American watchman and Delaware advertiser. [volume] (Wilmington, Del.) 1822-1828, 1822-11-15
FROM THE NEW YORK STATESMAN.
on TIE WrO.qD Plant AND W0AD VAT

U.F TIE WO.9D PL.f.N'I .f.fD ~ OHD Fai
"The isalis tinc,oria, or woad plant, has been
used for nearly TWO thousand years, in dying OF blue
and was the only material from which the Europe
obtained that color before the discovery OF South
America, from whence indigo was first obtained.
The French, during the late war, being depri-
we'd OF their usual supply Of indigo from the eastern
and western continents, caused the isatis 10 be cul
tivated for the purpose Of obtaining indigo from it,
and succeeded in the attempt. This plant is still
used the basis Of the blue vat for dying Of wool
len, because the materia tincloria has never fur
nished any material that can We admitted IS sub
slilute. 1t is plant which combined with indigo
gives the best and most permanent blue dye hitherto
The woad plant requires deep, rich, oomy soil, &
lis value when manufactured, is Away in proportion
10 the quality OF the land which has been rased
that which has been grown weak poor land. is Of no
more value than so much b an s madden; that which
comes from land Of middng quality may be used oc-
casonay to yamp with, but when used altogether by
itself the colours will be weak in body, will they
stand the usual test OF acids and exposure to The
atmosphere. Woad that has been raised on good
land, gathe ed in proper season. and sktul,y aten
ded during the manufacturing afterwards, will, in
the hands OF good workman, make colours highly
beautiful and very permanent but its property, as
might be expected tIom he contingencies TO which
q is subject is very variable, and from hence arises
all the difficulties which the dyer has 10 encounter,
and the consequent disappointment experienced by
the manufacturers Of this country in the skill Of
European woad dyers.
10 obtain prime Article Of this kind, invariably
the same in strength and quality, must be therefore,
"a grand deslderatum with our dyers and manu!ac
turers 10 effect this OBJ ect, have lately imported
a small quantity Of woad, now for sale at Nlessrs.
DIVE Bethune & Co which is the best that the west
OF England Affords and il encouraged, shall con-
nue 10 supply the market at reasonable price.
until can find some respectable landholder in the
vicinity OF New York, who has ground Of the quail
ny wanting, and sufficient enterprise 10 undertake
the raising and manufacturing of it in regular and
permanent way.
The woad vat is compounded OF woad, indigo,
vegetable ferments, and Of a caustic or sub.carbo
ma ed alkall the woad acts both as colourng and
Preventative matter There is adiflculty attending
the use OF this material arising from its liability to
run into the puttefactye fermentation whenever
ms happens, the vat is inevitably lost, and it re.
CURES considerable practical skill prevent il. The
vegetable ferments are usually bran and madden,
out the moterials which may be used are very nu-
mefous, and every ignorant workman considers thai
ne : " possession Of an important secret, WHEN he
has substituted some other ferment in place OF those
nave known we'd. malt maltdust beer grounds
yeast disiiilers swill and many Others applied and
as ali VI Them are vegetable iermenis, they must
? oduce Ike effect when used with julgmert, -
he indigo is 6 ound to paste, and put into the
va together with the woad bran, and madden; when
the whor has termented until the indigo is reduced
70 rs mlniolum Of oxidation, which may be known
oy the h4uol being OF green color, bearing rich
purple beds. and having copper scales on its sur
face, as much of lime is gradually added as will
hold the indigo IN solution. Ii will be necessary 10
replensn, as soon as given portion OF the alkaline
earth becomes satura ed with catbonc acid gas BY
adding an additional quantity OF lime. and when ne
cessary ct vegetable ierments and indigo A good
wo KHAN may keep one Of these watts in daily ope-
ration Tor SIX, nine or even twelve months without
any njuryto the colour 1t is this continuity to-
geher with the small quantity OF erments used, and
the great beauty and durability OF the colour, which
give o the woad vat SO decided superiority over
every other.
The progress lately made in chemical science
has enabled several writer's to give partial theory
OF the operations of the blue vat Doctor Bancroft
informs Us, that the indigo is de-oxdated during
the fermentation, and broehI back to green state,
and hat the alka is used as solvent for the nd-
go:' but | you'd beg leave to suggest that the
akaii produces another, and in my opinion, very
important effect, in combining with The carbonic
acid gas.
Ills well known to every scientific workman that
The effect produced by the lime is always in an ex
act ratio with its causticy and that the portion
which wat requires does not depend so much onI
the quantity Of indigo used as it does, on the pro.
portion of the vegetable ferments and it is always
observable that the slkali and lerments are uni
ioEmly successful in given proportions, making due
allowance for the causticy Of the former.
The rationale OF this complicated operation, has
never been, and probably never will be satisfactorily
explained. 1t is certain, however, that the indigo S
partially de-oxded as stated by most theoretical,
writer's on the SUBJECT; bu, do not consider il as
equally certain that the akali acts merely as SOL
vent OF the dgo. 1t appears that carbonic and
oxygen gasses are copously liberated during the
fern en- alton. that lhese cnnhln. In nnsc.r1 49,