COTTON MANUFACTURE.

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liquor should become cold, it must be made once more as hot as the hand can bear. Aportion of it is now transferred into another vessel, called a back, in which the cotton isworked till it be well penetrated with the decoction. It is then taken out, wrung at thePeg or squeezed in a press, and straightway hung up in the drying-house. Some more°* the fresh decoction being added to the partially exhausted liquor in the back, the proCe ~' s resumed upon fresh goods.

fhe manipulation is the same with sumach, but the bath is somewhat differently made;because the quantity of sumach must be double that of galls, and must be merely infusedtn very hot water, without boiling. When galls and sumach are both prescribed, theirbaths should be separately made and mixed together.

2- Jlhiming. Alum is a salt which serves to prepare cotton for receiving an indefinitevariety of dyes. Its bath is made as follows : For 100 pounds of scoured cotton, abouta0 gallons of water, being put into the copper, are heated to about 122° F., when 4 ounces°‘ alum, coarsely pounded, are thrown in for every pound of cotton, and instantly dis-solved. Whenever the heat of the bath has fallen to about 98° F., the cotton is wellWorked in it, in order that the solution may thoroughly penetrate all its pores. It is thenaken out, wrung at the peg or squeezed in the press, and dried in the shade. The solu-t°n of alum is of such constant employment in this kind of dyeing, that it should be*ade in large quantities at a time, kept in the alum tun, where it can suffer nodeteriora-l °n, and drawn off by a spigot or stop cock as wanted.

■‘here are certain colors which require alum to be deprived of a portion of its acid ex-aess > as a supersalt; which may be done by putting 1 ounce of crystals of soda into theu n for every pound of alum. But so much soda should never be used as to cause anyj’(’ r maneiit precipitation of alumina. When thus prepared, it is called saturated alum,

°agh it i s by no means neutral to litmus paper: but it crystallizes differently from ordi-na |7alum.

t.otton does not take up at the first aluming a sufficient quantity of alum; but it mustdri 6 j Ve a sec ond, or even a third immersiofi. In every case the stuff should be thoroughlyl el ft with an interval of one or two days between each application; and it may even bethe ,0r or ^ hours moist with the alum bath before being hung in the air. WhenCotton is finally dry, it must be Washed before being plunged into the dye bath j other-n a ,, e > the portion of alum not intimately combined with the cotton, but adhering exter-hv ,r l ° ' ts filaments, would come off by the heat, mix with the bath, alter the colorto ., ISS °lving in it, and throw it down to the bottom of the copper, in the form of a lake,Uibr \ ? re *t loss of the dyer. Madder reds, weld yellows, and some other colors arean( j e hcilliant and faster when acetate of alumina, prepared with acetate of lead, alum,and 3 ■ potash, is used, than even saturated alum. This mordant is employed cold,

3 a ‘ 4 ° Banme.

4 ~* 0r daTits, See this article in its alphabetical place.

are distinguished info two classes; the coloring bath, and the dyeing bath.l ‘Xc e .,r r " U ' r ser V es 1° extract the coloring matters of the different substances with thesio n P 10 j ° y ma( 14er, which is always used in substance, and never as an extract, infu-bath iT “ ecoct l°n. In all these cases, when the color is extracted, that is wnen the dyeconi a C0In Pleted by the degree of heat suited to each substance, it is then allowed tofor t! ; 0Wn r .

10CP aaiiof

tint 1 * certa iu way, and the cotton is worked or winced through if, io get the wished-~1' a a ^fi' s is what is called the dye bath. Several coloring batns are made in the100°’ to f serve to dye-also in the cold; but the greater part require a heat of 90° orof the r a<a **tate the penetration of the stuffs by the coloring particles. The description5. Oy «| ra * < ^- e Baths is given under the individual dyes,eeiveq'th a was ^ n S after the dyeing .—The washing of the cottons after they have re-fully _ - e “yes, is one of the most important operations in the business. If it is not care-it touc hes ° rm ~d> the excess of color not combined with the fibres is apt to stain whateveroff the ct l* ^ a ' s '"convenience would be of little consequence, if the friction carriedPears motf < i r a :qUally ^ rom *B the P°> nts j But it does not do so, and hence the surface ap-Watcr flow » ^ well-planned dye house should be an oblong gallery, with a stream of

mng e( j a along m an open conduit in the middle line, a series of dash-wheels ar-Winces or re* 1 ? 1 ***e_wall, at one side, and of dyeing coppers, furnished with self-actinghand, by th • a ? a ' nst the other. In such a gallery, the washing may be done either bvor by the dash-wheel, according to the quality of the dye,* n d pin 5 by 6 0 the stuffs. And they may be stripped of the water either by the jack??Uses on each s ?, ueez ' n ° roller, or by the press. Wooden pins are placed in some dye, l §h, 3i i nc i. ? j.°f tlle wash cistern or pool. They are somewhat conical, 1J foot<? v el of about a diameter at the base, 1J at the top, are fixed firmly upright, and at a® R Azri.-won lee v a ° 0Ve tIle Bottom of the cistern, so as to be handy for the workmen.

** N > Calico o'’ a USTIC > Madder, Black Dye, Brown Dye, &c., as also Bleaching,C °TTON M 4 I J'™ , :’„5 ut,GIti o, Dyeing, Ac. ..

™ B FACTURE. (Filature . de Cotan, Fr.; Baumutollenspinntrie ,