soluble in alcohol, to which they communicate a magnificent blue colour, slightly tinged with red. The following is the process for dyeing silk and wool:-To an acidulated lukewarm bath of water an alcoholic solution of azuline is added, and the silk or wool worked in it until it is of the required shade. It is then transferred to another bath of boiling water, strongly acidulated with sulphuric acid, when the purple colour is dissolved, leaving a most brilliant and permanent blue upon the material. The dyed silk or wool is washed repeatedly, passed through a bath containing a little tartaric acid, and dried.

1859, by Mr. Rudolph Heilman, in which the employ-grammes of white gum lac in powder, and 18 grammes of ment of arsenic acid is mentioned, and one also for the employment of the same agent on the 18th of January, 1860, by Dr. H. Medlock. As it is probable that this agent is the best suited for producing magenta, commercially, I will give a sketch of the process. Dr. Medlock heats two parts of aniline with one of arsenic acid to about 2502, and when the red colour is produced it is mixed with boiling water and allowed to cool. The red colour is thrown down by saline matter, washed, and dissolved in methylated alcohol, or the mass is digested in hydrochloric acid diluted with water, and the clear fluid solution is saturated with an excess of soda which precipitates the colour, while the arsenious acid is held in solu tion by the alkali. Magenta is a rather powerful organic base which is sparingly soluble in water, but its solubility is increased by the presence of an acid. It leaves a brittle mass, having a beautiful golden green metallic reflection when its alcholic solution is left to spontaneous evaporation, and this is not peculiar to magenta, as the whole of the coal tar colours, when in a high state of purity, present the same appearance. Purple aniline differs from the red, not only in its composition, which is as follows

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but also because the fuchsine dissolves in ammonia and in sulphuric acid with a yellow colour, and is discoloured by sulphurous acid, whilst the purple is unaffected by those reagents. Silk or wool is dyed with fuchsine by simply adding some of the colour to a slightly acidulated bath. The dyeing colour of this material is so great that 10 grains will dye 2 square yards of silk.

Chinoline Blue.-Mr. C. Greville Williams introduced in the spring of last year a fine blue colour, which he obtained by boiling together a substance derived from quinine or cinchonine, called chinoline, with iodide of amyl. The resulting product is boiled with water and then with potash for a quarter of an hour, filtered to separate the resinous matter, when a gorgeous blue is obtained, with scarcely any shade of red. This colour is so fugitive that its use

has ceased.

Green Colours from Aniline.-Although it has been known to chemists that aniline would yield a green colour under certain oxidising agents, up to the present time all Of late years many attempts have been made to fix efforts to dye silk or wool commercially with it have failed, another colour obtained from coal tar, called rosalic acid but to avoid having to refer to this green colour again I (C12 H O), but up to the present time I believe all at- may mention that Messrs. Samuel Cliff, Charles Lowe, and tempts have failed, with the exception of rosalate of mag-myself, patented, on the 11th of June, 1860, a most easy and nesia, which was employed for some time in calico printing. Blue colouring matters from Coal Tar.-I have already drawn your attention to the blue colouring matter patented by Mr. Girard, and carried out practically by Messrs. Renard and Franc, of Lyons. Mr. Lauth also has observed that if an alcoholic solution of red aniline, and especially azaléine, is heated with a reducing agent, such as protochloride of tin, or still better with aldehyde or hydruret of benzoïle, a blue colour is produced even at ordinary temperatures. This blue colour is soluble in water, alcohol, and acetic acid, but does not resist the action of mineral acids, alkalies, or light.

Mr. Willm has recently published an interesting paper on this aniline blue, which not only shows how aldehyde acts, but exhibits the composition of the blue itself.

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2 (C36 H20 N4 О1) † 5 С ̧ н ̧ 0 + 8 HO Blue or Oxyphenylanilide.


4 4 4
Acetate of Ammonia.

= 3 (C34 H12 NO3) + 5 C, H ̧ (N H1) O Therefore the triamine azaléine has been transformed into a monamine blue, by a new chemical reaction, for aldehyde not only acts as a reducing agent, but converts a part of the nitrogen into ammonia.

Bleu de Paris. Recently, Messrs. Persoz, de Luynes and Salvétat called public attention to a new blue which they had produced, and to which they gave the name of Bleu de Paris; this they prepared by heating for thirty hours, in a sealed tube, at a temperature of 356°, one part of anhydrous bichloride of mercury with two parts of aniline. The blue thus produced can resist the action of weak acids and alkalies, but assumes a red hue when acted on by these agents in a concentrated state. Sulphurous acid has no action upon it, and it dyes animal fibres with facility.

Bleu de Mulhouse.-MM. Gros-Renaud and Schaeffer have lately published an interesting process for obtaining from the red aniline, called azaléine, a purple and a blue. It consists in dissolving in a litre of boiling water, 50

practical method of producing it under the name of Emeraldine, on cotton fabrics, specimens of which I have the honour to show you. The process consists in printing an acid chloride of aniline on a cotton fabric prepared with chlorate of potash, and in a few hours a beautiful bright green gradually appears, which only requires to be washed. If the green fabric is passed through a solution of bichromate of potash, this colour is transformed into a dark indigo blue, called by us azurine.

Naphthaline Colours.-The beautiful solid hydro-carbon naphthaline, which has yielded such a long category of substances to the chemists, has up to the present time yielded nothing of practical importance to the dyer, with the exception of a case which I shall mention presently. From it the following coloured derivatives have been obtained, namely, chloroxynaphthalic acid, perchloroxynaphthalic acid, carminaphtha, ninaphthalamine nitrosonaphthalin, naphthamein, and a body of a purple colour. It is to Mr. Perkin that we owe the knowledge of several of these substances and their colour-giving properties. In my laboratory a fine purple colour has been obtained from naphthalin, which dyes with facility silk and wool, and the process is so far perfected as to enable me to show you some silk dyed and a piece of calico printed with it.

A few months ago the scientific world were startled by the announcement, from a French chemist named Z. Roussin, that he believed he had discovered the means of making from naphthaline the important colour-giving principle which I have already mentioned to you when speaking of madder called alizarine, and what strengthened his belief was, that he thought he had succeeded in removing two equivalents of oxygen from binitronaphthaline, and transforming the nitrogen thereof into ammonia, leaving, as a residue, alizarine, as seen by his formula:

ject of coal tar colours, should consult the number for October, *Those who may wish for further information on the sub1861, of the quarterly journal of the Chemical Society, which contains a valuable paper by Mr. W. A. Perkin.


Minus oxygen
Plus hydrogen

Plus ammonia

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unattainable by any other known means. For instance, owing to various improvements, rollers of 43 inches in circumference and 44 inches long have been introduced, enabling the calico printer to produce cheaply large furniture patterns.

En passant, I wish to call your attention to an application which has been made of a process greatly admired by many Mercer, the eminent calico printer, by which the beauty of of you at the Exhibition of 1851, invented by Mr. John dyed and printed goods was increased by passing the cotton fabrics through a strong solution of caustic lye, and afterwards through a weak solution of sulphuric acid, and then thoroughly washing. If this process has not been generally adopted, it is no doubt owing to the contraction which the cotton fibres experience under the above chemical influences, but the increased strength which the fibre thus acquires has been turned to good account, by enabling the printer to use it as a substitute for what is technically termed the "blanket" that is an endless cloth which passes over the engraved rollers with the goods to be printed. This material is found by its strength to resist better than most others the heavy strain which the blankets have to undergo during printing.

Plus water, The simple process which he devised to obtain a crystalline substance which gave a red colour with an alumina mordaunt, consists in dissolving slowly binitronaphthaline in concentrated sulphuric acid, and raising the temperature gradually to 3920, when he adds granulated zinc in successive small portions. After a short time sulphurous acid is given off, and the conversion of binitronaphthaline into a red colouring matter is effected. All that is now required is to dilute the liquor with eight or ten times its volume of water, and carrying it to the boil, filter, and allow the whole to cool, when Mr. Roussin's so-called alizarine deposits under the form of fine red or orange coloured crystals. Although this product possesses some properties similar to those of alizarine, it differs from it in many of its chemical reactions, and also because it does not furnish the purple and chocolate Singeing.-I shall here also allude to two improvements colours given by alizarine with iron, and iron and alumina effected by Mr. John Thom, of Manchester. The first, mordaunts. Still these results, arrived at by Mr. Roussin, applicable to all kinds of cotton or woollen fabrics, destined are so remarkable, that it is to be hoped that he will per- for printing or dyeing, consists in an improvement in the severe in his endeavours to solve this interesting problem. singeing or removing the nap from fabrics. The usual I cannot conclude this part of my paper without draw-mode is to pass the fabrics either through a gas flame, or ing the attention of those interested in the subject of over a semi-circular heated iron plate. In the latter case, colours, to a series of valuable papers, which have recently however, a large amount of fuel was wasted in maintaining been published in the memoirs of the Institute of France, the heat of the plate, owing to the free radiation of heat by my eminent and learned master, M. Chevreul, on the into the atmosphere, and to its absorption in the currents comparative affinity of various colouring matters for differ- of cold air in contact with the plate. Mr. Thom's inent fibres, on the influence of various mordaunts, on divers vention remedies these defects, by enclosing the plate colouring matters, and, lastly, on the influence of the solar under a brick arch, so that no air can enter the light on such dyed fabrics. chamber except that which passes with the piece, and that limited quantity is, by a proper arrangement of flues, conducted into the furnace which heats the plate. The drawing which I have the pleasure to show you will fully explain this arrangement.


The art of calico printing depends upon so many branches, of mechanical as well as of chemical science, that it is impossible for me to give detailed information of all the improvements which every department of this manufacture has undergone, during the period embraced by this lecture, but I shall draw your attention to a few of the prominent points that have come under my notice.

Sulphuring. The second improvement of Mr. Thom was devised some years ago, but it is only recently that it has come into general use amongst printers. It is especially applicable to mixed fabrics, such as mousselines-delaine, which require, after they have been singed and before they are printed, to be bleached. This was formerly effected by hanging, for several hours, the moist pieces in chambers filled with sulphurous fumes, and is now performed by Mr. Thom's process in a few minutes, by passing them over a number of rollers confined in a chamber filled with the same vapours.

Thickening Substances. It will be readily understood that it is necessary that the mordants or colours to be printed, should be of sufficient consistency to remain on those parts of the fabrics when they are left by the rollers, so as to produce sharply-defined patterns, and as a great variety of chemical products are employed a great variety of thickeners becomes also necessary. Thus flour, starch, farina, various natural gums, albumen, lactarine, gluten, and several preparations of flour and starch called calcined farina, and patent gums are used. For details of the improvements effected in patent gums I must refer you to the lecture which I had the honour to deliver, on the 21st December, 1852, before this Society.

Engraving of Rollers.-This branch of calico printing has made great progress. Not only have the engravings acquired sharper outlines and finer details, but the methods of engraving have greatly multiplied. I may cite as instances the application of the principle of the pentagraph, by Messrs. Smith, so as to trace patterns on the surface of rollers. Also, calico printers have extensively availed themselves of Mr. Locket's improvements for producing the groundwork of prints, or as they are termed “covers," by applying eccentric engraving," or etching, which produces with facility most complicated patterns on a varnished roller, by means of a diamond point guided by machinery. Another improvement, highly interesting in a scientific point of view, is the application of galvanism to the diamond tracer. By combining the galvanic action with an eccentric motion, most beautiful and delicate engravings may be produced. This is done by tracing the pattern with varnish on a zinc cylinder, which is so placed in the engraving machine that as a needle passes over its surface and comes into contact with the zinc, the galvanic current is established, and by simple machinery causes the Madder Styles.—Although there has been no marked diamond to trace the corresponding pattern on the copper change in this important branch of calico printing, still roller. The communication is so rapid and precise that there are one or two departments in which considerable a great saving of time is effected. But if mechanical art improvements have been effected, to which I desire to has greatly assisted the engraver, chemistry has rendered draw your attention, and to enable you better to underhim equally important services, by enabling him to abandon stand the nature of these improvements, I shall describe costly and cumbrous modes of impressing by force the de-them in the order in which they come into play in the signs on the cylinder, substituting for them a great number production of this class of goods. The first is the imof etching processes. By some of these processes, as by provements in patterns, arising out of the before-mentioned every other addition to the resources of the engraver, an advances in the art of engraving. Secondly, a saving in entirely new and beautiful class of engraving is produced, the quantity of mordant used; for the fact which I have


The mordant, as already explained, does not become fully "aged" by this process alone, although as much so as if it had hung a whole day in cold air. It has received, however, the requisite quantity of moisture (about 7 per cent. of the weight of the printed piece), and is thereby enabled, if an iron mordant, to take oxygen from the air, and to become changed (with time) into the sesquiacetate and sesquihydrate of iron. In order to be sufficiently aged, it must be left one or two, or even three days in an atmosphere still warm and moist.

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already stated with reference to commercial alizarine, viz., | which is made to issue gently from three rows of trumpetthat weaker mordants are required, has been proved by mouth openings. The temperature is raised from 80 to Mr. Pincoff to hold good with all the other preparations 100 degrees, or more of Fahrenheit-a wet-bulb therof madder, the strength of the mordant required to ob-mometer indicating at the same time 76 to 96 degrees, tain the same intensity of shade being less, in proportion or always four degrees less than the dry-bulb thermomeas the colouring matter is purer. It is also advisable ter. In this arrangement 50 pieces of 25 yards are that I should here state that the mordants generally exposed at one time, and as each piece is a quarter of an used for madder styles, are the pyrolignites, or acetates of hour under the influence of the steam, 200 pieces pass iron and alumina, which under the influence of "ageing," through in an hour. Although workpeople need scarcely to be described presently, are so decomposed or modi-ever enter the warmest part of this chamber, a ventilator fied as to leave on the cloth, either an insoluble oxide or in the roof is opened when there is any considerable subsalt, which becomes the intermediate agent for fixing evolution of acetic acid. on the fabric the colouring matter called alizarine, iron giving from a dark purple to a light lilac, alumina from a dark red to a pink, and a mixture of these two mordants a variety of chocolate tints. Thirdly, the most important improvement which has taken place in this branch of printing, viz., a great saving of time and labour in the fixing of mordants by ageing, was first practically carried out by Mr. Walter Crum, the eminent scientific calico printer. Dr. Schunck says that, "On the proper ageing of printed goods depends, in a great measure, the success of many styles; should a room be too hot or too dry, imperfect fixation of the colour ensues, and meagre and uneven tints are obtained in the subsequent operations. To give a further idea of the importance of this step in calico-printing, I may state that ageing-rooms' as they are called, are in several print works of enormous dimensions, and are generally separate buildings. Those of Messrs. Edmund Potter and Co., and Messrs. Thos. Hoyle and Co., may be particularised as forming quite a feature in their works." The process of "ageing" in calico printing is that by which a mordant, after being applied to a cotton fabric, is placed in circumstances favourable to its being completely incorporated with, and fixed in the fibre. It has generally been found desirable that calico printed with a mordant, should, before dyeing, be exposed to the atmosphere for some time in the ageing-room in single folds, which, generally speaking, requires several days, the object being, as before stated, to liberate the acetic acid from the acetates of iron or sulpho-acetate of alumina, and to oxydise the oxide of iron. It was for many years believed that oxygen was the only necessary agent, and although some printers had observed that moisture facili-jets in the same position are made to project steam ditated the process, this fact was not generally known until Mr. John Thom, of Manchester, claimed the introduction of moisture as an important agent in the phenomena of ageing, in a patent which he took out in 1849. The first printer, however, who, as far as I am aware, practically applied this principle, was Mr. Walter Crum, F.R.S. But I cannot better show you the great saving effected by the judicious employment of steam in this process, than by giving you, in Mr. Crum's own words, the particulars of the plan adopted at Thornliebank printworks:

“A building is employed 48 feet long inside and 40 feet high, with a mid wall from bottom to top running lengthwise, so as to form two apartments each 11 feet wide. The manner in which they are fitted up will be understood by reference to the drawing.

"In one of these apartments the goods first receive the moisture they require. Besides the ground floor, it has two open sparred floors 26 feet apart, upon each of which is fixed a row of tin rollers, all long enough to contain two pieces of cloth at their breadth. The rollers, being threaded, are set in motion by a small steam-engine, and the goods to be aged, which are at first placed in the ground floor, are drawn into the chamber above, where they are made to pass over and under each roller, issuing at last at the opposite end (on the right-hand side of the drawing), where they are folded into bundles on one (at a time) of the three stages which are placed there. These stages are partially separated from the rest of the chamber by woollen cloths.

"While the goods are traversing these rollers, they are exposed to heat and moisture, furnished to them by steam,

It had fortunately been ascertained long before, at Thornliebank, that exposure in single folds after moistening was not necessary. Mr. Graham's experiments on the diffusion of gases through small apertures had served to suggest that for the absorption of the small quantity of oxygen required, the goods might as well be wrapped up and laid in heaps. Accordingly, in the operation in question, the moistened goods are carried in bundles into the building on the opposite side of the mid-wall already mentioned, and deposited there upon the sparred floors which are placed there at heights corresponding with the stages in the first apartment on which the goods are folded down. Upon these floors seven or eight thousand pieces may be laid at a time, and as each piece is 25 yards long, 100 miles is therefore the quantity that can be stored at once. It is necessary, of course, that an elevated temperature, and a corresponding degree of moisture, be preserved in the storing apartments day and night, and 80° Fahr. is sufficient, with the wet bulb at 76°. To effect that object a large iron pipe is placed along the ground-floor underneath, and moderately heated by steam, while a row of small rectly into the air of the apartment. The whole building is defended from external cold, and consequently from condensation of steam, by a warmed entrance room, and by double windows and double roof. Small steam pipes are also placed at other points where they seem to be required; and the apartment with rollers is specially heated, when not in use, by a couple of steam pipes, which are placed under the ceiling of the ground floor.

"The process of ageing, as thus detailed, was in operation at Thornliebank, in the autumn of 1856. About a year afterwards it began to be adopted by other printers, and now it is already in use at, at least, sixteen different printing establishments in Scotland and in Lancashire."

Fourthly, Dung Substitutes.-During the last few years the various dung substitutes, such as the double phosphate of soda and lime, the arsenites and arseniates of soda, and the silicates of soda have completely taken the place of cow dung in the process of dunging, that is to say, a process which consists in passing the mordanted and aged cloth into weak and hot solutions of the above-named substances, with the view of fixing thoroughly the mordant in the cloth, and removing any excess that may have been used, without allowing it to fix itself on the white, or unmordanted parts. By the introduction of these dung substitutes, and improved dunging vats, a great saving of time, labour, and expense has been effected. Thousands of pieces are now done in the same vat, where formerly as many hundreds only could be so heated.

Fifthly, Washing Machines.-As madder goods have to be thoroughly washed, not only after this operation, but also after dyeing, several improved machines have been

introduced in the trade. I shall only here mention those of Messrs. Mather and Platt, Mr. Furnival, Mr. D. Crawford, the last of which is much used for steam work and loose colours, and especially that of Mr. Thomas Whittaker, which I have heard highly praised by madder and garancine printers, and a model of which I have the pleasure to lay before you, through the kindness of Messrs. Christopher Whittaker and Co. To give you an idea of the vast capabilities of some of those machines, I will cite the following fact mentioned by Messrs. Whittaker:“Our machine will wash 6,000 yards for all kinds of dyeing purposes, and 12,000 yards for all bleaching purposes, per hour (which only requires the attention of a person of 12 or 14 years of age)."

terns are required, the pieces are printed before dyeing with what is called a "reserve," that is, a composition which prevents the colour from fixing itself on the fibre; the chief ingredient for that purpose is sulphate of copper, which acts by prematurely oxydising the indigo, and thus preventing its fixation. In both these cases the pieces are passed through a weak sulphuric acid bath to perfectly fix the indigo, and formerly the copper thereby liberated from the fabrics was completely lost. Mr. Joseph Leese has recently devised a method of saving this valuable metal. To effect this, the diluted solution of sulphate of copper is made to filter through vessels containing wrought-iron turnings, the acid thus dissolving the iron, which may be used as sulphate of protoxide of iron for future operations, whilst the copper deposited on the excess of iron employed may be used, if thought fit, to manufacture again sulphate of copper. To give an idea of the importance of small savings, I may state that this ingenious, but apparently trifling improvement, saved at least £3,000 a-year to one firm.

Secondly. A few years ago I was able also to effect an economy in this branch of calico printing, which consisted in extracting from the cold indigo vats which were considered by the printer to be exhausted, a considerable percentage of the indigo originally employed. Having observed that a green insoluble flocculent matter, which remained in the vats, and which was considered by chemists and printers to be simply oxide of iron, was in reality a compound of indigo and iron, I devised the following simple means of extracting the indigo therefrom: several exhausted indigo vats into a general receptacle, and there mixed, first with a small quantity of hydrochloric acid, so as to remove the excess of lime, allowing the green pulp to settle, and running off the liquor. The so purified green pulp was then treated with strong hydrochloric acid, when chloride of iron was produced, and the indigo liberated, which required only to be washed to become again fit for use.

Sixthly. After the madder goods have undergone the above improved processes they are ready for the dyebeck, where the mordants assume the colours for which they are adapted. Here, also, a slight improvement has been effected, the advantage of which is a saving of time; as it now requires for saturating the mordants with alizarine only 1 hours for garancine and 2 hours for madder. After leaving the dyebecks the pieces are thoroughly washed in the improved washing machines, but as the white parts (or those not mordanted) are still soiled and the colours dim, it is necessary to pass the pieces for half an hour into a rather strong soap solution heated to 180°, when the loose dye is not only removed from the white parts, but also from the parts on which colour has been fixed. To finally brighten the colours and completely clean the white portions, the pieces are passed into a weak solution of what is called " chimic," or an-The green pulp alluded to was conveyed from the alkaline hypo-chlorite of soda, with a little sulphate of zinc, until the desired effect is obtained, but latterly this process has been improved by passing the goods rapidly into chimic and then through a steam-chest. As the pieces have not yet, however, a commercial appearance, they further undergo what is called finishing, that is, the pieces are passed through a solution of sour flour (flour which has been fermented for several weeks), starch, farina, &c., and then between rollers, dried, and lastly through calenders, the object of which is to fill up the interstices of the fabrics and to give them a glossy appearance. Much improvement has also taken place in this department of printing by the introduction of new machinery, especially in the methods of adapting the finish to the various markets of the world. I wish to take the opportunity of impressing upon printers the importance of dispensing. as much as possible, with the use of sour flour, and confining themselves to that of starch or farina, with the addition of about 1 ounce of sulphate of zinc per piece, for the purpose of diminishing the risk of mildew and other stains, to which a low class of printed goods are liable, during their transit in tropical climates, and especially those dyed with common garancine, bark, sumach, and peachwood.

In concluding my remarks upon madder, I wish to draw your attention to these beautiful examples of madder styles, for which I am indebted to Messrs. Symonds, Cunliffe, and Co., and of garancine styles to Messrs. Wood and Wright.

Indigo.-Most of the styles obtained with this valuable dye-stuff are due to the mixture of printing and dyeing, and only a few improvements have been effected herein, to my knowledge, during the last ten years.

Thirdly. Although the printing of indigo offers great difficulty, still several printers have recourse to it from time to time, with greater or less success. The usual method of printing indigo consisted in mixing finelypowdered indigo with orpiment, or protochloride of tin, with a caustic alkali, and this process was further facilitated by printing the pieces in an atmosphere of coal gas, as devised by Mr. Bennett Woodcroft, the present learned officer of the Great Seal Patent Office, and carried out by Messrs. T. Hoyle and Sons, of Manchester. But of late years Mr. Joseph Leese, of Messrs. Kershaw, Leese, and Co., has succeeded in applying the following method, first devised by Mr. Fritzsche. The indigo is finely ground, and reduced to an impalpable powder, and then mixed with glucose, lime, and caustic soda, in such proportions as are needed to produce the shade of colour required. These materials are all mixed cold, and after the cloth is printed with the mixture it is passed through a steam chest, in which it is exposed for the space of from 30 to 60 seconds. In this short period the indigo is completely reduced and rendered soluble, when it enters into the fibre, and on emerging from the steam chest it becomes oxydised and fixed by exposure to the atmosphere, or the pieces may be immersed in a solution of an oxydising agent, such as dilute sulphate of copper, after which they only require to be washed, dried, and finished.

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First, the usual method of dyeing cotton, plain or self blue, is to fill with water large stone vats, and dissolving in them I am not aware of any marked improvement in the two parts of sulphate of protoxide of iron, adding one part style of printing called spirit colours," but in that of of finely ground indigo, and then three parts of hydrate of "steam colours" considerable advance has been made lime. After having well stirred the whole for several since 1851, rather, however, in a mechanical and artistic, hours, pieces of calico which have been hooked on a frame than in a chemical point of view. Thus, it was owing to and dipped in lime water, are then plunged for 15 mi- certain mechanical improvements that Mr. Robert Kay, nutes into the vat, when the blue indigo which has been calico printer of Manchester, and his workmen, had the converted into white indigo by the protoxide of iron, and honour of obtaining the gold medal at the Paris Exhirendered soluble by the excess of lime, fixes itself on the bition of 1855. The beautiful furniture patterns which he fibre, and, on the exposure of the latter to the atmosphere, exhibited there were the result, not only of artistic skill, re-absorbs oxygen and becomes blue. When white pat-and of improved machinery, by which twenty colours

can be printed at once, but also of an invention patented by Mr. J. Burch, of Macclesfield, of which Mr. Kay availed himself with great tact. Of course you must be aware that, in order to produce light shades of colour, the darker shades are diluted with gum-water, or reducing liquid; this was the work of the colour mixer, and, therefore, to produce four colours and four shades of each colour, sixteen rollers would be required. Now the invention of Mr. Burch consists in reducing the colour upon the cloth during the process of printing. The pattern of the paler shades of each colour in a chintz design being engraved on one roller, an impression in gum-water or reducing liquid is given off upon the cloth first, the impression of the other rollers then following in the usual order; where the different colours fall upon the gum-water a lighter shade is produced, owing to the dilution of the colour on those parts, which effect may be still further heightened, by more lightly engraving the corresponding parts of the colouring roller, so that a less quantity of colour shall be given off. The application of this process to furniture styles, first by Mr. Kay, and of late by Messrs. Littlewood and Wilson, and other large calico printers of Manchester, together with the substitution of the large rollers above mentioned, for block printing, has produced quite a revolution in furniture styles.

powder, which requires only to be well washed and drained to be ready for use. The peculiarity of this green, as well as of one prepared by Mr. Arnaudon, of Turin, from phosphate of ammonia and bichromate of potash, is that, besides being of a brilliant green, they maintain this colour by artificial light. In the month of November, 1859, the magenta colour, or fuchsine, of Messrs. Renard, was also introduced to the printing trade, and fixed by the above described method. The beautiful pinks thus obtained were soon followed by the application of roseine, azaléine, and other aniline reds. In May, 1859, a further improvement was made, which reduced the cost of applying these colours to muslins, by Mr Walter Crum, who made the curious observation that if the gluten of wheaten flour is allowed by exposure to the atmosphere to fall into a semifluid condition, it dissolves easily in a weak solution of caustic soda, which solution he used as a substitute for albumen or lactarine. About the same time, Mr. ScheurerKestner also introduced the use of gluten by the aid of weak acids, and Messrs. W. A. Perkin, and Matthew Gray, of the Dalmarnock Printing Company, proposed to fix the coal tar colours on fabrics by means of a lead soap.

Early in 1860 calico printers succeeded in printing the aniline colours directly with the animal mordaunts, instead of dyeing the mordaunts after the latter were printed and fixed, and thus were enabled not only to print a variety of colours on the same piece, but also to effect a great saving and simplicity in the operation. By this means the pigment style was fully developed, and an entirely new class of prints was introduced into this market.

Pigment Printing. This style remained for many years in a dormant condition, owing, first to the difficulty of finding a proper fixing agent, and then to the insufficient variety of pigments, for it was necessary to find a substance which would give the pigment the required consistency, and at the same time cause it to adhere to the cloth. Artificial ultramarine was the first pigment attempted to be printed, and in 1843 india-rubber dis- Owing to the great extension of this style, the cost of solved in naphtha was proposed as a fixing agent for it, the animal mordants employed became such a serious but owing to the danger of fire, and for other reasons, this consideration as to cause anxious search for other means method was abandoned. In 1847, egg albumen was in- of fixing the colours, and Mr. Charles Lowe and myself troduced into this country for the same purpose, but having observed in 1856 that tanning matters would preowing to the coarseness of the ultramarine, and its high cipitate and render insoluble certain coal-tar colours, and price, which was about £8 per lb. (it is now 1s. 3d.) the having further observed, at the end of 1859, that tannin, progress of this mode of printing was greatly retarded. when printed on cloth and submitted to the action of În 1849, Mr. R. T. Pattison, of Glasgow, patented the use steam would become fixed, and serve as a mordant for of caseine from milk, which he called lactarine, which the coal-tar colours, we took out a provisional specification promoted the use of ultramarine, buff, and stone pigments on the 10th of December, 1859, for fixing the insoluble in shawl printing. About the same period, another fixing tanning compound formed by adding a solution of gallagent was introduced, viz., albumen obtained from blood. nuts to a coal-tar colour, on cloth prepared with oxide of The style of pigment printing, however, received an extra-tin or alumina, or other metallic oxides. For various ordinary impetus in the spring of 1859, when the purple reasons this patent was not proceeded with, but in the aniline of Mr. Perkin was successfully introduced by early part of 1861 Mr. Gratrix, with the intelligent and Messrs. James Black and Co., of Glasgow, and the French persevering assistance of Messrs. Butterworth and Brooks, purple of Messrs. Guinon, Marnas, and Bonnet, of Lyons, of Manchester, succeeded in fixing aniline purples, which, by Messrs. Walter Crum and Co., Dalglish and Co., Boyd though faster against soap than those printed with albuand Hamel, Inglis and Wakefield, Heys, &c., and the men, did not so perfectly resist the action of light. The splendid mauves and purples which astonished the world first process used by Mr. Gratrix was, with very slight by their beauty, fastness, and brilliancy, were obtained by modification, the same as that described above, but his printing albumen or lactarine on muslin, and fixing the second process, which I think he preferred, was the folsame by coagulating it by the action of steam. The lowing:-He took cloth prepared with oxide of tin, such pieces were then passed into the dyebeck, containing in as is generally used for steam colours, and after having solution Mr. Perkin's aniline purple, or Messrs. Guinon, printed it with a gall-nut solution, submitted it to the Marnas, and Co.'s French purple, first dissolved in oxalic action of steam, when the tannin became fixed and inacid, and then added to a slightly ammoniacal bath, when soluble; the pieces were then passed through a dunging the albumen or lactarine took up the colour and fixed it on liquor, washed, and then into a beck containing aniline the cloth, the pieces being then thoroughly washed, to re-purple mixed with a little acetic acid. As the bath was move any excess of colour. In the middle of the same year, a beautiful green pigment, which had been patented in 1858 by Mr. Guignet, was introduced, and as it is extensively employed, it may be interesting to know how this green oxide of chrome is produced. Three parts of boracic acid are intimately mixed with one part of bichromate of potash and a sufficient quantity of water to form the whole into a thick paste. It is then introduced into a furnace, and heated to a dull red heat, when a borate of potash and a borate of oxide of chrome are produced. The mass is allowed to cool, and is then thrown into cold water, when the borate of potash dissolves, and the borate of oxide of chrome is decomposed. The hydrate of oxide of chromium, Cr, 0, +3HO, falls to the bottom as a magnificent green

gradually carried to the boil, the colour fixed itself on the tannin, and thus produced the print, but as the whites were rather soiled, the pieces were passed into a weak acid bath, or through a weak solution of printing clearing liquor, such as is used for garancine.

Early in 1860, Mr. John Lightfoot also took out a patent to fix colours, especially those from coal-tar, by various means, the chief of which was tannate of gelatine. In 1861 patents were secured by Messrs. Pattison, Miller, and Nathaniel Lloyd, and J. G. Dale. The last of these patents is, in my opinion, one of the best which have been taken out for that purpose, and is successfully worked by Messrs. Littlewood and Wilson, of Accrington. characteristic feature of this process is the employment of


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