These are perhaps due to the oil dropping on to the piece during the process of weaving when in the loom. The oils used for the lubrication of spinning and weaving machinery should contain a fair proportion of some fatty oil, such as olive or rape or cocoanut oil. Not less than 10 per cent. should be used. More would be better, but the cost of course would be greater and oil is an item with spinners and manufacturers.

Stains are occasionally due to other causes rather too numerous to be dealt with in detail, and sometimes these stains only appear once in a lifetime, and often do not make their appearance during the bleaching process, but only in after dyeing or calico printing processes in curious ways the causes of which are very baffling to find out.



CHAPTER III.

DYEING MACHINERY AND DYEING MANIPULATIONS.

Cotton is dyed in a variety of forms: raw, loose cotton, partly manufactured fibre in the form of slubbing or sliver, spun fibres or yarns wound in cop or bobbin forms, in hanks or skeins and in warps, and lastly in the form of woven pieces. These different forms necessitate the employment of different forms of machinery and different modes of handling; it is evident to the least unobservant that it would be quite impossible to subject slubbing or sliver to the same treatment as yarn or cloth, otherwise the slubbing would be destroyed and rendered valueless.

In the early days all dyeing was done by hand in the simplest possible contrivances, but during the last quarter of a century there has been a great development in the quantity of dyeing that has been done, and this has really necessitated the application of machinery, for hand work could not possibly cope with the amount of dyeing now done. Consequently there has been devised during the past two decades a great variety of machines for dyeing every description of textile fabrics, some have not been found a practical success for a variety of reasons and have gone out of use, others have been successful and are in use in dye-works.

HAND DYEING.



Dyeing by hand is carried on in the simplest possible appliances; much depends upon whether the work can be done at the ordinary temperature or at the boil. Figs. 6 and 7 show respectively a rectangular vat and a round tub much in use in dye-houses. These are made of wood, but copper dye-vats are also made. These may be used for all kinds of material, loose fibre, yarns or cloth. In the case of loose fibre this is stirred about either with poles or with rakes, care being taken to turn every part over and over and open out the masses of fibre as much as possible in order to avoid matting or clotting together. In the case of yarns or skeins, these are hung on sticks resting on the edges of the tub or vat. These sticks are best made of hickory, but ash or beech or any hard wood that can be worked smooth and which does not swell much when treated with water may be used. The usual method of working is to hang the skein on the stick, spreading it out as much as possible, then immerse the yarn in the liquor, lift it up and down two or three times to fully wet out the yarn, then turn the yarn over on the stick and repeat the dipping processes, then allow to steep in the dye-liquor. This is done with the batch of yarn that is to be dyed at a time. When all the yarn has been entered into the dye-bath, the first stickful is lifted out, the yarn turned over and re-entered in the dye-liquor, this operation is carried out with all the sticks of yarn until the cotton has become dyed of the required depth. In the case of long rectangular vats it is customary for two men, one on each side of the vat to turn the yarns, each man taking charge of the yarn which is nearest to him. The turning over one lot of yarn is technically called "one turn" and the dyer often gives "three turns" or "four turns" as may be required.

Woven goods may be dyed in the tub or vat, the pieces being drawn in and out by poles, but the results are not altogether satisfactory and it is preferable to use machines for dyeing piece goods.



Plain tubs or vats, such as those shown in Figs. 6 and 7, are used for dyeing, and otherwise treating goods in the cold, or at a lukewarm heat, when the supply of hot water can be drawn from a separate boiler. When, however, it is necessary to work at the boil, then the vat must be fitted with a steam coil. This is best laid along the bottom in a serpentine form. Above the pipe should be an open lattice-work bottom, which, while it permits the free circulation of boiling water in the vat, prevents the material being dyed from coming in contact with the steam pipe. This is important if uniform shades are to be dyed, for any excessive heating of any portion of the bath leads to stains being produced on the material in that part of the bath. Fig. 8 shows a vat fitted with a steam pipe. That portion of the steam pipe which passes down at the end of the vat is in a small compartment boxed off from the main body of the vat, so that no part of the material which is being dyed can come in contact with it. A closed steam coil will, on the whole, give the best results, as then no weakening of the dye-liquor can take place through dilution by the condensation of the steam. Many dye-vats are, however, fitted with perforated, or, as they are called, open steam coils, in which case there is, perhaps, better circulation of the liquor in the dye-vat, but as some of the steam must condense, there is a little dilution of the dye-liquor in the vat.

DYEING MACHINES.

Dye tubs and vats, such as those described above, have been largely superseded by machines in which the handling, or working of the materials being dyed is effected by mechanical means. There have been a large number of dyeing machines invented, some of these have not been found to be very practical, and so they have gone out of use. Space will not admit of a detailed account of every kind of machine, but only of those which are in constant use in dye-works.

Dyeing Loose, or Raw Cotton.—Few machines have been designed for this purpose, and about the only successful one is:

Delahunty's Dyeing Machine.—This is illustrated in Fig. 9. It consists of a drum made of lattice work, which can revolve inside an outer wooden casing. The interior of the revolving drum is fitted with hooks or fingers, whose action is to keep the material open. One segment of the drum is made to open, so that the loose cotton or wool to be dyed can be inserted. By suitable gearing the drum can be revolved; and the dye-liquor, which is in the lower half of the wooden casing, penetrates through the lattice work of the drum, and dyes the material contained in it. The construction of the machine is well shown in the drawing, while the mode of working is obvious from it and the description just given. The machine is very successful, and well adapted for dyeing loose, or raw wool and cotton. The material may be scoured, bleached, dyed, or otherwise treated in this machine.

The Obermaier machine, presently to be described, may also be used for dyeing loose cotton or wool.

DYEING, SLUBBING, SLIVER OR CARDED COTTON AND WOOL.



It is found in practice that the dyeing of loose wool or cotton is not altogether satisfactory—the impurities they naturally contain interfere with the purity of the shade they will take. Then again the dyes and mordants used in dyeing them are found to have some action on the wire of the carding engine through which they are passed; at any rate a card does not last as long when working dyed cotton or wool as when used on undyed cotton or wool fibres. Yet for the production of certain fancy yarns for weaving some special classes of fabrics, it is desirable to dye the cotton or wool before it is spun into thread. The best plan is undoubtedly to dye the fibre after it has been carded and partly spun into what is known as slubbing or sliver. All the impurities have been removed, the cotton fibres are laid, straight, and so it becomes much easier to dye. On the other hand, as it is necessary to keep the sliver or slubbing straight and level, no working about in the dye-liquors can be allowed to take place, and so such must be dyed in specially constructed machines, and one of the best of these is the Obermaier dyeing machine which is illustrated in Fig. 10. The Obermaier apparatus consists of a dye vat A. In this is placed a cage consisting of an inner perforated metal cylinder C, and an outer perforated metal cylinder D, between these two is placed the material to be dyed. C is in contact with the suction end of a centrifugal pump P, the delivery end of which discharges into the dye-vat A. The working of the machine is as follows: The slubbing or sliver is placed in the space between C and D rather tightly so that it will not move about. Then the inner cage is placed in the dye-vat as shown. The vat is filled with the dye-liquor which can be heated up by a steam pipe. The pump is set in motion, the dye liquor is drawn from A to C, and, in so doing, passes through the material packed in B and dyes it. The circulation of the liquor is carried on as long as experience shows to be necessary. The dye-liquor is run off, hot water is run in to wash the dyed material, and the pump is kept running for some time to ensure thorough rinsing; then the water is run off, and by keeping the pump running and air going through a certain amount of drying can be effected. This machine works very well, and, with a little experience, constant results can be obtained. The slubbing or sliver may be scoured, bleached, rinsed, dyed, washed, soaped, or otherwise treated without removing it from the machine, which is a most decided advantage.



Holliday's Yarn-dyeing Machine.—In Fig. 11 is given an illustration of a machine for dyeing yarn in the hank form made by Messrs. Read Holliday & Sons, of Huddersfield. The illustration gives a very good idea of the machine. It consists of a wooden dye-vat which can be heated by steam pipes in the usual way. Extending over the vat are a number of reels or bobbins; these are best made of wood or enamelled iron; these reels are in connection with suitable gearing so that they can be revolved. There is also an arrangement by means of which the reels can be lifted bodily in and out of the dye-vat for the purpose of taking on and off, "doffing," the hanks of yarn for the reels. A reel will hold about two pounds of yarn. The working of the machine is simple. The vat is filled with the requisite dye-liquor. The reels, which are lifted out of the vat, are then charged with the yarn, which has been previously wetted out. They are then set in revolution and dropped into the dye-vat and kept there until it is seen that the yarn has acquired the desired shade. The reels are lifted out and the hanks removed, when the machine is ready for another lot of yarn.

There are several makes of hank-dyeing machines of this type, and as a rule they work very well. The only source of trouble is a slight tendency for the yarn on one reel if hung loosely of becoming entangled with the yarn on one of the other reels. This is to some extent obviated by hanging in the bottom of the hank a roller which acts as a weight and keeps the yarn stretched and so prevents it flying about.

To some makes of these machines a hank wringer is attached.



Klauder-Weldon Hank-dyeing Machine.—This is illustrated in Fig. 12, which shows the latest form. This machine consists of a half-cylindrical dye-vat built of wood. On a central axis is built two discs or rod carriers which can revolve in the dye-vat, the revolution being given by suitable gearing, which is shown at the side of the machine. On the outer edge of the discs are clips for carrying rods, on which one end of the hanks of yarn is hung, while the other end is placed on a similar rod carried near the axle. The revolution of the discs carries the yarn through the dye-liquor contained in the lower semi-cylindrical part of the machine previously alluded to. At a certain point, every revolution of the discs, the rods carrying the yarns are turned a little; this causes the yarn to move on the rods, and this motion helps to bring about greater evenness of dyeing. The most modern form of this machine is provided with an arrangement by means of which the whole batch of yarn can be lifted out of the dye-liquor. Arrangements are made by which from time to time fresh quantities of dye can be added if required to bring up the dyed yarn to any desired shade. This machine works well and gives good results. Beyond the necessary labour in charging and discharging, and a little attention from time to time, as the operation proceeds, to see if the dyeing is coming up to shade, the machine requires little attention.

Many other forms of hank-dyeing machines have been devised: there is Corron's, in which an ordinary rectangular dye-vat is used. Round this is a framework which carries a lifting and falling arrangement that travels to and fro along the vat. The hanks of yarn are hung on rods of a special construction designed to open them out in a manner as nearly approaching handwork as is possible. The machine works in this way: the lifting arrangement is at one end of the vat, the hanks are hung on the rods and placed in the vat. Then the lifter is set in motion and moves along the vat; as it does so it lifts up each rod full of yarn, turns it over, opening out the yarn in so doing, then it drops it again in the vat. When it has travelled to the end of the vat it returns, picking up the rods of yarn in so doing, and this motion is kept up until the dyeing is completed. This machine is very ingenious.

A type of machine which has been made by several makers consists of an ordinary rectangular dye-vat surrounded with a framework carrying a number of sets of endless chains, the links of which carry fingers. The hanks of yarn are hung on rods at one end of which is a tooth wheel that when in position fits into a rack on the side of the vat. The action of the machine is this: the hanks are hung on the rods and placed at the entrance end of the vat, by the moving of the chains it is carried along the vat and at the same time revolves, thus turning over the yarn which hangs in the dye-liquor; when it reaches the opposite end of the vat, the rod full of yarn is lifted out, carried upwards and then towards the other end of the vat when it is again dropped into the dye-vat to go through the same cycle of movements which is continued until the yarn is properly dyed.

COP DYEING.

In weaving fancy-coloured fabrics the ordinary mode is to dye the yarn in the hank form, then those which have to be used for the weft are wound into the cop form for placing in the shuttles. The cop form is that in which the yarn leaves the spinning frame, and necessarily apart from the dyeing there is labour involved in reeling it into hanks and winding it back again into the cop form, not only so but there is necessarily some waste made in these operations. Many attempts have been made, with more or less success, to dye the yarn while in the cop form and so save the cost of the hanking and copping above referred to as well as the waste which occurs. Cops cannot be satisfactorily dyed by simple immersion in a boiling dye-bath, the outside becomes dyed but the central portions as often as not remain quite white, and there is a distinct grading of colour or shade throughout the cop, the outer portions being deeply dyed while the middle portion will only have a medium shade and the central portions either not being dyed at all or only faintly tinted, much depending on the firmness with which the cop has been wound. A soft, loosely wound cop is much more thoroughly dyed than a hard, tightly wound cop. This uneven dyeing of the cops is not satisfactory, and must be avoided if cop dyeing is to be a success. Many dyers have turned their attention to this question of dyeing yarn in the cop form, and many machines have been devised for the purpose; some of these have not been a success, but a few have been found to yield satisfactory results and proved in practice very successful.

In all machines for dyeing cops one principle has been adopted—that of drawing or forcing the dye-liquor through the cop.



Graemiger's Cop-dyeing Machine.—This is shown in section in Figs. 13 and 14. Although simple in its work it is somewhat complex in its construction and difficult to describe. The machine consists of a dye-vat to hold the requisite dye-liquors. In the upper portions of this is an iron casting formed with four chambers, the two lower ones of which are immersed in the dye-liquor while the upper chambers are above it. The sides of this casting are formed of metal plates which fit tightly against the casting and form as nearly air-and water-tight joints with it as it is possible to make. These metal plates are on a spindle and can be rotated. They are perforated and made to carry spindles, on which are placed the cops to be dyed. The two lower chambers are in connection with a pump which draws the air from them and so creates a vacuum inside the chambers. To fill this, liquor from the dye-vat passes through the cops and into the chambers, and is in turn drawn through the pump and returned to the dye-vat. In this way there is a continual circulation of dye-liquors from the vat through the cops, chambers and pump back to the vat again.



The left upper chamber is practically a blank chamber. Those portions of the cop carriers in contact with it are filled with cops, which are placed on perforated spindles; the discs are given a quarter revolution which brings the cops into the dye-liquor and in connection with the left lower chamber and are dyed. At the same time the section of the cop carriers now in contact with the left top chamber is filled with a new lot of cops, another quarter of a revolution is given to the cop carriers, which immerse the new lot of cops in the dye-liquor. The third quarter of the cop plates is filled with cops. A third movement of the cop plates now takes place; this brings the first lot of cops out of the dye-liquor and in contact with the right upper chamber, where the surplus liquor is drawn out of them and returned to the dye-vat. Another revolution brings the cops back to their first position, they are now removed and a new lot substituted. These proceedings go on continuously. Although not quite free from defects the machine gives very good results, the cops being very uniformly dyed through.



Beaumont's Cop-dyeing Machine.—This is illustrated in Fig. 15. It consists of a copper hemispherical dye-vessel, which is provided with a tightly fitting lid, although this is not needed in all cases. The bottom of the vessel is in communication with the suction end of a centrifugal pump, while the delivery end of the pump is attached to the upper end of the dye-vessel, the action of the pump being to secure a constant circulation of dye-liquor from the bottom to the top of the dye-vessel. Arrangements are provided by a peculiar and ingenious contrivance fitted in one side of the dye-kettle for introducing steam to heat the dye-liquor to any required degree. As in most forms of cop-dyeing machines, the cops are placed on perforated metal spindles. The cops and spindles are inserted in holes in a perforated metal plate, and over them is placed a thin metal plate, technically called the antifloater, whose object is to prevent the cops from becoming detached from the plate. This plate, full of cops, is now placed in the dye-vessel and rests upon a flange which is provided for that purpose. When the cop plate is in position the dye-vessel is divided into two chambers—a lower chamber and an upper one, in the latter being the cops.

The pump draws liquor from the chamber under the cop plate and so creates a vacuum, which during the working of the machines ranges from 10 to 20 inches in degree. To supply this vacuum, dye-liquor is drawn from the upper chamber through the cops. The pump returns the liquor to the dye-vessel. A very rapid circulation of dye-liquor takes place, from 25 to 50 gallons per minute passing through the cops and pump. From five to ten minutes is sufficient to dye the cops. The machine is simple in its construction and gives good results, the cops being completely dyed through. One important consideration in cop dyeing is to be able to dye successive batches of cops to exactly the same shade, and this is quite possible with this machine.

Young & Crippin's Cop-dyeing Machine.—So far as simplicity of construction is concerned this lies between the two preceding machines. It consists of four parts with some accessory mechanism. There is first a dye-liquor storage tank at the base of the apparatus in which the liquor is kept stored and boiling (if necessary) ready for use, above this and at the front end is the dye-chamber, this communicates at its lower end by a pipe with the dye-liquor in the dye-vat. Then there is a large vacuum chamber, in which by means of an injector a vacuum can be formed, this directly communicates with a liquor-receiving chamber which again in turn is in communication with the upper part of the dye-chamber. The cops are placed on perforated spindles as usual, and these on a perforated plate and are kept in place by a plate which is screwed down on them. The charged cop plate is placed in the dye-chamber on which a cover is placed and screwed down. By means of a lever the injector is set at work, a vacuum created in the vacuum and receiving chambers, the consequence being that dye-liquor is drawn from the vat through the cops in the dye-chamber into the receiving chamber. When a certain quantity of liquor has passed through, by a movement of a lever, the vacuum is destroyed, and the dye-liquor runs back into the dye-vat; these operations are repeated until from past experience of the working of the machine it is thought sufficient has passed through to dye the cops, when the dye-chamber is opened and the cops taken out. This machine works very well.

Mommer's Cop-dyeing Machine.—This is in use in several continental dye-works. The central portion of this machine is a rectangular dye-chamber, which can be hermetically closed by hinged doors, the cops are placed side by side on trays provided with perforated bottoms, the trays being placed one on the top of the other in the dye-chamber. From the top of the dye-chamber passes a pipe to a centrifugal pump, and a similar pipe passes from the bottom of the chamber to the pump. A separate vat contains the dye-liquor which is used. The pump forces the dye-liquor through the cops which take up the dye. Arrangements are provided by which the direction of the flow of the dye-liquor can be changed. This machine gives fairly good results, not perhaps equal to those with the machines previously described.

Warp-dyeing Machines.—Although many warps, especially for fancy fabrics, are prepared from yarns dyed in the hank or cop form, yet it is found advantageous when a warp is of one colour, a self-colour as it is called, to form the warp from grey or white yarns and to dye it after warping. If the warp were so wound as to be able to go into a Obermaier dyeing machine, it would be possible to dye it in that machine, but generally warps are dyed in the open form and are passed through a dyeing vat, commonly called a warp-vat which is constructed as shown in Fig. 16. These warp-dyeing machines generally consist of a long rectangular wooden dye-vat, divided by two partitions into three compartments, each provided with steam pipes to heat up its contents; between the first and second and between the second and third compartments is fitted a pair of squeezing rollers, while the third compartment is fitted with a heavier pair of squeezing rollers. Motion is given to these rollers by suitable gearing, and they serve to draw the warp through the machine. Guide rollers are fitted in the compartment, and the warp being taken round these, it passes several times up and down and through the dye-liquors contained in the compartments. These warp-dyeing machines may be made of sufficient width to take one, two, three or more warps at one time as desired.



The three compartments of the machine may contain different liquids or all the same liquid according as the nature of the shade to be dyed demands. The passage is done slowly so as to give the warp time to absorb the liquors and take up the dye. When all the length of warp has been sent through, it is said to have been dyed "one end". Sometimes this will be enough, but often it is not, and so the warp is sent through again, given another end, and still again if the full shade has not been attained.

After being dyed in this machine the warp is sent through another one containing various wash liquors to finish the process.



Fig. 17 shows a warp-dyeing machine similar to, but a little more elaborate in construction than, the vats just described.

Piece-dyeing Machines.—Wherever it is possible it is far more preferable to dye textile fabrics in the form of woven pieces rather than in the yarn from which they are woven. During the process of weaving it is quite impossible to avoid the material getting dirty and somewhat greasy, and the operations of scouring necessary to remove this dirt and grease has an impairing action on the colour if dyed yarns have been used in weaving it. This is avoided when the pieces are woven first and dyed afterwards, and this can always be done when the cloths are dyed in one colour only. Of course when the goods are fancy goods containing several colours they have to be woven from dyed yarns.



The most common form of machine in which pieces are dyed is The Jigger, commonly called the jig. This is shown in Figs. 18 and 19. It consists of a dye-vessel made sufficiently long to take the piece full width—wide at the top and narrow at the bottom. At the top at each side is placed a large winding roller on which the cloth is wound. At the bottom of the jig is placed a guide roller round which passes the cloth. In some makes of jigs (Fig. 19) there are two guide rollers at the bottom and one at the top, as shown in the illustration, so that the cloth passes several times through the dye-liquor. In working, the cloth is first wound on one of the rollers, then threaded through the guide rollers and attached to the other winding roller. When this is done dye-liquor is run into the jig, the gearing set in motion, and the cloth wound from the full on to the empty roller. With the object of keeping the piece tight, a heavy press roller is arranged to bear on the cloth on the full roller. When all the cloth has passed from one roller to the other it is said to have been given "one end". The direction of motion is now changed, and the cloth sent in the opposite direction through the jig, and the piece has now received another "end". This alternation from one roller to the other is continued as long as is deemed necessary, much depending on the depth of colour which is being dyed—some pale shades may only take two or three ends, deeper shades may take more. When dyeing wool with acid colours which are all absorbed from the dye-liquor, or the bath is exhausted, it is a good plan to run the pieces several more ends so as to ensure thorough fixation of the dye on the cloth.

It is not advisable in working these jigs to add the whole of the dye to the liquor at the commencement, but only a part of it; then when one end is given, another portion of the dye may be added; such portions being always in the form of solution. Adding dyes in powder form inevitably leads to the production of colour specks on the finished goods. The reason for thus adding the dye-stuff in portions is that with some dyes the affinity for the fibre is so great that if all were added at once it would all be absorbed before the cloth had been given one end; and, further, the cloth would be very deep at the front end, while it would shade off to no colour at the other end. By adding the dye in portions this difficulty is overcome and more level shades are obtained; it is met with in all cases of jigger dyeing, but it is most common in dyeing cotton or wool with basic dyes like magenta, auramine, methyl violet or brilliant green, and in dyeing wool with acid dyes like acid green, formyl violets, azo scarlet, or acid yellow.

Some attempts have been made to make jiggers automatic in their reversing action, but they have not been successful; owing to the greatly varying conditions of length of pieces, their thickness, etc., which have to be dyed, and it is next to impossible to make all allowances for such varying conditions.



The Jig Wince or Wince Dye Beck.—This dyeing machine is very largely used, particularly in the dyeing of woollen cloths. It is made by many makers, and varies somewhat in form accordingly. Figs. 20, 21 and 22, show three forms by different makers. In any make the jig wince, or wince dye beck, consists of a large rectangular, or, in some cases, hemicylindrical dye-vat. Probably the best shape would be to have a vat with one straight side at the front, and one curved side at the back. In some a small guide roller is fitted at the bottom, under which the pieces to be dyed pass. Steam pipes are provided for heating the dye-liquors. The becks should be fitted with a false bottom made of wood, perforated with holes, or of wooden lattice work, and below which the steam pipes are placed; the object being to prevent the pieces from coming in contact with the steam pipe, and so preventing the production of stains. Above the dye-vat, and towards the back, is the wince, a revolving skeleton wheel, which draws the pieces out of the dye-vat at the front, and delivers them into it again at the back. The construction of this wince is well shown in the drawings. The wince will take the pieces full breadth, but often they are somewhat folded, and so several pieces, four, five or six strings as they are called, can be dealt with at one time. In this case a guide rail is provided in the front part of the machine. In this rail are pegs which serve to keep the pieces of cloth separate, and so prevent entanglements. The pieces are stitched end to end so as to form an endless band. When running through the vat they fall down in folds at the back part of the beck, and are drawn out of the bottom and up in the front. Each part thus remains for some time in the dye-liquor, during which it necessarily takes up the dye.



In the jig and wince dyeing machines the pieces necessarily are for a part of the time, longer in the case of the jigger than in that of the wince, out of the dye-liquor and exposed to the air. In the case of some dyes, indigo especially, this is not desirable, and yet it is advisable to run the cloth open for some time in the liquor, so as to get it thoroughly impregnated with the dye-liquor, or to become dyed. This may be done on such a machine, as is shown in Fig. 24, page 79, but having all the guide rollers below the liquor, so that at no time is the piece out of the liquor, except, of course, when entering and leaving.



The so-called hawking machines have also this object in view, and Fig. 23 is an illustration of Holliday's hawking machine, made by Messrs. Read Holliday & Sons, of Huddersfield. There is the dye-vat as usual; in this is suspended the drawing mechanism, whose construction is well shown in the drawing. This is a pair of rollers driven by suitable gearing, between which the cloth passes, and by which it is drawn through the machine. A small roller ensures the cloth properly leaving the large rollers; then there is a lattice-work arrangement over which the pieces are drawn. In actual work the whole of this arrangement is below the surface of the dye-liquor in the vat. The piece to be dyed is threaded through the machine, the ends stitched together. Then the arrangement is lowered into the dye-vat and set into motion, whereby the cloth is drawn continuously in the open form through the dye-liquor, this being done as long as experience shows to be necessary. This hawking machine will be found useful in dyeing indigo on cotton or wool, or in dyeing cotton cloths with such dyes as Immedial blacks, Cross-dye blacks, Amidazol blacks, Vidal blacks, where it is necessary to keep the goods below the surface of the dye-liquor during the operation.



Fig. 24 shows a form of cloth-dyeing machine much used in the cotton trade. It consists of a number of compartments fitted with guide rollers at top and bottom, and round which the cloth is threaded, so that it passes up and down in the dye-liquor several times. Between each two compartments is a pair of squeezing rollers to press out all surplus liquors. All the compartments may be filled with the same dye-liquor, or with different dye-liquors and developing liquors, as may be most convenient and required for the work in hand. Such a machine is used in dyeing logwood black, aniline black, and many of the direct colours, etc.

From the direct colours a large number of light shades are dyed on to cotton cloth by the process known as padding; this consists in passing the cloth through a liquor containing the dye-stuff, usually a little phosphate of soda is added, then between squeezing rollers, and finally drying the cloth. For this process there is used what is called a padding machine. This is shown in Figs. 25 and 26.



It consists essentially of a trough, which contains two or more guide rollers, and in this is placed the padding liquor. Above the trough is fitted squeezing rollers, sometimes two as in Fig. 25, or three as in Fig. 26. Besides these, there are winding and beaming and other guide rollers. Fig. 25 shows the simplest padding machine, where the cloth passes once through the liquor and through the squeezing rollers. In Fig. 26 the cloth passes several times through the liquor and twice through the squeezing rollers, thus ensuring a more perfect impregnation of the cloth with the dye-liquor, and therefore a more uniform dyeing of the cloth.



CHAPTER IV.

THE PRINCIPLES AND PRACTICE OF COTTON DYEING.

Students of cotton dyeing should have a good knowledge of the principles that underlie the processes of dyeing cotton fabrics. It is only by recognising these principles and then endeavouring to apply them to each individual case of dyeing, that the dyer or student will obtain a thorough grasp of his subject. It is the aim of the author to lay down these principles in a clear and intelligible form. Cotton is dyed in its loose raw condition, as yarn in the form of hanks, yarn in the form of cops, and in the woven pieces of every kind. Formerly the idea was prevalent among cotton dyers that the process which succeeds with piece goods would not answer with yarns. It is now recognised however that this is not so, that a process which will dye cotton yarn will also dye cotton piece goods or loose cotton. The differences which do exist in the practical working of the processes entirely arise from the difference in the form in which the cotton is presented to the dyer, for it must be obvious to any one that the mode of handling a piece of cotton cloth during the time it is in the dye-bath must be different from that of a hank of yarn, a parcel of loose cotton or a number of cops. The various machines used for dyeing all these forms and the manner of working them have been already described.

The dyes, whether natural—derived from the various dye-woods, etc.—or artificial—prepared from coal tar—may according to their varied chemical composition and constitution be divided into seventeen or eighteen distinct groups, but it is not intended here to give any account of them; the reader is referred to other books such as The Dictionary of Coal Tar Colours, by George H. Hurst; The Chemistry of Coal Tar Colours, by Benedikt and Knecht; or The Chemistry of Organic Colouring Matters, by Nietzki, where the composition and properties of the dyes are fully described.

From the manner in which the various dyes are applied to cotton, linen, wool and other fibres we can divide them into five groups, thus:—

Group 1. Direct dyes. " 2. Basic dyes. " 3. Acid dyes. " 4. Mordant dyes. " 5. Miscellaneous dyes.

First group, direct dyes, are now very numerous; they dye cotton, linen and other vegetable fibres from a plain bath, and do not require those fibres to be prepared in any way. Hence the reason of their being named direct, or by some the substantive colours. They will also dye wool and silk.

The second group, basic dyes, comprise some of the oldest of the coal-tar dyes; they dye wool and silk direct from plain baths, but require cotton, linen and other vegetable fibres to be previously prepared in baths of tannic acid, sumach or other tanning material.

The third group, acid dyes, are very numerous, and from both their chemical composition and mode of dyeing can be divided into several sub-groups. Their principal feature is that they dye wool and silk from baths containing Glauber's salt and some acid, hence their name of "acid dyes". They do not dye cotton or linen well, some not at all, others are absorbed to a slight extent by the cotton, but only pale tints are produced, while others may be used along with metallic mordants to dye bright but pale and fugitive shades. The acid dyes comprise such as Acid green, Formyl violet, Acid magenta, Azo scarlet, Orange. Thiocarmine R., Patent blues, Wool greens, indigo extract, Eosines, etc.

The fourth group, mordant dyes, includes the alizarine series of coal-tar colours, logwood, Brazil wood and most natural colours, and some others. The principal feature of these dyes is that they require the cotton to be prepared with some metallic oxide, like those of chrome, alumina and iron, before dyeing, and the colour which is got depends partly upon the particular dye-stuff used and partly upon the oxide with which the cotton has been prepared.

The fifth group includes a few dyes like indigo, which are dyed on to cotton by various and special processes.

The processes of cotton dyeing employed to-day may be comprised under eight heads, namely:—

(1) Direct dyeing. (2) Direct dyeing followed by fixation with metallic salts. (3) Direct dyeing followed by fixation with developers. (4) Direct dyeing followed by fixation with couplers. (5) Dyeing on tannic mordant. (6) Dyeing on metallic mordant. (7) Developing the colour direct on fibre. (8) Dyeing by impregnating the cotton with the dye-stuff, followed by oxidation or steaming.

It is of course not easy to elaborate a simple scheme of grouping the processes that shall definitely include all processes, but the above grouping will be found as successful as any, and each will be considered as fully as is deemed necessary.

(1) DIRECT DYEING.

Nothing in the history of cotton dyeing caused such a revolution in the methods of working as did the introduction some fifteen years ago of the forerunners (Congo red, Benzo purpurine, Chrysamine, Azo blue) of the now numerous group of direct dyes, followed as they were by the Benzo, Congo, Diamine, Titan, Chicago and Zambesi members of the group. Prior to their introduction cotton dyeing was always more or less complicated and mordanting methods had to be employed.

With the introduction of the direct dyes cotton dyeing has become even more simple than wool or silk dyeing, and now all that is necessary is to prepare a dye liquor containing the necessary amount of dye-stuff and Glauber's salt, or common salt or soda, or some similar body, or a combination thereof. The method of working is to place the cotton in a lukewarm or even in a hot bath, raise to the boil, allow the goods to remain in the boiling bath for half an hour to an hour, then take them out, wring, wash and dry. This method is simple and will answer for all the dyes of this group. There are some that do not require the working to be done boiling; it is simply needful to enter the cotton into a boiling bath and work without steam until the bath has cooled down. Furious boiling is not needed—a gentle simmer gives the best results. Uneven dyeing seems to be an impossibility in this group of dyes, unless the cotton is dirty; no matter how the operations are carried on, level dyeing is the rule not the exception. An enormous variety of shades and tints can be obtained from these dyes, and they can be combined together in every conceivable manner and proportions.

No satisfactory explanation has yet been given as to what feature in the chemical composition of these dye-stuffs give them such an affinity for the cotton fibre as to enable them to dye in so simple a manner such fast shades as they do; it is a fact there is such an affinity and there the matter must rest.

It has been found in practice that the efficiency of the dyeing operation depends, primarily of course, on the particular dye-stuff used, but also upon other factors, that a certain assistant be used. Some dyes work on the cotton better from a bath containing Glauber's salt, while with others common salt works best, while a little soda along with the salt facilitates the dyeing in some cases. It is practically impossible to specify here the best assistant for all the direct colours, on account of the great number of such dyes which are known, but in the practical recipes given below much useful advice will be found. Then the quantity of such assistants used is of much importance; there is one proportion at which the best results are obtained for each dye. The dyer should find out for himself by experiment and the use of the dyes he employs in his work what assistant and how much is best, and make his baths up to that strength. With some dyes 10 per cent. of the assistant will be found sufficient, while with others, 25 to 30 per cent. will not be too much. The percentage refers to the weight of the cotton that is taken.

One function of the assistants must be pointed out here: it is that in some cases they—especially the alkaline ones, soda, potash, borax, phosphate of soda—help the dyeing by promoting the solubility of the dye-stuff in the bath, thereby retarding the exhaustion of the bath and ensuring the production of level shades.

The following formulas show the application of the foregoing principles to the dyeing of numerous shades on to cotton and also the dyes which are applicable, some of the combinations which are possible with these direct dyes, and give some idea of the tints and shades of the colours that can be got by their means. The best assistants to use are also indicated in the formulae.

All the formulae here given and all that will be given in future chapters are intended for 100 lb. weight of cotton fabrics in any condition, whether of loose cotton, yarn in cops, hanks or wraps and woven fabrics of every kind.

Bright Red.—Dye with 3 lb. Benzo purpurine 4 B, 3 lb. soda and 15 lb. Glauber's salt. This dye may also be used with 3 lb. soap and 10 lb. soda in the bath with equally good results.

Pale Salmon.—Prepare a dye-bath with 3 lb. salt, 5 lb. phosphate of soda, 1 lb. soap, 1/2 oz. Benzo orange R. For a pale shade like this it is not necessary to heat to the boil, a temperature of 170 deg. to 180 deg. F. is sufficient.

Dark Plum.—Prepare a dye-bath with 20 lb. of Glauber's salt, 2-1/2 lb. soap, 1-1/2 lb. Diamine black R O. and 2 lb. Diamine red N. Enter at 180 deg. F., work for a few minutes, then raise to boil and dye to shade; lift, wash and dry.

Turkey Red.—Prepare a dye-bath with 1-1/2 lb. Benzo purpurine 4 B, 1 lb. Brilliant purpurine, 2 lb. soap, 10 lb. borax. Enter the cotton at the boil and work for one hour; lift, wash and dry.

Lilac Red.—Prepare the dye-bath with 2 lb. soap, 5 lb. soda, 3 lb. Rose azurine G. Work at the boil for one hour.

Pink.—Prepare a bath containing 10 lb. soda, 1 oz. Rose azurine B. Enter at a boil and work for one hour, boiling to shade; lift, wash and dry.

Bordeaux.—Prepare a dye-bath with 15 lb. Glauber's salt, 5 lb. soda crystals, 3 lb. Diamine fast red F, 1 lb. Diamine violet N, 1 lb. Rose azurine G. Enter cold, then raise to the boil, and work for one and a half hours; lift, wash and dry.

Rose Pink.—The dye-bath is made with 2 lb. Erika B, 20 lb. Glauber's salt and 3 lb. soap, working at near the boil to shade.

Brilliant Red.—Make the dye-bath with 24 lb. Brilliant purpurine R and 25 lb. Glauber's salt, working at the boil for one hour.

Deep Pink.—Make the dye-bath with 1/2 lb. Diamine rose B D, 1/2 lb. soda, 1 lb. soap and 5 lb. Glauber's salt, working at 150 deg. F. for half an hour.

Dark Red.—Use in the dye-bath 3 lb. Diamine red 5 B, 2 lb. soda and 20 lb. Glauber's salt, working at the boil for one hour.

Pink.—Prepare the dye-bath with 4 oz. Diamine rose B D, 1 lb. Turkey-red oil, 40 lb. Glauber's salt. Dye at the boil for one hour.

Scarlet.—Prepare the dye-bath with 4 lb. Diamine scarlet 3 B, 1 lb. Turkey-red oil, 20 lb. Glauber's salt. Dye at the boil for one hour.

Scarlet.—Prepare the dye-bath with 3 lb. Titan scarlet C, 1/2 lb. Titan orange, 50 lb. salt. Work at the boil for thirty minutes, then lift, wash and dry. The dye-bath is not exhausted and may be used for further lots.

Crimson Red.—Prepare the dye-bath with 5 lb. Titan scarlet D and 50 lb. salt. Work at the boil for fifty minutes, then lift, wash and dry. The bath is not exhausted, the cotton taking up only about 3 lb. of the dye-stuff; it may therefore be kept for further use, when for each succeeding lot 3 to 3-1/2 lb. of colour and 25 lb. of salt only need be added.

Scarlet.—Prepare the dye-bath with 5 lb. Rosophenine 5 B, dissolved in 50 gallons hot water, 2 gallons caustic soda lye (60 deg. Tw.). When thoroughly dissolved add 150 lb. salt. Make up the bath to 100 gallons. Enter the yarn and work for a quarter to half an hour at about 180 deg. F; squeeze off and wash thoroughly in cold water until the water runs off clean.

Rose Red.—Use 1 lb. Diamine red 10 B, 3 lb. soda, and 20 lb. Glauber's salt.

Deep Crimson.—Use 3 lb. Diamine red 10 B, 3 lb. soda and 20 lb. Glauber's salt.

Claret.—Use 3 lb. Diamine Bordeaux B, 3 lb. soda and 20 lb. Glauber's salt.

Pink.—The dye-bath is made with 5 oz. Dianil red 4 B, 5 lb. salt and 3 lb. soda.

Scarlet.—Use in the dye-bath 3 lb. Dianil red 4 B, 15 lb. salt and 5 lb. soda. Work at the boil for one hour.

Claret.—Dye with 1-1/2 lb. Dianil claret G, 3 lb. soda and 20 lb. salt. Work at the boil for one hour.

Maroon.—Dye with 3 lb. Dianil claret B, 3 lb. soda and 20 lb. salt. Work at the boil for one hour.

Bright Scarlet.—Use in the dye-bath 2-1/2 lb. Dianil red 4 B 5 oz. Dianil orange G, 3 lb. soda and 15 lb. salt.

Dark Maroon.—Make the dye-bath with 1 lb. Dianil red 4 B, 2 lb. Dianil claret G, 13 oz. Dianil claret B, 5 lb. soda and 20 lb. salt.

Crimson.—Dye with 3 lb. Congo rubine, 5 lb. soda and 20 lb. Glauber's salt.

Dark Maroon.—Use in the dye-bath 1 lb. Benzo purpurine 4 B, 3 lb. Congo Corinth G, 3 lb. soda and 20 lb. Glauber's salt, working at the boil to shade.

Pale Fawn Red.—Use in the dye-bath 1-1/2 oz. Diamine red 5 B, 1-1/2 oz. Diamine catechine G, 3 lb. soda and 10 lb. Glauber's salt.

Rose Red.—Prepare the dye-bath with 3/4 lb. Diamine Bordeaux B, 3 oz. Diamine orange B, 3 lb. soda and 20 lb. salt.

Crimson.—Use in the dye-bath 3/4 lb. Diamine Bordeaux B, 3 oz. Diamine fast yellow B, 3 lb. soda and 20 lb. Glauber's salt.

Salmon.—Dye with 1-1/2 oz. Diamine fast red F, 1-1/2 oz. Diamine fast yellow B, 3 lb. soda and 10 lb. Glauber's salt.

Terra-Gotta Red.—Dye with 1-1/2 lb. Diamine brown M, 3/4 lb. Diamine fast red F, 3 lb. soda and 20 lb. Glauber's salt.

Lilac Red.—Dye with 4 lb. Heliotrope B B, 3 lb. soda and 15 lb. Glauber's salt.

Bright Pink.—Use in the dye-bath 2 oz. Rose azurine G, 1 lb. soda and 10 lb. Glauber's salt. Nearly all the direct reds give good pink tints when used in proportion, varying from 0.1 to 0.25 per cent. of dye-stuff.

Bright Straw.—Dye in a bath made of 1/4 lb. Titan yellow G G, 10 lb. salt, for three-quarters of an hour, then lift, wash and dry.

Yellow.—Prepare a dye-bath with 1 lb. Titan yellow Y, 10 lb. salt. Heat to 180 deg. F., enter the goods, raise to boil, and dye for one hour; lift, wash and dry.

Yellow.—Prepare the dye-bath with 1/4 lb. Diamine fast yellow A, 1 lb. Turkey red oil, 20 lb. Glauber's salt. Dye at the boil for one hour.

Sun Yellow.—Prepare the dye-bath with 2 lb. Sun yellow, 30 lb. common salt. Dye at the boil. The bath is kept for further lots.

Yellow.—Prepare the dye-bath with 1 lb. Direct yellow R, 20 lb. Glauber's salt. Dye at the boil for one hour.

Yellow.—Prepare the dye-bath with 2 lb. Curcuphenine, 20 lb. common salt. Work at the boil for one hour; lift, rinse and dry.

Old Gold.—Make the dye-bath with 5 lb. Diamine yellow N powder, 20 lb. phosphate of soda, 10 lb. soap. Work at the boil for one hour; finish in the usual way. The bath may be kept for other lots of goods.

Dark Yellow.—The bath is made from 2 lb. Toluylene orange G, 10 lb. phosphate of soda, and 2-1/2 lb. soap, working at the boil to shade.

Bright Yellow.—Use 1 lb. Chrysophenine, 2 lb. phosphate of soda and 10 lb. Glauber's salt.

Lemon Yellow.—Use 1 oz. Chrysamine G, 2 lb. phosphate of soda and 10 lb. Glauber's salt.

Yellow.—Dye with 2 lb. Oxyphenine and 20 lb. salt.

Yellow Olive.—Use in the dye-bath 2 oz. Cotton brown N, 4-1/2 oz. Diamine bronze G, 4-1/2 oz. Diamine fast yellow B, 3 lb. soda and 20 lb. salt.

Green Yellow.—Dye with 1/2 lb. Diamine fast yellow B. 2 oz. Diamine bronze G, 3 lb. soda and 10 lb. Glauber's salt.

Gold Yellow.—Use in the dye-bath 3 lb. Columbia yellow, 3 lb. soda and 20 lb. Glauber's salt.

Cream.—Dye with 1/2 oz. Toluylene orange G, 24 grains Brilliant orange G, 1 lb. soda and 10 lb. Glauber's salt.

Primrose.—Dye with 3 oz. Dianil yellow 3 G, 2 lb. soda and 10 lb. salt.

Gold Yellow.—Dye with 2-1/2 lb. Dianil yellow G, 1/2 lb. soda and 15 lb. salt.

Buff Yellow.—Dye with 3-1/2 oz. Dianil yellow 2 R, 1/2 lb. soda and 10 lb. salt.

Orange.—Prepare the dye-bath with 2 lb. Chlorophenine orange R, 20 lb. common salt. Work at the boil for one hour; lift, rinse and dry.

Red Orange.—Make the dye-bath with 3 lb. Mikado orange 4 R and 25 lb. salt. Work at the boil for one hour.

Orange.—Make the dye-bath with 3 lb. Mikado orange G and 25 lb. salt. Work at the boil for one hour.

Pale Orange.—The dye-bath contains 6 oz. Diamine Orange G, 1-1/2 oz. Diamine fast yellow B, 1/4 oz. Diamine scarlet B, 3 lb. soda and 15 lb. Glauber's salt.

Olive Yellow.—Dye with 3/4 lb. Diamine fast yellow B, 1 oz. Oxydiamine black N, 1-1/2 oz. Diamine bronze G, 3 lb. soda and 20 lb. Glauber's salt.

Dark Orange.—Dye with 3 lb. Columbia orange R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Bright Orange.—Use 3 lb. Congo orange R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Pale Orange.—Dye with 3 lb. Dianil orange 2 R, 2 lb. soda and 10 lb. salt at the boil for one hour.

Brilliant Orange.—Dye with 4 lb. Dianil orange G and 20 lb. salt for one hour.

Deep Orange.—Dye with 2 lb. Oxydiamine orange R, 3/4 lb. soda and 20 lb. salt for an hour.

Pale Orange.—Dye with 3/4 lb. Diamine fast yellow B, 1 lb. Diamine orange B, 3 lb. soda and 15 lb. Glauber's salt.

Bright Orange.—Dye with 1-1/2 lb. Benzo orange R, 1-1/2 lb. Chrysamine R, 10 lb. phosphate of soda and 2 lb. soap.

Green.—Prepare the dye-bath with 2 lb. Benzo green G, 10 lb. Glauber's salt. Enter lukewarm, bring slowly to the boil, dye for one hour at the boil.

Russian Green.—Make the dye-bath with 16 oz. Diamine black H W, 4 oz. Diamine fast yellow A, 3 lb. soda, 15 lb. Glauber's salt, working at the boil for one hour, then lift, wash and dry.

Dark Olive.—Prepare a dye-bath with 3-1/2 lb. Benzo olive, 2-1/2 lb. Diamine black B O, 2 lb. Diamine yellow, 20 lb. common salt, 2 lb. soap. The goods are entered into the bath at 160 deg. F., then heat is raised to the boil, and the dyeing continued for one hour, then lift, wash and dry.

Dark Olive.—Dye in a bath of 2 lb. Titan yellow Y, 1 lb. Diamine brown Y, 1-1/2 lb. Diamine blue 3 B, 2 lb. soda. Work for one hour, then lift, wash and dry.

Olive.—Prepare a dye-bath with 15 lb. phosphate of soda, 3 lb. soap, 1-1/2 lb. Diamine yellow N, 4 oz. Diamine blue 3 B, 1-1/2 oz. Diamine brown V. Dye at the boil to shade; lift, wash and dry.

Green Olive.—Prepare the dye-bath with 1 lb. Diamine black R O, 1 lb. Chrysamine, 1/4 lb. Benzo brown, 5 lb. soda, 5 lb. salt, 2 lb. soap. The goods are entered at about 180 deg. F. and worked for a short time, then the temperature is raised to the boil, and the goods are worked for one hour, lifted, washed and dried.

Reseda.—Prepare a bath with 10 lb. Glauber's salt, 2 lb. soap, 1/2 lb. Diamine black R O, 2 lb. Diamine yellow N. Enter at 120 deg. F., heat to boil and dye for one hour at that temperature; lift, wash and dry.

Sage Green.—Prepare a dye-bath with 10 lb. Glauber's salt, 1/2 lb. Diamine black R O, 2 lb. Diamine yellow N. Enter at about 150 deg. F. and then raise to boil and dye boiling for one hour, wash and dry.

Drab.—Prepare the dye-bath with 10 lb. Cross dye drab, 5 lb. soda crystals. Enter at the boil and work at this temperature for half an hour. Whilst dyeing add gradually 75 lb. salt. Rinse well and dry.

Olive.—Prepare the dye-bath with 2 lb. Dianil olive, 5 lb. phosphate of soda, 5 lb. common salt. Dye at the boil for one hour.

Olive.—The dyeing is done in a bath containing 4 oz. Diamine black H W, 1-3/4 lb. Diamine bronze G, 5 lb. soda, 15 lb. Glauber's salt. Work at the boil for one hour.

Grass Green.—Make the dye-bath with 2 lb. Chrysamine G, 1-1/2 oz. Benzo azurine G, 3 lb. soap and 10 lb. borax, working at the boil for one hour.

Green.—Make the dye-bath with 2 lb. Titan yellow Y, 1 lb. Titan blue 3 B and 20 lb. salt.

Bright Grass Green.—Dye for an hour at the boil with 1 lb. Sulphon azurine D, 2 lb. Thiazole yellow and 20 lb. Glauber's salt.

Green.—Use in the dye-bath 3 lb. Diamine green B, 3 lb. soda and 20 lb. Glauber's salt, working at the boil to shade.

Dark Green.—Dye with 3 lb. Diamine dark green N, 3 lb. soda and 20 lb. Glauber's salt.

Green.—Use in the bath 3 lb. Benzo green B B, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Dark Sea Green.—Dye with 5 oz. Diamine black H W, 3 oz. Diamine catechine G, 3 oz. Diamine fast yellow B, 3 lb. soda and 10 lb. Glauber's salt.

Pale Green.—Use in the dye-bath 3 lb. Diamine fast yellow B, 2 oz. Diamine black H W, 3 lb. soda and 10 lb. Glauber's salt.

Bright Pea Green.—Use in the dye-bath 1 oz. Thioflavine S, 1/4 oz. Diamine sky blue F F and 20 lb. Glauber's salt.

Dark Green.—Use 1-3/4 lb. Diamine green G, 3/4 lb. Oxydiamine yellow G G, 3 lb. soda and 20 lb. Glauber's salt, working at the boil for one hour.

Deep Green.—Use 1-3/4 lb. Diamine green G, 3/4 lb. Diamine black B H, 1/2 lb. Oxydiamine yellow G G, 3 lb. soda, and 20 lb. Glauber's salt.

Sea Green.—Use 2 oz. Dianil yellow R, 2-1/2 oz. Dianil blue B, 1-3/4 oz. Dianil dark blue R, 1 lb. soda, and 20 lb. salt, working at the boil.

Leaf Green.—Dye with 1-1/2 lb. Dianil yellow 3 G, 1 lb. Dianil blue B, 11 oz. Dianil blue 2 R, 3 lb. soda, and 20 lb. salt at the boil for one hour.

Deep Green.—Dye with 2-1/2 lb. Dianil yellow 3 G, 2-1/2 lb. Dianil blue 2 R, 6 oz. Dianil dark blue R, 3 lb. soda, and 20 lb. salt at the boil for one hour.

Greens are largely produced by mixing yellows and blues together as will be seen from the recipes given above; the particular shade of green which is got from a combination of blue and green depends upon the quality of the dye-stuffs used: thus, to produce bright greens of a pure tone, it is essential that the yellow used shall have a greenish tone like Thioflavine S, Thiazole yellow, or Dianil yellow 3 G, while the blue must also have a greenish tone like Diamine sky blue, Benzo blue 3 B, etc. By using yellows like Diamine fast yellow R, and dark blues like Benzo azurine 3 R, Diamine blue R W, Dianil dark blue R, the green which is got is darker and duller in tone. The addition of such a dye as Diamine black B H throws the shade more on to an olive, while a brown dye-stuff, like Diamine brown M, or an orange dye, like Titan orange N, throws the green on to a sage tone. Examples of these effects will be found among the recipes given above.

It may be added here that by using smaller quantities, but in the same proportions as given in the above recipes, a great range of tints and shades of green can be dyed from very pale to very deep.

Bright Blue.—Prepare a dye-bath with 1/2 lb. Congo blue 2 B, 5 lb. salt, 5 lb. phosphate of soda, 2 lb. soap. Work at the boil for one hour, then rinse and dry.

Dark Navy.—Prepare a dye-bath with 1 lb. Diamine black R O, 2 lb. Diamine blue 3 R, 8 lb. Glauber's salt, 2 lb. soap. Enter the cotton at 180 deg. F., and boil for one hour.

Pale Blue.—Prepare a dye-bath with 10 lb. salt, 3 lb. soda, 3 oz. diamine blue 3 R. Work for one hour at the boil, then lift, wash and dry.

Sky Blue.—Prepare a dye-bath with 2 lb. Titan como G, 20 lb. common salt, 2 oz. acetic acid. Work at the boil for half an hour, then lift, wash and dry.

Bright Blue.—Prepare the dye-bath with 1-1/2 lb. Chicago blue 6 B, 20 lb. Glauber's salt, 3 lb. soap. Work at the boil for one hour, then lift, wash and dry.

Pale Sky Blue.—Make the dye-bath with 1 oz. Chicago blue 6 B, 10 lb. Glauber's salt, 2 lb. soap. Work at the boil for one hour, then lift, wash and dry.

Sky Blue.—Prepare the dye-bath with 1 lb. Diamine sky blue F F, 1 lb. Turkey-red oil, 20 lb. Glauber's salt. Dye at the boil for one hour.

Dark Blue.—Prepare the dye-bath with 2-1/2 lb. Diamineral blue R, 2-1/2 lb. Diamine deep black Cr, 1 lb. Turkey-red oil, 40 lb. Glauber's salt. Dye at the boil for one hour.

Dark Blue.—Prepare the dye-bath with 3 lb. Triamine black B, 15 lb. Glauber's salt, in 50 gallons of water. Enter at 150 deg. F., and boil for one hour. Allow the goods to remain until the water is cold, when the dye-bath will be completely exhausted.

Blue.—Prepare the dye-bath with 2 lb. Diamine steel blue L, 2 lb. soda, 15 lb. Glauber's salt. Dye at the boil for one hour.

Blue.—Prepare the dye-bath with 4 lb. Diamine blue B G, 2 lb. soda, 20 lb. Glauber's salt. Dye at the boil for one hour. In shade this is very similar to that got with Diamine brilliant blue G, which however should be used for light shades on account of its brightness. For deep shades Diamine blue B G, is preferable, because of its greater tinctorial power.

Light Indigo Blue.—Prepare the dye-bath with 1 lb. Paramine indigo blue, 2 lb. soda, 20 lb. Glauber's salt. Enter at about 150 deg. F., and dye at the boil for one hour.

Navy Blue.—Prepare the dye-bath with 4 lb. Paramine navy blue R, 2 lb. soda, 20 lb. Glauber's salt. Enter at about 150 deg. F., and dye at the boil for one hour.

Blue.—Prepare the dye-bath with 1 lb. Paramine navy blue R, 2 lb. soda, 20 lb. Glauber's salt. Enter at about 150 deg. F., and dye at the boil for one hour.

Navy Blue.—Prepare the dye-bath with 4 lb. Benzo chrome black blue B, 15 lb. Glauber's salt, 3 lb. soda. Work at the boil for one hour; lift, rinse and dry.

Grey Blue.—Prepare the dye-bath with 2 lb. Paramine blue black S, 2 lb. soda, 20 lb. Glauber's salt. Enter at 150 deg. F., and dye for one hour at boil.

Blue.—Prepare the dye-bath with 1 lb. Paramine blue B, 2 lb. soda, 20 lb. Glauber's salt. Enter at about 150 deg. F., and dye at the boil for one hour.

Slate Blue.—Prepare the dye-bath with 1/4 lb. Diamine black B H, 3/4 oz. Diamine fast yellow B, 2 lb. soda, and 10 lb. Glauber's salt. Dye at the boil to shade.

Deep Blue.—Use 3-1/4 lb. Diamine blue B X, 1/2 lb. Oxydiamine black N, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Blue.—Dye at the boil for one hour with 1-1/2 lb. Diamine sky blue, 2 oz. Diamine green B, 2 lb. soda and 10 lb. Glauber's salt.

Navy.—Dye with 1 lb. Dianil dark blue R, 8 oz. Dianil black C R, 5 lb. soda and 20 lb. salt at the boil for one hour.

Dark Navy.—Use 2 lb. Dianil blue B, 2 lb. Dianil dark blue R, 3/4 lb. Dianil black C R, 2 lb. soda and 25 lb. salt, working at the boil for one hour.

Deep Blue.—Dye with 3-1/2 lb. Diamine blue black E, 5 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Deep Blue.—Dye with 3 lb. Zambesi black B R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Dark Navy.—Use 3 lb. Dianil dark blue R, 3 lb. caustic soda 70 deg. Tw., and 25 lb. salt, working at the boil for one hour.

Violet Blue.—Dye with 3 lb. Dianil dark blue 3 R and 25 lb. salt at the boil for one hour.

Bright Blue.—Use 1 lb. Dianil blue B, and 20 lb. salt, working at the boil for one hour.

Full Blue.—Dye with 3 lb. Brilliant azurine 5 G, 5 lb. common salt, 5 lb. phosphate of soda and 2 lb. soap at the boil for one hour.

Dark Blue.—Dye with 3 lb. Erie blue B X, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Pale Blue.—Dye with 1 lb. Chicago blue 6 B, 3 lb. soda and 20 lb. salt at the boil for one hour.

Deep Blue.—Dye with 1-1/2 lb. Oxydiamine black A, 2 lb. Diamine deep blue R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Blue.—Dye with 6 oz. Diamine blue 3 B, 1-1/2 oz. Diamine sky blue F F, 3 lb. soda and 10 lb. Glauber's salt.

Navy.—Dye with 4 lb. Diamine new blue R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Dark Navy.—Dye with 1-3/4 lb. Diamineral blue R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Sky Blue.—Prepare the dye-bath with 6 oz. Diamine sky blue F F, 3 lb. soda and 10 lb. Glauber's salt, working at the boil for one hour.

Dark Blue.—Use in the dye-bath 3 lb. Diamine blue R W, 2 lb. soda and 20 lb. Glauber's salt, working at the boil for one hour.

Dark Blue.—Prepare the dye-bath with 3 lb. Triamine black B T, and 15 lb. Glauber's salt; work at the boil to shade.

Blue.—Use 2 lb. Direct indigo blue and 15 lb. Glauber's salt; work at the boil.

Bright Blue.—Use in the dye-bath 3 lb. Titan como S N, 2 lb. acetic acid and 20 lb. salt, working at the boil for one hour.

Turquoise Blue.—Dye with 1 lb. Diamine sky blue, 1 oz. Diamine fast yellow B, 2 lb. soda and 10 lb. Glauber's salt, working at the boil to shade.

Dark Navy.—Use 4 lb. Titan navy R, and 20 lb. salt at the boil for one hour.

Green Blue.—Dye with 1 lb. Dianil blue G, 2-1/2 oz. Dianil yellow G, 1 lb. soda and 20 lb. salt at the boil for one hour.

Many more formulae could have been given, but the above will perhaps suffice; they include all the best of the direct blues. Paler tints of blue may be got by using from 1 to 2 per cent. of any of these blues and also of the many direct blacks now on the market. The direct blues as a rule have a good degree of fastness to light.

Lilac.—Prepare a dye-bath with 1/4 lb. Hessian brown 2 M, 1 oz. Azo mauve A M, 1 lb. soap, 2 lb. soda, 10 lb. salt. Work at the boil for one hour, then lift, wash and dry.

Plum.—Dye with 3 lb. Oxydiamine violet G, 3 lb. soda and 20 lb. salt.

Dark Plum.—Use in the dye-bath 3 lb. Oxydiamine violet B, 3 lb. soda and 20 lb. Glauber's salt, working at the boil.

Violet.—Make the dye-bath with 3/4 lb. Oxydiamine violet B, 1 lb. soda and 10 lb. Glauber's salt, and dye at the boil to shade.

Violet.—Dye with 12 oz. Dianil blue 4 R, 2 oz. Dianil blue B and 10 lb. salt at the boil.

Lilac.—Dye with 1-1/2 oz. Diamine rose G D, 3/4 oz. Diamine sky blue F F, 1 lb. soda and 10 lb. Glauber's salt at the boil to shade.

Red Violet.—Make the dye-bath with 1/2 lb. Diamine violet N, 1/2 oz. Diamine brilliant blue G, 1 lb. soda and 10 lb. Glauber's salt, working at the boil.

Red Violet.—Dye with 1 lb. Diamine violet N, 1 lb. soda and 10 lb. Glauber's salt.

Bright Red Lilac.—Dye with 1-3/4 lb. Erika B N, 4 oz. Chicago blue 4 R, 3 lb. soda and 20 lb. Glauber's salt at the boil.

Grey Lilac.—Dye with 12 oz. Neutral grey G, 3 oz. erika B N, 1 lb. soda and 10 lb. Glauber's salt at the boil for one hour.

Pale Lilac.—Dye with 2-1/2 oz. Dianil claret B, 2-1/2 oz. Dianil blue 4 R, and 10 lb. salt.

Light Plum.—Dye with 10 oz. Dianil claret B, 10 oz. Dianil blue and 20 lb. salt.

Dull Lilac.—Dye with 1/2 lb. Diamine brown V, 1 lb. soda and 10 lb. Glauber's salt.

Heliotrope.—Dye with 4 oz. Heliotrope 2 B, 1 lb. soda and 10 lb. Glauber's salt.

Plum.—Dye with 3 lb. Congo Corinth B, 3 lb. soda and 10 lb. Glauber's salt.

Dull Violet.—Use in the dye-bath 1-1/2 lb. Chicago blue 4 R, 14 oz. Erika B N, 3 lb. soda and 20 lb. Glauber's salt, working at the boil for one hour.

Red Lilac.—Dye with 6 oz. Oxydiamine violet G, 2 oz. Oxydiamine violet B, 1 lb. soda and 10 lb. Glauber's salt at the boil for one hour.

Violet.—Dye with 3 oz. Diamine violet N, 2 oz. diamine blue 3 R, 1 lb. soda and 10 lb. Glauber's salt.

Fawn Drab.—Prepare a dye-bath with 1 lb. Cachou de laval, 1/4 oz. Benzo purpurine B. Enter the cotton into this bath in the cold and heat to the boil, taking about one hour for the operation, then add 4 lb. common salt and boil for three-quarters of an hour longer; lift, wash and dry.

Pale Olive Brown.—The dye-bath is made with 1 lb. Diamine bronze G, 1 oz. Cotton brown N, 3 oz. Diamine gold, 5 lb. soda, 15 lb. Glauber's salt. Work at the boil for one hour, then lift, wash and dry.

Red Brown.—Prepare a dye-bath with 1-3/4 lb. Cotton yellow, 4 lb. Hessian brown 2 B N, 2 lb. Diamine black R O, 1 lb. soda, 2 lb. salt. Enter the goods at 180 deg. F., then raise to the boil and work to the shade; lift, wash and dry.

Brown Drab.—Prepare a dye-bath with 1/4 lb. Cotton brown N, 3/4 oz. Diamine yellow N, 3/4 oz. Diamine black B O, 15 lb. phosphate of soda, 3 lb. soap. Work at the boil for one hour.

Gold Brown.—Prepare the dye-bath with 16-1/4 oz. Toluylene orange G, 9-1/2 oz. Toluylene orange R, 4-3/4 oz. azo mauve, 2-1/2 lb. soap, 5 lb. soda. Dye at the boil for one hour.

Chestnut Brown.—Prepare a dye-bath with 10 lb. common salt, 2 lb. Benzo brown G, 1/2 lb. Benzo azurine G, 1/2 lb. Chrysophenine. Enter the goods at 150 deg. F., raise to the boil and dye boiling for one hour.

Purple Brown.—Prepare a dye-bath with 10 lb. common salt, 2 lb. Benzo brown N B, 1 lb. Azo violet. Enter the cotton at 150 deg. F., raise to the boil and dye boiling for an hour; lift, wash and dry.

Brown.—Prepare a dye-bath with 5 lb. soda, 10 lb. Glauber's salt, 12 oz. Chrysamine, 1 oz. Benzo purpurine, 6-1/4 oz. Benzo azurine. Dye at the boil for one hour, rinse and dry. The brown thus got is fast to washing.

Dark Chestnut Brown.—Prepare a dye-bath with 10 lb. salt, 3 lb. Benzo brown N B X, raise to 150 deg. F., enter goods, heat to boil, and work for one hour; lift, rinse and dry.

Dark Brown.—Prepare a dye-bath with 20 oz. Glauber's salt per gallon of water used, 2-1/2 lb. soap, 1-1/2 lb. Diamine black R O, 2 lb. Cotton brown N. Enter the yarn at 180 deg. F., give three turns, raise temperature to boil, and work to shade; lift, rinse and wash.

Gold Brown.—Prepare the dye-bath with 4 lb. Titan gold, 50 lb. salt. Work at the boil for thirty minutes, then lift, wash and dry. The dye-bath is not exhausted, only about 3 lb. of the colour being taken up by the cotton. It may, therefore, be kept for further lots, adding 3 lb. more colour and about 20 lb. more salt for each batch of cotton, or if it is not desired to keep the bath, add less colour to start with, and towards the end of the operation add more salt.

Brown.—Prepare the dye-bath with 4 lb. Paramine brown G, 20 lb. Glauber's salt, 2 lb. soda. Dye at the boil for one hour.

Light Brown.—Prepare the dye-bath with 3 lb. Diamine catechine G, 3 lb. soda, 15 lb. Glauber's salt. Dye at the boil for one hour.

Dark Brown.—Prepare the dye-bath with 5 lb. Diamine catechine B, 3 lb. soda, 15 lb. Glauber's salt. Dye at the boil for one hour.

Dark Drab.—Prepare the dye-bath with 1 lb. Titan brown Y, 3 oz. Columbia green, 32-3/4 oz. Diamine bronze, 17 lb. Glauber's salt. Work at the boil for one hour, then lift, wash and dry.

Pale Brown.—The dye-bath is made with 2 lb. Mikado orange 4 R, 3 oz. Benzo fast grey, 30 lb. Glauber's salt. Work at the boil for one hour, then lift, ash and dry.

Gold Brown.—Make a dye-bath with 1 lb. Titan gold, 50 lb. common salt. Enter at the boil, work for an hour, then lift, wash and dry. Keep the bath for another lot of goods; it will only require the addition of about 14 oz. of colour and 10 lb. salt.

Buff Brown.—Make the dye-bath with 3/4 lb. Titan gold, 1/4 lb. Titan brown R, 5 oz. Titan blue 3 B, 40 lb. common salt. Work at the boil to shade, then lift, wash and dry.

Deep Chestnut Brown.—Make the dye-bath with 3 lb. Titan brown R, 1-1/2 lb. Titan blue R, 25 lb. common salt. Work at the boil for an hour, then lift, wash and dry.

Light Seal Brown.—Make the dye-bath with 10 lb. salt, 2 lb. soda, 14 oz. Oxyphenine, 3/4 lb. Atlas red R, 6 oz. Diamine blue B X. Work at the boil to shade, then lift, wash and dry.

Orange Brown.—Make a dye-bath with 10 lb. salt, 2 lb soda, 14 oz. Oxyphenine, 1 lb. Atlas red R, 1 oz. Diamine blue B X. Work at the boil to shade, then lift, wash and dry.

Pale Nut Brown.—Use in the dye-bath 4-1/2 oz. Diamine catechine G, 1 oz. Diamine brown M, 1 oz. Diamine catechine B, 2 lb. soda and 10 lb. Glauber's salt, working at the boil for one hour.

Walnut Brown.—Dye with 1 lb. Diamine brown M, 3 oz. Diamine orange G, 2 oz. Diamine black H W, 2 lb. soda and 10 lb. Glauber's salt at the boil for one hour.

Black Brown.—Use in the dye-bath 3 lb. Diamine brown M, 3/4 lb. Diamine blue black R, 3 lb. soda and 20 lb. Glauber's salt, working at the boil.

Reddish Brown.—Dye with 2 lb. Dianil brown R, 5 lb. salt and 5 lb. phosphate of soda at the boil for one hour.

Chocolate Brown.—Dye with 2 lb. Dianil brown T, 5 lb. phosphate of soda and 5 lb. salt at the boil for one hour.

Dark Brown.—Dye with 2 lb. Dianil dark brown, 5 lb. salt and 5 lb. phosphate of soda at the boil for one hour.

Light Brown.—Prepare the dye-bath with 5 lb. Diamine catechine G, 3 lb. soda and 15 lb. Glauber's salt.

Brown.—Dye with 2-1/4 lb. Cotton brown N, 4 oz. Diamine black H W, 2 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

Dark Walnut Brown.—Make the dye-bath with 3-1/4 lb. Diamine brown M, 6 oz. Diamine catechine B, 6 oz. Diamine red 5 B, 2 lb. soda and 20 lb. Glauber's salt; work at the boil.

Dark Chestnut Brown.—Dye with 2-1/2 lb. Dianil brown R, 1 lb. soda and 20 lb. salt at the boil.

Dark Brown.—Dye with 2 lb. Dianil brown 3 G O, 2 lb. Dianil brown B D, 1 lb. Dianil red 4 B, 3 lb. soda and 25 lb. salt at the boil for one hour.

Brown.—Prepare the dye-bath with 5 lb. Mikado brown M and 25 lb. salt; work the cotton in this at the boil for one hour.

Nut Brown.—Use in the dye-bath 2-1/2 lb. Benzo brown G and 15 lb. salt, working at the boil.

Dark Brown.—Use in the dye-bath 3 lb. Benzo brown N B and 15 lb. Glauber's salt, working at the boil.

Dark Brown.—Make the dye-bath with 4 lb. Diphenyl brown B N, 10 lb. Glauber's salt and 4 lb. soap, working at the boil to shade.

Black Brown.—Use in the dye-bath 2-1/2 lb. Dianil brown 3 G O, 1-1/2 lb. Dianil brown G, 3/4 lb. Dianil dark blue R, 3 lb. soda and 25 lb. salt.

Dark Brown.—Dye with 1-1/2 lb. Zambesi black D, 1-1/4 lb. Brilliant orange G, 3 lb. soda and 20 lb. Glauber's salt at the boil to shade.

Gold Brown.—Dye with 2 lb. Curcumine S, 1 lb. Columbia orange R, 5 oz. Columbia black F B, 3 lb. soda and 15 lb. Glauber's salt at the boil.

Dark Chestnut.—Dye at the boil with 2 lb. Columbia Orange R, 8 oz. Columbia black F B, 2 lb. soda and 10 lb. Glauber's salt.

Sage Brown.—Dye with 1 lb. Zambesi black D, 1 lb. Curcumine S, 3/4 lb. Diamine orange G D, 3 lb. soda and 30 lb. Glauber's salt at the boil.

Deep Brown.—Dye 3-1/2 lb. Diamine brown M, 3/4 lb. Oxydiamine orange G, 3/4 lb. Diamine black H W, 3 lb. soda and 20 lb. Glauber's salt at the boil.

Chestnut.—Dye with 2-1/2 lb. Diamine brown G, 3/4 lb. Oxydiamine orange R, 3 lb. soda and 20 lb. Glauber's salt.

Pale Walnut Brown.—Dye with 3-1/2 lb. Diamine brown M, 3/4 lb. Oxydiamine orange G, 1-1/2 oz. Diamine black B H, 3 lb. soda and 20 lb. Glauber's salt.

Various other browns may be obtained by combining the various direct browns together or with other direct dyes. The use of a yellow or orange will brighten them; that of a red will redden the shade; the addition of a dark blue or a black will darken the shade considerably. It may be useful to remember that a combination of red, orange and blue or black produces a brown, and by using various proportions a great range of shades can be dyed.

Black.—Prepare a dye-bath with 6 lb. Diamine black R O, 2 oz. Thioflavine S, 2 lb. soap, 10 lb. salt. Enter the cotton at the boil and dye for one hour; lift, wash and dry.

Black.—Prepare the dye-bath with 5 lb. Direct deep black E extra, and 1/2 to 1-1/2 oz. common salt per gallon of water. Dye at the boil for one hour.

Deep Black.—Prepare the dye-bath with 5-1/2 lb. Diamine deep black R B, 2 lb. soda, 20 lb. Glauber's salt. Dye at the boil for one hour; lift, wash and dry.

Black.—Prepare the dye-bath with 5 lb. Direct triamine black G X, 15 lb. Glauber's salt. Dye for one hour at the boil; lift, rinse and dry. In working for from two to three hours the dye-bath will exhaust completely.

Black.—Prepare the dye-bath with 5 lb. Oxydiamine black A, 20 lb. Glauber's salt, 2 lb. soda. Dye at the boil for one hour.

Black.—Prepare the dye-bath with 6 lb. Pluto black B. Dye at the boil for one hour with the addition of 3/4 to 1-1/4 oz. Glauber's salt, 1/2 to 3/4 oz. soda ash per gallon of liquor. To develop the shade it is necessary to dye in a boiling liquor.

Black.—Use 2-1/2 lb. Diamine jet black Cr, 2-1/2 lb. Diamine jet black R B, 2 lb. soda, and 20 lb. Glauber's salt, working at the boil for one hour.

Black.—Use 6 lb. Oxydiamine black N R, 2 lb. soda and 20 lb. Glauber's salt, working at the boil for one hour.

Black.—Use 6 lb. Columbia Black F B B, 3 lb. soda and 20 lb. Glauber's salt, working at the boil to shade.

Besides the blacks given in the above recipes, there are other brands which are used in the same way, and vary slightly in the shade of black they give.

All the direct blacks require working in strong baths to give anything like black shades; they all have, more or less, a bluish tone, which can be changed to a jetter shade by the addition of a yellow or green dye in small proportions, which has been done in one of the recipes given above.

By coupling, chroming or developing, the direct blacks can be made to give full, deep and fast blacks, and examples of their use in this manner will be found in following sections.

By using all the direct blacks in proportions varying from 1/4 to 1 per cent. of dye-stuff to the weight of the cotton they give greys of various tints and depths; a few examples of such greys will now be given.

Blue Grey.—Prepare the dye-bath with 1/2 lb. Oxydiamine black A, 1 lb. soda, 10 lb. Glauber's salt. Dye at the boil for one hour.

Bright Grey.—Prepare a dye-bath with 4-1/2 oz. Azo mauve A M, 1-1/2 oz. Direct yellow G, 3 lb. soda, 15 lb. common salt.

Silver Grey.—Prepare the dye-bath with 1/2 oz. Neutral grey G, 10 lb. sulphate of soda. Work at the boil to shade, then lift, wash and dry.

Slate.—Dye in a bath with 1/2 lb. Diamine black B H, 3 oz. Diamine bronze G, 15 lb. Glauber's salt at the boil for three-quarters of an hour.

Bronze Grey.—Prepare a dye-bath with 1/2 lb. Diamine bronze G, 15 lb. Glauber's salt, 3 lb. soap. Enter at about 160 deg. F., raise to boil and work for one hour; lift, wash and dry.

Dark Slate.—Prepare a dye-bath with 10 lb. Glauber's salt, 1-1/2 lb. soap, 1 lb. Diamine black R O, 2 lb. Cotton brown N. Heat to about 150 deg. F. Enter the goods, work for a short time, then raise to the boil and work for one hour; lift, wash and dry.

Green Grey.—Prepare a dye-bath with 10 lb. Glauber's salt, 1 lb. Diamine black R O, 3/4 oz. Thioflavine S. Enter at from 150 deg. Tw. to 180 deg. F., raise to boil and dye for one hour; wash and dry.

Light Slate.—Prepare a dye-bath containing 2-1/4 lb. soap, 15 lb. Glauber's salt, 6 oz. Diamine black R O, 1/2 oz. thioflavine S. Enter cotton at 140 deg. F., work a little, then heat to boil and dye to shade; lift, wash and dry.

Grey.—Prepare the dye-bath with 1/2 lb. Diamine grey G, 1/2 oz. Diamine scarlet B, 1 lb. soda, 1 lb. soap, 5 lb. Glauber's salt. Dye for one hour at the boil.

Light Grey.—Prepare the dye-bath with 1 lb. Diamine grey G, 1 lb. soda, 1 lb. soap, 5 lb. Glauber's salt. Dye for one hour at the boil; lift, rinse and dry.

It may be convenient here to deal with the question of the fastness of the direct dyes to such influences as light, air, acids, alkalies, washing and soaping, that have a very material influence on the use of these dyes in dyeing various fabrics. This matter can only be dealt with here in very general terms, for space is limited and the dyes are too numerous for detailed mention. They vary very greatly in degrees of fastness, some are absolutely fast to all influences; the blacks are among the fastest, generally these resist washing and soaping, stand acids well and are fast to alkalies, light however affects them more or less, though they cannot be reckoned fugitive colours. The few direct greens known are good colours; they stand washing, soaping and light well, but they are affected by acids and alkalies. The blues vary very much, generally they stand soaping and have a fair degree of fastness to light, acids have but little action, alkalies tend to redden the shade, while heat also affects them. The direct browns are very variable; they are in general not fast to light; they stand washing and soaping and resist alkalies, but are altered by acids slightly. The yellows rank among the fastest of colours to light and washing and soaping; acids have but little effect; they are reddened by alkalies. Among the reds there is great variation in properties, generally they are not fast to light, standing washing and soaping well and resisting weak alkalies; some of them, such as the Benzo purpurines and Congo reds are very sensitive to acids, being turned blue with very weak acids, but on washing or soaping the original colour comes back; others, like the Titan reds, Diamine reds and Delta purpurines are not so sensitive, but these are affected by moderately strong acids; there are one or two reds like Benzo fast scarlet 4 B S and Purpuramine D H, which are fast to acids. The depth of shade which is dyed has some considerable influence on the degree of fastness, the deeper shades of a colour are always faster than the paler shades, particularly as regards light, a difference of 1/2 per cent, of dye-stuff has been known to make a very appreciable degree of difference as regards the fastness of a colour to light.

In dyeing cotton with all the direct dyes, it is found that the whole of the dye-stuff is not removed from the dye-bath, how much is taken up by the cotton, and the depth of the shade which is dyed upon the cotton chiefly depends upon three factors:—

(1) Volume of water used. (2) Quantity of saline salts used. (3) Degree of affinity of the dye-stuff for the fibre.

There may also be some minor factors such as temperature at which the dyeing is carried on, the character and condition of the fabrics being dyed, etc.

The volume of water used in making the dye-bath has a very great influence upon the amount of dye taken up by the cotton, the greater the volume of water the less dye is absorbed and the paler the colour which is produced upon the fibre. It is therefore important to use as little water as possible in making up the dye-bath, indeed, for anything like good results to be obtained with some dyes, especially those of the sulphur series like Vidal black, Immedial blacks, Katigen browns, Cross-dye blacks, Amidazol blacks, etc., it is necessary to employ what is called a short bath, that is making it as strong as possible. The proportion of water with such dyes should not exceed fifteen times the weight of the cotton being dyed, that is, for every pound of cotton, 1-1/2 gallons of water can be allowed. This will suit the dyeing of yarns and loose fabrics like knitted stockings and hosiery goods very well. In the case of dyeing piece goods on a jigger or continuous dyeing machines even stronger liquors can be used with advantage. With some of the older, direct dyes like Congo red, Benzo azurine, Diamine scarlets, the proportion of water may be increased to twenty times the weight of the cotton. In any case the quantity of water used should not exceed twenty-five times the weight of the cotton.

The second factor, the quantity of saline salts, like Glauber's salt, soda, borax, etc., added in the dyeing, is not without influence, generally the more that is added the more dye there is left in the bath, but here again much depends upon the salt and the colouring matters used. Some salts, more particularly Glauber's salt and common salt, tend to throw some dye-stuffs out of the bath, and so the more there is used of them the deeper the shade produced on the fabric. It is quite impossible, having regard to the scope of this book, to deal with this question in detail. The dyer should ascertain for himself the best salts and the best proportions of these to use with the particular dyes he is using. The recipes given above will give him some ideas on this point.

The third factor, the degree of affinity of the dye for the cotton fibre, has some influence on the depth of shade which can be dyed from any given strength of the dye-bath. There is a very considerable difference among the direct dyes in this respect. There are some which have a fair degree of affinity, while there are others which have but little affinity, and while in the former case there is little dye left in the bath, in the latter case there is a good deal. When dyeing plain shades with single dye-stuffs this is not of much moment, because if the bath be kept for further use, as will be spoken of presently, the bath may be brought up to its original strength by adding a proportionate amount of dye-stuff, but when compound shades are being dyed, using two or more dyes, then this feature has some influence, for they will not be absorbed by the fibre in the same proportion as they were put in the bath, and so when making up the dye-bath for the second lot, and adding the same proportion of dyes, the shade which is produced will not be quite the same, for the first lot of cotton in taking up the dyes in varying quantities has altered their relative proportions, and so the bath for the second lot of cotton will actually contain more of one dye than did the first bath, and the influence of this excess of the one constituent will show itself in the shade ultimately dyed. The more lots of cotton there are dyed in the bath the greater will this influence be. The dyer must by practical experience find out for himself in what direction this feature of the direct dyes exerts its influence on the particular dyes he is working with and make due allowance.

It is found in practice that from one-fourth to one-half of the original weight of dye-stuff is left in the bath, and in order to be as economical as possible a custom has arisen of keeping the bath and using it again for dyeing further lots of cotton. In thus making a continuous use of dye-baths it is important in preparing the baths for the next lot of cotton to add first the requisite quantities of dye-stuffs, how much will depend upon the factors and conditions already detailed, but from one-half to three-fourths of the original quantities are added. Practical experience alone is the guide to be followed.

Having added the dye-stuff, then sufficient water must be added to bring up the volume of the bath to the proper amount, for it will have lost some. The loss of water arises from two sources: first there is the evaporation, which always occurs when dye-baths are heated up, and, second, there is the mechanical loss due to its absorption by the material which is being dyed. When a piece of cotton or other textile fabric is immersed in a dye liquor it absorbs mechanically some of it, and this amount may be roughly put down as about its own weight; thus 100 lb. weight of cotton will take up 10 gallons of liquor and carry that quantity out of the bath. To some extent this may be minimised by a previous wetting out of the cotton, which will then have in it as much liquor as it will take up, and so practically no more will be taken up from the dye-bath. Any loss of volume which may thus occur can be remedied by the addition of water.

The dye-baths containing in solution, in addition to the dye-stuff, salt, or Glauber's salt, or any other added substance, the cotton in taking up the dye liquor will of course take up some of these in proportion to the volume of liquor absorbed. The amount may range from 4 oz. to 1 lb. per gallon of liquor, and if 100 lb. cotton is being dyed and takes up from 10 to 15 gallons of liquor, it is obvious that it must absorb from 3 to 10 lb. of saline matter, and as the salinity of the dye liquor is of some importance in dyeing direct colours, in making up the bath for the next lot of cotton this must be allowed for and suitable additions made. In order to do this properly it is a good plan to rely upon the Twaddell.

The dyer should take the Twaddell of his bath before use and always make up his baths to that strength. This will be found to range from 3 deg. to 12 deg. Tw.

Thus, for instance, a dye-bath made from 120 gallons of water with 20 lb. to 25 lb. common salt or Glauber's salt with the dye-stuffs will stand at 4 deg. Tw., one made with 50 lb. common salt or Glauber's salt at 8 deg. Tw., while one which is made with 80 lb. to 100 lb. salt will stand at 12 deg. to 13 deg. Tw. If the dyer always maintains his liquors at one uniform degree Twaddell he can invariably depend upon getting uniform shades from his dye-baths. This uniform strength is attained by adding more salt or more water as the case may require.

Of course the continuous working of dye-baths cannot go on for ever; sooner or later the baths become thick and dirty, and then they must be thrown away and a new bath started.

(2) DIRECT DYEING FOLLOWED BY FIXATION WITH METALLIC SALTS.

It is an acknowledged principle in dyeing that to produce colours fast to washing, soaping and rubbing, there must be produced on the fibre an insoluble coloured substance. Now as the direct dyes do not essentially produce such insoluble bodies when dyed on the cotton, the colours they form are not always fast to washing and soaping. It has been ascertained, however, that some of the direct dyes, e.g., Benzo azurine, Chicago blue, Catechu browns, Diamine blues, Diamine browns, etc., are capable of uniting with metallic bodies to form insoluble colour lakes, and this combination can take place on the fibre. Fast shades may be dyed with the dye-stuffs named above, and with others of this group, by first dyeing them in the usual way, then passing through a boiling bath containing bichromate of potash or copper sulphate, either together or separately. The two fixing agents here named have been found to be the best, although others, as, for instance, zinc sulphate, chromium fluoride and iron sulphate have been tried. With some dyes there is little or no alteration in shade, but in others there is some change, thus the blues as a rule tend to become greener in tone, and browns also tend to acquire a greener tone and deeper shade. The treated shades thus obtained are notable for considerable fastness to washing, soaping and light. It is to be noted that bichromate of potash exercises both a fixing and an oxidising action on dye-stuffs, hence it is needful to use it with some degree of caution and not in too great an amount, otherwise with some dyes there is a risk of over-oxidation, and in consequence poor shades will be developed. The following recipes will serve to show what dyes may thus be used, and the colours that can be obtained with them.

Dark Red.—Use in the dye-bath 3 lb. Diamine fast red F, 3 lb. soda and 20 lb. Glauber's salt, work at the boil for one hour, then lift, rinse and pass into a boiling bath containing 3 lb. fluoride of chromium for ten to fifteen minutes, then lift, rinse and dry. By using 1 lb. of the dye-stuff in the same way a light red shade is got.

Orange.—Dye at the boil for one hour with 1 lb. Chrysamine G, 3 lb. soap and 10 lb. Glauber's salt, then rinse and fix in a fresh boiling bath with 1 lb. bichromate of potash, 3 lb. sulphate of copper and 2 lb. acetic acid.

Yellow.—Dye with 3-1/2 lb. Diamine yellow N, 3 lb. soap and 15 lb. phosphate of soda, then fix with 4 lb. fluoride of chromium.

Gold Yellow.—Prepare the dye-bath with 3 lb. Benzo chrome brown 5 G, 1 lb. soda ash, 12 lb. Glauber's salt. Dye at the boil for one hour and rinse. This gives an orange brown. To get the yellow shade, afterwards chrome with 3 lb. bichromate of potash, 3 lb. sulphate of copper, 1 lb. acetic acid, in a fresh bath. Enter at about 130 deg. F., bring to the boil, and boil for half an hour.

Pale Leaf Green.—Dye with 3 lb. Dianil yellow 3 G, 1 lb. Dianil yellow R, 1 lb. Dianil blue G, and 20 lb. salt, then fix with 3 lb. copper sulphate and 2 lb. acetic acid.

Leaf Green.—Dye with 3 lb. Dianil yellow 3 G, 3 lb. Dianil blue G, and 20 lb. salt, fixing with 4 lb. copper sulphate and 2 lb. acetic acid.

Dark Green.—Dye with 2 lb. Dianil yellow R, 1-1/2 lb. Dianil dark blue R, 1 lb. soda and 20 lb. salt, fixing with 3 lb. copper sulphate.

Pale Olive Green.—Dye with 2-3/4 lb. Diamine fast yellow B, 1-1/4 lb. Diamine blue R W, 3/4 lb. Diamine blue R W, 3/4 lb. Diamine catechine G; fix with 4 lb. sulphate of copper and 2 lb. acetic acid.

Russia Green.—Dye with 2-1/2 lb. Diamine blue R W, 10 oz. Diamine dark blue B, 2-1/2 lb. Diamine fast yellow B, 3 lb. soda and 20 lb. Glauber's salt; fix with 4 lb. sulphate of copper and 2 lb. acetic acid.

Blue Green.—Dye with 1-3/4 lb. Diamine sky blue F F, 6 oz. Diamine fast yellow B, 1 lb. soda and 10 lb. Glauber's salt; fix with 2 lb. sulphate of copper and 1 lb. acetic acid.

Bronze Green.—Use in the bath at the boil 4 lb. Diamine bronze G, 2 lb. soda and 10 lb. Glauber's salt, then fix with 4 lb. fluoride of chromium.

Pea Green.—Dye in a boiling bath with 1/2 lb. Diamine sky blue F F, 2-1/4 lb. Diamine fast yellow A, 1 lb. soda and 10 lb. Glauber's salt, then fix in a fresh bath with 2 lb. sulphate of copper and 1 lb. acetic acid.

Leaf Green.—Dye at the boil for one hour in a bath containing 2-3/4 lb. Diamine fast yellow B, 1-3/4 lb. Diamine blue R W, 7 oz. Diamine catechine B, 2 lb. soda and 20 lb. Glauber's salt, then fix in a new bath with 4 lb. sulphate of copper and 2 lb. acetic acid.

Light Green.—Prepare the dye-bath with 7-1/4 oz. Diamine blue R W, 5-1/2 oz. Diamine orange B, 2 lb. Diamine fast yellow B, 1 lb. soda and 10 lb. Glauber's salt, work at the boil for one hour, then treat in a fresh bath with 3 lb. sulphate of copper.

Olive Green.—Dye with 2-1/4 lb. Chicago blue R W, 15 oz. Chrysamine G, 2 lb. soda and 10 lb. Glauber's salt; fix with 1 lb. bichromate of potash, 3 lb. sulphate of copper and 2 lb. acetic acid.

Pea Green.—Use in the dye-bath 3 lb. Chrysophenine G, 1 lb. Chicago blue 6 B, 2 lb. soda and 10 lb. Glauber's salt, working at the boil for one hour, then fix in a fresh boiling bath with 3 lb. sulphate of copper and 2 lb. acetic acid.

Green.—Dye with 2-3/4 lb. Chicago blue 6 B, 5 oz. Chrysamine G, 2 lb. soap and 20 lb. Glauber's salt; fix with 1 lb. bichromate of potash, 3 lb. sulphate of copper and 2 lb. acetic acid.