DYEING. 



MMta 



Ukc. 



how clfoct- 

 d by 



left. Fixed alkali t'ornn, with this solution, a violt-t ; 

 ^ e sulphuric acid, a lawn-colour! <1 : ami the Milphatc 

 of potash, a liiu- red precipitate. Precipitates of va- 

 rious shades may be obtained by nluin, nitre, chalk, ace- 

 titc of lead, and muriate of tin. The infusion of tin- 

 best Zealand madder, * solution of alum having IHVII 

 previously added to it, affords, with alkaline carbon- 

 ates, a lake of a blood-red colour, which has greater in- 

 less intensity, according to the quantity of alum that 

 has been dissolved in it. This lake is transparent in 

 oil, but with water it is opaque, and destitute of beau- 

 ty. Calcareous earth precipitates a more dark and 

 brown-coloured lake than alkalies, particularly if em- 

 ployed in the form of lime-water. The carbonate of 

 magnesia produces with alum a clear blood-red extract . 

 which readily dissolves in water. 



125. D'Ambourney and some others pretend, tluit 

 the roots of madder may be used with greater advan- 

 tage when they are freshly gathered, than after they 

 have been kept for some time, and reduced to the state 

 of powder. This assertion, however, is by no menus 

 countenanced by the general experience of practical 

 dyers, who find, that, if properly dried, and carefully 

 preserved from moisture, madder improves by keeping, 

 at least during the two first years. 



126. The colour yielded by the chay, chayaver of the 

 Tamuls, which l)r Roxburgh has ascertained to be a spe- 

 cies of oldenlandia, is nearly allied to that of madder. 

 This plant is a small biennial, rarely a triennial, grow- 

 ing spontaneously on light sandy soils, and extensively 

 cultivated on the Coromandel coast The cultivated 

 roots are very slender, and from one to two feet in 

 length ; the wild are shorter, and yield more colouring 

 matter, which is also of a superior quality. The co- 

 lour, which is of an orange hue, seems to reside almost 

 entirely in the bark of the roots. 



YUMs a co- 127- The chay root is said to be extensively employ- 

 lour infirior ed as a dye in India ; but the colours obtained from it, 

 ft madder, jjy those who have examined its properties in this coun- 

 try, do not warrant us to recommend its importation. 

 Dr Bancroft states, that the best specimens of it which 

 he could procure, did not seem, in any instance, to 

 yield a colour superior to that of madder, but, in gene- 

 ral, greatly inferior both in beauty and durability. With 

 the solutions of tin, it produced a very bright and last- 

 ing red on wool ; though, like that of madder, it incli- 

 ned too much to the orange. With the oxides of iron 

 it produced nothing darker than drab colours, either 

 upon wool or cotton. Broad cloth dyed without any 

 basis, acquired from chay root a brownish red, which 

 was neither so bright nor so durable as that which it 

 assumes in the same way from madder. 



128. The colouring matter yielded by the roots of 

 galium, a genus of plants belonging to the same order 

 as the preceding, differs but little from that of madder ; 

 only when the brown external covering of the root is 

 removed, the colour which it imparts to wool is some- 

 what brighter, with an aluminous basis. The several 

 species of galium chiefly employed in dyeing, are the 

 following: Galiura tinctorium, galium verum, galium 

 mollugo, galium sylvaticum, galium boreale, galium 

 aparine. The galium tinctorium i* found in great 

 abundance in the woods of North America, and its 

 roots are employed by the native inhabitants to dye 

 porcupine quills of a red colour. The galium verum, 

 yellow ladies' bed-strati', or cheese routing, affords a co- 

 lour which is but little inferior to the scarlets dyed 

 with cochineal. The roots, which afford the colouring 

 matter, are covered by a very dark bark, wliieh mutt be 



Cilium. 



removed, to prevent it* fiffi.'Ctin.<r the colour of the re?t Ailj 

 of the root. The dv<- thus olifiint-d is employed bv the l "lu"i>g 

 people <>!' the Highlands, and of some of the {.-.lands ' M 

 of Scotl.md, lor giving a bright red to their woollen *"""V~ 

 stuffs. The galium niollug<> and the gnliuin sylvati- 

 cum, yield a colour equally bright and lasting." The 

 galium boreale is said to afford a more brilliant red 

 than any other .species. Its roots are used as a dye \<\ 

 the inhabitants of Sw it/erland. The galium a|uirine. 

 common rough lail'irs /(/-..'/<//<-, i7rir;., or goose grass. 

 aKo afford ; a ivd dye, but inferior to the last. Dr '. 

 croft has noticed a \ triety of other colouring matters 

 nearly allied to madder, but their properties are too mi- 

 important to merit consideration in this work ; we shall 

 therefore now proceed to make some observations on 

 Brazil wood. 



li'y. Brazil wood, as an article used in dyeing, is nraia 

 the heart, or central part, of a large tree which grows wooJ. 

 in Brazil. Bcrthollct states, tliat it derives its name 

 from that part of South America; but Dr Bancroft has 

 decidedly proved, that the country took its name from 

 die wood, not the wood from the country. Brazil 

 wood is mentioned in some old charters, particularly 

 one dated in ll'JS, and another in 1300', under t he- 

 name of Braxilis, which, as well as l>ra.silis, is under- 

 stood to be derived from bragio, a burning coal, to de- 

 note its fiery red, or flame colour. It is also crllcd 

 Feniambucca, wood /"</ Martha, of Japan, and of .SVi- 

 pan. Linnaeus describes the tree which furnishes Bra- 

 zil wood under the name Casalpina critlii ; that which 

 gives the Japan or sapan wood, by the name Cccsalpina 

 sti/i/>:ii ; and that of Antilles, wliich is the least esteem- 

 ed, he calls Ca'talpiiin raiciiria. That wliich comes 

 from Fernambucca is the most valuable. 



130. Brazil wood is very hard, and takes a good po- Solvents of 

 lish. It is pale when first cut, but reddens by expo- Brazil 

 sure to the air. It sinks in water, and its goodness is *'"- 

 known by its weight. Boiling water extracts the whole 



of its colouring matter, and becomes of a fine red if 

 the boiling be continued sufficiently long. A black re- 

 siduum remains, which still yields much colouring 

 matter to alkalies. A more perfect solution is obtained 

 by alcohol, and also by ammonia ; at least the colour is 

 deeper. The practice of sprinkling the powder of Bra- 

 zil wood, during the operation of grinding it, with stale 

 virine, probably raises the colour, by means of the vola- 

 tile alkali which it contains. 



131. Fresh decoction of Brazil wood yields, by the Effect* of 

 addition of sulphuric acid, a small quantity of a red different 

 precipitate, inclining to fawn colour ; thejliquor remains agcm upoa 

 yellow and transparent. Nitric acid renders the liquor the olutio. 

 yellow at first; but if more be added, the liquor ac- 

 quires a deep orange colour, and becomes transparent, 



after having deposited a precipitate nearly resembling 

 the former in colour, but more copious. .Muriatic acid 

 produces the same effects as the sulphuric. Oxalic- 

 acid produces a precipitate of an orange red, nearly as 

 copious as the nitric acid does. The liquor remains 

 transparent, and of the same colour as in the former 

 trials. Distilled vinegar gives a very little precipitate of 

 the same colour: the liquor remaining transparent, and 

 ,1 little more inclining to orange. Tartar furnMi',-.- still 

 less precipitate, and leaves the liquor turbid. Fixed 

 alkali restores the decoction to a crimson, or deep \ -iol.t 

 inclining to brown. Ammoniac gives a brighter pur- 

 ple, or violet, and a little precipitate of a fine purple. 

 Alum occasions a red precipitate inclining to crimson : 

 the liquor also affords a copious precipitate on saturating 

 the acid of the alum with an alkali. In tliis way an 



