152 ' 
D Y I N G. 
matter to water. The infufion is of a brownifh orange 
colour; alum produces in it a deep brownifh red preci¬ 
pitate; alkaline carbonats, a blood-red precipitate, which 
is re-diiTblved on adding more alkali. The precipitate 
occalioned by acetite of lead is brownifh red ; by nitrat 
of mercury, purplifh brown; by fulplut of iron, a fine 
bright brown. After the red colouring matter has been 
extracted from madder by water, it is ftill capable of 
yielding a brown colour. 
Carthamus tinElorius is. an annual plant, cultivated 
in Spain, Egypt, and the Levant, for the fake of its 
flowers, which alone are ufed in dying. After the 
nice has been fqueezed out of thcl'e flowers, they are 
waffled repeatedly with fait water, prefTed between 
the hands, and fpread on mats to dry. Care is taken 
to cover them from the fun during the day, and to 
expofe them to the evening dews, in order to prevent 
them from drying too faff. Such is the method followed 
in Egypt. The flowers of carthamus contain two 
colouring matters; a ..yellow, which is foluble in water, 
and a red, infoluble in water, but foluble in alkaline 
carbonats. The method of preparing them above de¬ 
fended, is intended to carry off the yellow colouring 
matter, which is of no ufe, and to leave only the red. 
After the flowers are thus prepared, they are of a red 
colour, and have loft nearly one-half of their weight. 
An alkaline ley readily extracts their colouring matter, 
which may be precipitated by faturating the alkali with 
an acid. Lemon juice is comtnoniy ufed for this pur- 
pofe, becaufe it does not injure the colour of the dye. 
Next to citric, fulphuric acid is tube preferred, provided 
too great a quantity be not ufed. The red colouring 
matter of carthamus, extracted by carbonat of foda, and 
precipitated by lemon juice, conftitutes the rouge em¬ 
ployed by the ladies as a face-paint. It is afterwards 
ground with a certain quantity of talc. The finenefs of 
the talc, and the proportion of it mixed with the car¬ 
thamus, occafion the difference between the cheaper and 
dearer kinds of rouge. 
Brazil wood, or fernambouc, as it is called by the 
French, is the wood of the ccefalpinia crifia, a tree which 
grows naturally in America and the Welt Indian iflands. 
It is very hard ; its fpecific gravity is greater than that 
of water; its tafte is fweetilh : its colour, when frefli 
cut, is pale ; but after expofure to the atmofphere, it 
becomes reddifh. Brazil wood yields its colouring 
matter to alcohol, and likewife to boiling water. The 
decoftion is of a fine red colour. The mineral acids 
make it yellow, and occafion a reddifh brown precipitate. 
Oxalic acid caufes an orange red precipitate. Fixed 
alkali gives the decoction a crimfon colour, inclining to 
brown ; ammonia, bright purple. Alum occafions a 
copious crimfon precipitate, efpecially if alkali is added 
at the fame time. Sulphat of iron renders the decoftion 
black. The precipitate produced by muriat of tin is 
rofe-coloured ; that by acetite of lead of a fine deep 
red. The decoftion of Brazil wood is fitter for dying 
after it has flood fome time, and undergone a kind of 
fermentation. 
None of the red colouring matters has fo flrong an 
affinity for cloth as to produce a permanent red, without 
the afliftance of mordants. The mordants employed are 
alumina and oxyd of tin ; oil and tan, in certain pro- 
celfes, are alfo ufed; and tartar and muriat of foda are 
frequently called in as auxiliaries. Coarfe woollen fluffs 
are dyed red with madder or archil ; but fine cloth is 
almofl exclufively dyed with cochineal ; though the 
colour which it receives from kermes is much more 
durable. Brazil wood is fcarcely ufed, except as an 
auxiliary; becaufe tire colour which it imparts to wool 
is not permanent. See further, on dying fubftances, in 
the article Chemistry, vol. iv. p. 343, &c. 
Wool is dyed crimfon, by firfl impregnating it with 
alumina, by means of an alum bath, and then boiling it 
in a decodtion of cochineal till it has acquired the wifhed- 
for colour. The crimfon will be finer, if the tin mor¬ 
dant be fubflituted for alum : indeed it is ufual with 
dyers to add a little nitro-muriat of tin when they want 
fine crimfons. The addition of archil and potafli to the 
cochineal, both renders the crimfon darker, and gives it 
more bloom; but the bloom very foon vanifhes. For 
paler crimfons, one-half of the cochineal is withdrawn, 
and madder fubflituted in its place. Wool may be dyed 
fcarlet, the molt fplendid of all colours, by firfl; boiling 
it in a folution of murio-fulphat of tin ; then dying it 
pale yellow with quercitron bark, and afterwards crimfon 
with cochineal : for fcarlet is a compound colour, con¬ 
fiding of crimfon mixed with a little yellow. This 
method was fuggefted by Dr. Bancroft, who firfl ex¬ 
plained the nature of the common method. The pro¬ 
portions which, lie gives are eight parts of murio-fulphat 
of tin for one hundred parts of cloth. After the cloth 
has been boiled in this folution for a quarter of an hour, 
it is to be taken out, and about four parts of cochineal* 
and two and a half parts of quercitron bark, are to be 
thrown into the bath. After thefe are well mixed, the 
cloth is to be returned again to the bath, and boiled' in 
it, till it has acquired the proper colour. 
The common procefs for dying fcarlet is as follows: 
Twelve parts of tartar are dilfolved in warm water; 
then one part of cochineal is added, and foon after ten 
parts of nitro-muriat of tin. When the bath boils, one 
hundred parts of cloth are put in, turned brifldy through 
the bath, boiled in it for two hours ; then taken cut, 
aired, waffled, and dried. Into another, batli eleven 
parts of cochineal are put; and after its colouring matter 
is fufficiently extracted, twenty-eight parts of nitro- 
muriat of tin are added. In this bath the cloth is boiled 
for an hour, and then waffled and dried. Every pre¬ 
ceding writer on dying took it for granted, that the 
yellow tinge necelfary for fcarlet was produced by the 
nitro-muriat of tin, or rather by the nitric acid of that 
compound, and that the tartar was only ufeful in en¬ 
livening the colour. But Dr. Bancroft afeertained, by 
aftual experiment, that nitro-muriat of tin has no fuch 
effect ; that cloth, impregnated with this or any other 
tin mordant, and afterwards dyed with cochineal, ac¬ 
quires only a crimfon colour, unlefs tartar be added; 
that the tartar has the property of converting part of the 
cochineal to yellow ; and therefore is the real agent in 
producing the fcarlet colour. Good fcarlet, indeed, 
cannot be made without tin; becaufe every other 
mordant fullies the colour, and renders it dull. 
Or BLACK. 
The fubflances employed to give a black colour to 
woollen cloth, are red oxyd of iron and tan. Thefe two 
fubftances have a ftrong affinity for each other; and 
when combined, affume a deep black colour, not liable 
to be deftroyed by the a6tion of air and light. Logwood 
is ufually employed as an auxiliary, becaufe it com¬ 
municates luftre, and adds confiderably to the fulnefs 
of the black. It is the wood of the tree called by 
Linmeus htemaloxylum campechianum, which is a native of 
feveral of the Welt India iflands, and of that part of 
Mexico which furrounds the Bay of Honduras. It yields 
its colouring matter to water. The decoition is at firfl 
a fine red bordering on violet, but if left to itfelf it 
gradually affumes a black colour. Acids give it a deep 
red colour ; alkalies a deep violet, inclining to brown. 
Sulphat of iron renders it as black as ink, and occafions 
a precipitate of the fame colour. The precipitate pro¬ 
duced by alum is dark red ; the fupernatent liquid 
becomes yellowifli red. 
Cloth, before it receive a black colour, is ufually 
dyed blue. This renders the colour much fuller and 
finer than it otherwife would be. It the cloth be coarfe, 
the blue dye may be too expenfive ; in that cafe a brown 
colour is firfl given by means of walnut peels. Wool is 
dyed black by the following procefs. It is boiled for 
two 
