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Petersburgh, by a canal which joins it to the Proper names, when familiarized in English, river Louat, and is navigable throughout. dwindle to monosyllables; whereas in other lanDwina, another large river of Russia, is formed guages they receive a softer turn, by the addition of

Addison. by the union of the Juchona and Jug, near the a new syllable. town of Ustjug, in the government of Vologda. Physicians, with their milky cheer, It falls, by two arms, into the White Sea, a little The love-sick maid and dwindling beau repair. 10 the north-west of Archangel, and is a broad

Gay. and deep stream, but its mouths are choked with Religious societies, though begun with excellent mud.

intentions, are suid to have dwindled into factious DWIN'DLE, 0.n. Sax. dwinan; Dut, clubs.

Swift. Dwin'dLED, adj. I dwynen ; Isl. dwyna.. He found the expected council was dwindling into a To decay; to shrink; wear away; degenerate: conventicle, a packed assembly of Italian bishops, as an active verb, to make less; to break down, not a free convention of fathers.

Atterbury. or into parts ; disperse.

Our drooping days are dwindled down to nought, Weary sev'n'nights nine times nine,

Their period finished ere 't is well begun. Thomson. Shall be dwindle, peak, and piue.

Lost in thoughtless ease and empty show,
Shakspeare. Macbeth.

Behold the warrior dwindled to a beau;
Under Greenvil, there were only five hundred fnnt Since freedom, piety, refined away,
and three hundred horse left; the rest were dwindled Of France the mimick, and of Spain the prey.
Clarendon.

Johnson. London. Thy dwindled legs seem crawling to the grave.

Dryden.

In its preventive police it ought to be sparing of its We see, that some small part of the foot being in- efforts, and to employ means, rather few, unfrequent,

and strong, jured by a wrench or a blow, the whole leg or thigh

than many, and frequent, and, of course, thereby loses its strength and nourishment, and

as they multiply their puny politic race, and dwindle, dwindles away.

Locke.
small and feeble.

Burke. If there have been such a gradual diminution of Will they thank the noble lord for reminding us the generative faculty of the earth, that ic hath dwin- how soon these lofty professions dwindled into little dled from nobler animals to puny mice and insects, jobbing pursuits for followers and dependants, as unwhy was there not the like decay in the production of fit to fill the offices procured for them, as the offices vegetables ?

Bentley. themselves were unfit to be created. Sheridan.

away.

D Y EIN G.

DYE, d. a. & n. s. Sax, deagan, to color. There were some of very low rank and professions DYER, n. s.

Often written die. To who acquired great estates: cobblers, diers, and shoeDye'ıng.

tinge; color; stain. makers gave publick shows to the people, His looke was sterne, and seemed still to threat

Arbuthnot on Coins. Cruell revenge, which he in hart did hyde,

It is surprizing to see the images of the mind And on his shield Sansloy in blood lines was dyde.

stamped upon the aspect; to see the cheeks take the Spenser. Faerie Queene.

die of the passions, and appear in all the colours of thought.

Collier of the Aspect. It will help me nothing

Flowers fresh in hue, and many in their class,
To plead mine innocence; for that die is on me,
Which makes

Implore the pausing step, and with their dyes
my
whit'st

part
black.

Dance in the soft breeze in a fairy mass. Byron.
Shakspeare. Henry VIII.
We have dainty works of feathers of wonderful

PART I. lastre, excellent dies, and many.

THE THEORY OF DYEING.
Bacon's New Atlantis.
So much of death her thoughts

1. Dyeing is a chemical art which has for its Had entertained, as died her cheeks with pale.

object the extracting of the coloring particles Milton.

from such substances as afford them, and transHe (an obstinate man) will rather suffer self-mar- ferring them to certain stuffs of wool, silk, cotton, tyrdorn than part with the least scruple of his free or linen. No art has profited so much from the hold; for it is impossible to dye his dark ignorance improvements of modern chemistry as the art of into a lighter color.

Butler. dyeing has ; and it cannot be, nor ought it to be A translator dyes an author, like an old stuff into a forgotten, that while we owe much to the disconew colour, but can never give it the lustre of the veries of our own countrymen, and the applicafirst tincture ; al .-ks that are twice dyed lose their tion of those discoveries to the useful arts, the glosses, and never receive a fair color.

Id.

art of dyeing is highly indebted to the national The fleece, that bas been by the dier stained,

operations of the French chemists. Never again its native whiteness gained. Waller.

2. The origin of this art seems to be of high All white, a virgin saint she sought the skies;

antiquity; a circumstance which renders it imlor marriage, though it sallies not, it dies. Dryden.

possible to say to whoin or to what it is to be Darkness we see emerges into light, And shining suns descend to sable night :

attributed : conjecture, therefore, is all we can Even heaven itself receives another die,

pretend to. As most of the materials from which When wearied animals in slumbers lie

coloring matter is derived are, of themselves, Of midnight ease; another, when the grey

either of dark and disagreeable colors, or else Of morn preludes the splendour of the day. destitute of any particular color, it is probable

Id. that, even in the very earliest ages, the love of

ornament, which is natural to mankind, and tions were finished, a piece of white wool was which is founded on the love of distinction, one immersed, by which means they ascertained of the most active principles of the human mind, whether the liquor had acquired the proper shade. would induce them to stain their vestments with Various processes were followed to prepare the various coloring ingredients, especially with stuff to receive the dye. By some it was imvegetable juices But the means of imparting mersed in lime-water, and by others it was prepermanent dyes to cloth, and affixing to its fibres pared with a kind of fucus, which acted as a such coloring materials, as could not easily be mordant to give it a more fixed color. Alkanet washed out by water, or be obliterated or greatly was used by some for the same purpose. The changed by the action of air, or of certain saline liquor of the whelk did not alone yield a durable substances, to which they are liable to be exposed, dolor. The liquor from the other shell-fish served and which are necessary to render them clean to increase its brightnesss ; and thus two operawhen soiled, was an art which required the know- tions were in use to communicate this color. A ledge of principles not within the reach of untu- first dye was given by the liquor of the purple, tored men, and only to be obtained by gradual and a second by that of the whelk; from which investigation, and by the lapse of a considerable it was called by Pliny purpura dibapha, or purportion of time.

ple twice dipped. The small quantity of liquor 3. According to Pliny, the Egyptians had dis- which could be obtained from each shell-fish, and covered a mode of dyeing, somewhat resem- the tedious process of its preparation and applibling that which we use for coloring printed cation to the stuffs, raised the price of purple so linens: the stuffs, probably after having been im- high, that in the time of Augustus a pound of pregnated with different mordants, were immersed wool of the Tyrian purple dye, could not be purin vats, where they received various colors. And chased for one thousand denarii, equal to about M. Delaval is of opinion, that they were pos- £36 sterling. sessed not only of the art of dyeing, but even of 5. Among the Greeks the knowledge of dyeing that of printing on cloths.

must have been very imperfect, and little assisted 4. The Phænicians seem to have a strong by science; for the art of dyeing linen appears claim to the invention of this art, and they held a not to have been known in Greece before Alexdecided pre-eminence in the practise of it for ander's invasion of India, where, according to many ages : their purple and scarlet cloths were Pliny, they dyed the sails of his vessels of difsought after by every civilised nation; and the ferent colors. The Greeks seem to have borrowed city of Tyre, enriched by its commerce, increased this art from the Indians. to an amazing extent. But her career was 6. India seems to have been the nursery of the stopped by the vanity and folly of the eastern arts and sciences, which were afterwards spread emperors; under whose dominion this opulent and perfected among other nations. Accidents, city had unfortunately fallen. Desirous of mo which had a tendency to improve the art, could nopolising the wearing of the beautiful cloths of not fail to be multiplied rapidly, in a country, Tyre, these tyrants issued most severe edicts, -rich in natural productions; requiring little labor prohibiting any one from appearing in the Tyrian for the support of its inhabitants; and the popublue, purple, or scarlet, except themselves, and lation of which was favored by the bounty' of their great officers of state. To this injudicious nature, and simplicity of manners, till it was oprestriction is to be attributed the destruction of posed by the tyranny of succeeding conquerors. the Tyrian dyes. For under the impolitic But religious prejudices, and the unalterable direstraint imposed on the consumption of the vision into castes, soon shackled industry; the arts Phænician cloths, the manufacturers and dyers became stationary; and it would seem, that the were no longer able to carry on their trade; it knowledge of dyeing cotton in that country (for grew languid and expired : and, with the trade, silk was then unknown, or at least very scarce) the art itself also perished. It is generally sup was as far advanced in the time of Alexander, as posed from the name, that the Tyrian purple, so it is at the present period. much celebrated among the ancients, was disco 7. The beautiful colors, which are observable vered at Tyre, and that it contributed not a little in some Indian linens, would lead one to suppose to the opulence of that celebrated city. The that the art of dyeing had there attained a high liquor which was employed in dyeing the purple degree of perfection; but we find by the descripwas extracted from two kinds of shell-fish, one tion which Beaulieu, at the request of Dufay, of which, the larger, was called the purple, and gave of some operations performed under his own the other was a species of whelk. Each of these eye, that the Indian processes are so complicated, species was subdivided into different varieties, tedious, and imperfect

, that they would be imwhich were otherwise distinguished, according to practicable in any other country, on account of the places where they were found, and as they the great difference in the price which is paid for yielded more or less of a beautiful color. It is labor. in a vessel in the throat of the fish that the color 8. It is unquestionably true, that European ining liquor is found. Each fish only afforded a dustry has far surpassed them in correctness of single drop. When a certain quantity of the design, variety of shade, and facility of execuliquor had been obtained, it was mixed with a tion; and, if we are inferior to them with respect proportion of common salt, macerated together to the liveliness of some colors, it is only to be for three days, and five times the quantity of attributed to the superior quality of some of their water added.

The mixture being kept in a mo- dyes, or perhaps to the length and multiplicity derate heat, animal parts which happened to of their operations and processes.

In our own be mixed with it separated, and rose to the sur- country, however, the art of dyeing made no conface. At the end of ten days, when these opera- siderable progress till about the beginning of the

seventeenth century.

Before that period our referred the phenomena of dyeing entirely to cloths were sent to Holland, to be dressed and chemical principles. Having dyed some wool dyed. This, however, was probably practised and some silk in a solution of indigo, in very only in the case of particular colors. The dyeing dilute sulphuric acid, he explains the effects he of woollen and silken goods has indeed long since observed in the operation, by attributing them to attained a considerable degree of excellence; the precipitation, occasioned by the blue particles but the manufactures of cotton, owing to the having a greater affinity for the particles of small attraction of that substance for coloring the wool and silk, than for those of the acidumatters, have been very, deficient in this point. lated water. He remarks that this affinity of the Till within these few years, the colors employed wool is so strong, as to deprive the liquor enin the dyeing of fustians and cotton velvets were tirely of the coloring particles; but that the few; and, even at this day, many of them are weaker affinity of the silk can only diminish the fugitive. But it must be allowed that great im- proportion of these particles in the bath , and he provements have been made within these few shows that on these different affinities depend years, from the application of chemical principles, both the permanence and intensity of the color. and by a diligent investigation of the nature of 12. This is the true light in which the phecoloring substances. There is however still much nomena of dyeing should be viewed; they are room for the improvement of the art, but this can real chemical phenomena, which ought to be only be effected by the practical dyer acquiring analysed in the same way as all those dependent chemical knowledge, an acquisition now happily on the actions which bodies exert, in conseplaced within the reach of every dyer who is quence of their peculiar nature. It is evident, capable of reading and understanding the En- that the coloring particles of bodies possess cheglish language. It will not be necessary for our mical properties, that distinguish them from all present purpose to enter into a minute examina- other substances; and that they have attractions tion of the various theories that have been ad- peculiar to themselves, by means of which they vanced of the nature of colors; at the same time unite with acids, alkalis, metallic oxides, or calces, it may be proper, before we deduce a general and some earths, principally alumine or pure theory of dyeing, to make a few observations on clay. They frequently precipitate oxides and the common properties of coloring substances. alumine, from the acids which held them in so

9. In explaining the cause of color, and the lution; at other times they unite with the salts, nature of coloring particles, two great inconveni- and form supercompounds which combine with ences have arisen. First, from an attempt to illus- the wool, silk, cotton, or linen. And with these trate the action, which the particles of coloring their union is rendered much more close by substances have on the rays of light, in conse means of alumine or metallic oxide, than it would quence of their density and thickness, without be without their intermedium. having any means of ascertaining this, and 13. The difference in the affinity the colorwithout any regard to the attractions which resulting particles for wool, silk, and cotton, is somefrom their chemical composition; in comparing times so great, that they will not unite with one the coloring particles to mucilages and resins, of these substances, while they combine very from some very faint resemblances; and in at- readily with another; thus, cotton receives no tempting to explain their coloring properties by color in a bath which dies wool scarlet. Dufay conjectures, formed respecting their component prepared a piece of stuff, the warp of which was parts, while these properties ought rather to be wool and the woof cotton, which went through ascertained by direct experiment than explained the process of fulling, that he might be certain, by an imaginary composition. It was also de- that the wool and the cotton received exactly thé parting from true theory, to ascribe to laws same preparation; but the wool took the scarlet purely mechanical, the adhesion of the coloring dye, and the cotton remained white. It is this particles to the substances dyed, the action of the difference of affinity which renders it necessary mordants, the difference between the true or du- to vary the preparation and the process, accordrable, and the false or fugitive dyes.

ing to the nature of the substance which is in10. Hellot, who has written an excellent trea- tended to be dyed of a particular color. And tise on dyeing, seems to have erred on this these considerations ought to determine the subject; and Macquer, who was amongst the first means to be pursued for the improvement of the who entertained just notions respecting chemi- art of dyeing. It is highly proper to endeacal attractions, seems to have been led astray by vour to ascertain what are the constituent prinhis ideas. It appears, however, that Dufay had ciples the coloring particles. And in this enbefore observed, that the coloring particles were quiry, the most essential circumstances are, to naturally disposed to adhere more or less firmly determine the affinities of a coloring substance ; to the filaments which receive them; and had first, with the substances which may be employed very justly remarked, that without this disposition, as menstrua; secondly, with those which may, by stuffs would never assume any color but that of their combinations, modify the color, increase its the bath, and would always divide the coloring brilliancy, and help to strengthen its union with particles equally with it: whereas the liquor of the stuff to be dyed ; thirdly, with the different the bath sometimes becomes as limpid as water, agents which may change the color, and princigiving off all the coloring particles to the stuff; pally with the external agents—air and light. which, he observes, seems to indicate that the in 14. The qualities of the uncombined coloring gredients have less attraction for the water than particles are modified when they unite with a for the particles of the wool.

substance; and, if this compound unites with a 11. Bergman seems to have been the first who stuff, it undergoes new modifications. Thus the

cess.

properties of the coloring particles of cochineal alkalis, earths, and metallic oxides, which conare modified, by being combined with the oxide stitute a part of their chemical properties; and in of tin, and those of the substances resulting from consequence of which, their colors are more or this combination are again modified by their less varied; therefore these particles form, with union with the wool or silk; so that the know- the stuff on which they are fixed, a compound ledge we may acquire by the examination of which retains only some of their original propercoloring substances in their separate states, can ties; they are also modified by their union with only inform us respecting the preparations that alumine, or pure clay, metallic oxides, and some may be made of them; that which we acquire other substances; as are also those new comrespecting weir combinations with substances pounds, when they are further combined with which serve to fix them, or to increase their the stuff. beauty, may inform us what processes in dyeing

OF MORDANTS. ought to be preferred or tried; but it is only by direct experiment made with the different sub 18. The term mordant is derived from the stances employed in dyeing, that we can confirm French word mordre, which signifies to bite our conjectures, and properly establish the pro- or corrode. In the art of dyeing, it is applied

to designate all those substances employed for 15. These facts show, that the changes pro- the purpose of facilitating or modifying the duced by acids and alkalis on many vegetable combination of the coloring particles with the colors, such as the chemists employ, in order to stuff dyed. Dr. Bancroft, and Dr. Henry of discover the nature of different substances, are Manchester, proposed to denominate these subowing to the combinations, which take place be- stances by the term basis, since the action of tween these coloring particles and the acids and many of them does not depend on the acid or alkalis. The compounds resulting from these may corroding principle; but this alteration has not be compared to neutral salts, which possess qua- been adopied. Mordants deserve the greatest lities different from those of their component parts, attention; as by their means colors are varied, but in which one of these parts may be in excess, brightened, made to strike, and rendered more and its qualities consequently predominant. durable. We shall, therefore, examine the naThis state of combination is observable between ture of the action of the principal bases or morthe coloring particles of cochineal and acidulous dants, and endeavour to determine how their attartrite of potassa, or cream of tartar: by evapo- tractions serve to unite the coloring particles with rating slowly a solution of this salt in a decoction the stuff, and how they affect the qualities of the of cochineal, crystals are formed, which retain colors. a fine ruby color, much more bright and intense 19. A mordant is not always a simple agent, than that of the liquor which formed them. for new combinations are sometimes formed by the

16. It was the opinion of Berthollet that some ingredients that compose it; so that the subof the acids, particularly the nitric, after combin- stances employed are not the immediate agents, but ing with the coloring particles, changed the the compounds which they have formed. Somecolor which they at first produced, making it times the mordant is fixed with the coloring paryellow, and finally destroying it; after which ticles, and sometimes the stuff is impregnated they act by means of one of their principles, viz. with it; on other occasions, both these modes the oxygen. But this theory, Dr. Ure remarks, are united ; and we may dye successively with is not now tenable, since it is known that liquors containing different substances, the last dry chlorine does not blanch dry litmus paper. of which only can act on the particles with which When moisture intervenes, muriatic acid is the stuff is impregnated. The art of printing linen formed, and oxygen evolved; to the action of affords many processes, in which it is easy to obwhich body on the color the bleaching effect is serve the effects of mordants; to elucidate this to be ascribed. Water is the source of the dis- subject, therefore, we shall mention a few excoloration, both in the ancient and modern pro- amples. cess of bleaching. Blue colors are not the only 20. The basis employed for linens intended to ones which become red by the addition of acids, receive different shades of red, is prepared by and green by that of alkalis; most red colors, as dissolving in eight pounds of hot water, three that of the rose, for instance, are heightened by pounds of alum, and one pound of acetate of acids, and made green by alkalis; and some lead, or sugar of lead, to which two ounces of green colors, such as that of the green decoction potassa, and afterwards two ounces of powdered of burdock, according to the experiments of Mr. chalk are added. The alum is decomposed by Nose, and the green juice of Buckthorn, as is the acetite of lead, because the oxide or calx of evident from the trials of Mr. Becker, are red- lead combines with the sulphuric or vitriolic dened by acids.

acid, and forms an insoluble salt which is pre17. This property, which is common to most cipitated; the base of the alum, alumine, at the of the ordinary colors of vegetables, seems to prove same time combines with the acetous acid, or that there is a close analogy between their color- vinegar, and produces an acetite of alumine ; and ing particles; and it is not without foundation, the chalk and potassa answer the purpose of satuthat Linnæus supposed, that the red in vegetables rating the excess of acid. One of the advantages was owing to an acid, and indicated its presence; which result from the formation of the acetite but there are also many vegetables which contain of alumine is, that the alumine is retained in it acid in a disengaged state, without their possess- by a much weaker affinity than in the alum; so ing a red color. It is therefore evident, that the that it more easily quits its menstruum, to comcoloring particles have affinities for acids, bine with the stuff and coloring particles. Another

having the

advantage is, that the acid liquor, from which duces a decomposition and new combinations. alumine is separated, has much less action on the But even this effect is sometimes incomplete, color when it consists of the acetous, than when or does not at all take place without the action it consists of a stronger acid, such as the sul- of another affinity, namely, that of the coloring phuric. In short, the acetite of alumine not particles. We have an example of this in the

property of crystallising, the mordant, mixture of alum and tartar, which is one of the which is thickened with starch or gum, to pre- most common inordants in the dyeing of wool. pare it for being applied to the block on which 22. M. Berthollet, having dissolved equal the design is engraved, does not curdle, as it weights of alum and tartar, found that the soluwould if it contained alum capable of crystallis- bility of the tartar was increased by the mixture. ing. By attending to the operation performed By evaporation and a second crystallisation, the upon a piece of linen cloth, we find, that when two salts were separated, so that no decomposiit has been impregnated by the mordant, in the tion had taken place. Half an ounce of alum manner determined by the design, it is put into and one ounce of wool were then boiled together a bath of madder; the whole of the cloth be- for an hour, and a precipitate was formed, which, comes colored, but the tinge is deeper in those being carefully wasbed, was found to consist of parts which have received the mordant; there filaments of wool incrusted with earth. To this the coloring particles have combined with the sulphuric acid was added, and the solution being alumine and the cotton, so that a triple com- evaporated to dryness, crystals of alum were pound has been formed, and the acetous acid produced, with the separation of some particles separated from its basis remains in the bath. of carbonaceous matter. The liquid in 'which

Thus the coloring particles, combined with the wool had been boiled being evaporated, the alumine and the stuff, are much more diffi- yielded only a few grains of alum; what recultly affected by external agents, than when they mained would not crystallise. This being again are in a separate state, or combined only with the dissolved, and precipitated by means of an alkali, stuff, without any intermediate bond of union; the alumina which was thrown down was of a slate and on this property the operations, to which the color, became black when placed on red-hot coals, cloth is afterwards subjected, are founded. After and enitted alkaline vapors. From this experiment it has been maddered, it is boiled with bran, and it appears that the alum was decomposed by the spread upon the grass; and these operations are wool, and that part of the alumina had combined alternately repeated until the ground becomes with its most detached filaments which were least white. The coloring particles, which have not retained by the force of aggregation; that part united with the alumine, are altered in their com- of its animal substance had been dissolved and position, dissolved, and separated, while those precipitated by the alkali from the triple comthat have combined with it remain, and are pre- pound thus formied. served, without alteration; and thus, the design 23. M. Berthollet made the same experiment alone remains colored. It seems that this de- with half an ounce of alum and two drams of composition of the coloring particles, by ex tartar; no precipitation took place : he obtained posure on the grass and boiling with bran, is by evaporation a small portion of tartar, and accomplished in the same manner as that of the some very irregular crystals of alum; the recoloring particles of flax, and admits of the same mainder would not crystallise: this, on being diexplanation. The only difference consists in sub- luted with water, and precipitated by potassa, stituting bran for alkalis, because they would dis- gave by evaporation a salt which burned like solve a part of the coloring matter, which is fixed by tartar. The wool which had been boiled with the the aluinine, and would change its color; instead alum felt harsh, but the other retained its softof which, the bran, having a much weaker action The first had acquired from the madder a on this substance, affects only the coloring par- more dull, though lighter tint, but the color of ticles, which, by the action of the air, have been the latter was more full and bright. disposed more easily to solution. If, however, 24. From these experiments it appears, in the instead of the mordant, a solution of iron be em first place, that the wool had begun a decomposiployed, similar phenomena are exhibited. The tion of the alum; that it had united with a part coloring particles decompose the solution of iron, of the alumine; and that even the part of the and form a triple compound with the stuff; but, alum which retained its alumine had dissolved instead of red, we obtain from the madder, brown some of the animal matter. In the second place, colors of different shades, down even to black; that the tartar and alum, which cannot decomand, by uniting these two mordants, alum and pose each other solely by their own affinities, iron, we have mixed colors, inclining to red on become capable of acting on each other when the one hand, and to black on the other, such as their affinities are assisted by that of the wool. mordoré, and puce color. Other colors are also And, in the third place, that the tartar appears procured by substituting dyers-weed for madder; principally useful for moderating the too powerand by means of these two coloring substances, ful action of the alum upon the wool, whereby indigo, and the two mordants above mentioned, it is injured ; for tartar is not used in the alumwe obtain most of the different shades that are ing of silk and thread, which have less action on observable in stuffs which are printed.

the alum than wool has. As the decomposition 21. The different substances which enter into of alum by the tartar and wool takes place in the composition of a mordant remain in combi- consequence of affinities' which nearly balance nation till a new action is induced by the appli- each other, and the process must therefore go on cation of another substance. Thus the affinity slowly, it is useful to keep the stuff impregnated of the stuff for one of their constituent parts pro- with alum and tartar for some days in a moist Vol. VII

2 P

ness,

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