B L E 



or palling together tbe loofe fibre! of the threads, and thus 

 allowing them to pafs more freely through the reed and 

 harnefs. To remove this fubflance, and to open the fibres 

 of the cotton, fo as to give full cffett to the fubfequent ope- 

 rations, it is proper to fteep the goods in a veifel of the 

 above form in lukewarm water, till a gentle fermentation 

 takes place, which will ufually be efiecled in 24 hours. The 

 cloth fhould then be taken out, and well wafhed in a current 

 of clear water, which will thus I'cparate a confiderable quan- 

 tity of filth without the expence of ufing alkaline leys ; and 

 the cloth is then ready to be boiled or bucked as may be 

 preferred by the bleacher. 



2d, On Boiling. 

 For boiling, a copper vcflfel is to be preferred, and the 

 goods prepared, as above mentioned, by lleeping and wadi- 

 ing, are put into the veflel containing hot water only, or 

 warm alkaline ley ; a winch is placed over the vtiTel, and the 

 piec" goods attached to the ends of each other, are, when 

 put 111 motijn by th-^ handle of the winch, dragged or rolled 

 over it till the who'e are pafled ; the winch is then turned 

 with a rerrograde motion, and the cloth gradually thus re- 

 turned back, in order that every part of each piece may be 

 thoro.'.^hly imar^ niated with the liquor, which is raifed to 

 and kept 5t a boi'ing heat, as long as it appears to extraft 

 any r.olourini: t. i-rr from the cloth; the goods are then 

 takon out a".d w<li wafhed in water. 



I'i^. I. P/afelV, fr.e-vc -; ic'iian of the boilincr pan A, of 

 copper, fet in brick-vork ii ; the wincti C, with its handle 

 D ; E, uprig Its "t wood, on which the winch turns ; F, a 

 cock to emo:%' the pan ; G, the fire-place ; H, the afh-hole. 

 1 he uU of this prccefs dfpends upon the prjperties 

 wh-ch aikahne falts have of uniting with the oily and re- 

 fi :ou6 matters whkh are either attached to or are a con- 

 ftituent part of vegetable fibres, and which contain their 

 colouring particle:, forming with them a faponaceous matter, 

 folubl? in water, and by that means eafily extricated from 

 the c;., ;h. 



3d, Or. Buciing. 

 As this is one of the moll general operations ia bleaching, 

 it wil! be necelTary to defcribe it riiore particularly. Fig. 1. 

 Plal: 1. under the word iuciiiig, Ihews at A the form of the 

 bi'ciiing tub or kier, in which the goods are to be laid ; B is 

 an iron boiler, in which the alkaline falts, as pot-afhes or 

 pearl-aflies, are to be dilTolved in boiling water ; C is the fire- 

 pb.ce, in which a fire is conflautly kept up ; D is the afh-hole; 

 E, a cock through which the boiling ley is let out upon 

 the goods ciofely placed together in the bucking tub, A. 

 A fufiicient quantity of boiling ley is let into the bucking 

 tub, till all the goods in the tub are thoroughly impregnated 

 with it ; the ley liquor is then allowed to pafs by a cock 

 at H into an iron vcfTel placed in the ground at F, and from 

 thence raifed by the pump G into the iron boiler B, and 

 thence returned hot again upon the cloth. This operation 

 is continued for fcveral hours, till the ley, by the feparation 

 of the colouring rrr.tter in the clo^h, acquires a colour almofl 

 black, a very offcnfive fmell, and nearly the confillence of 

 molafles or treacle. The cloth is then taken out, well wafhed 

 from its impu ties, and, in the old modeof bleaching, it is then 

 laid upon the ground to be whitened by expofure to the at- 

 molpiiere, but. :ri the new mode of bleaching, is fubmitted to 

 the aftiou of cl.c -jxygenated muriatic acid, to procure a fimi- 

 lar (Viiircnefs. It may be proper here to notice, that the 

 old and new methods of bleaching are yet much the fame as 

 formerly, r;.ly in the fubllitution of the ufe of the oxy- 

 genated m'.:Nrit;c acid in thofe parts of the procefs, where a 

 long expoUne to the atmofphere was formerly employed after 

 the alkaline ievs. 



B L E 



The operation of bucking afts on a fimilar principle to 

 that of boiling, but in a much more forcible manner, as a 

 greater quantity of allies is added in proportion to the 

 water made ufe of, and more heat is received and retained in 

 the large bulk of cloth placed in the bucking tub, which 

 expands the fibres of the cotton, and admits the more power- 

 ful aftion of the alkali, as is eafily dcmoiittrated by obferving 

 the very dark colour of the alkaline leys which have been 

 ufed in bucking, in comparifon with thofe which have been 

 employed in boiling goods. To thofe perfons who wifh for 

 a-'ftiil and minute account of the abforption and power of 

 heat, we recommend a perufal of count Rumford's intereft- 

 ing eflays on the fuhjecl of heat. 



The black alkaline ley which remains after bucking fhould 

 be preferved, as it will aiifwcr, after evaporating and cal- 

 cining, as her'.-after mentioned, to form again frefh alkaline 

 falts of good quality. With a view to. preferve as much 

 of the ley as polTible, it will be advifeable to wring it 

 out into a tub from the cloth or yarn, after it is bucked, 

 by the method fhewn in PLitelV. Jig. ;}. where RR are 

 two ftrong pulls, fixed firm in the ground, S T two wring, 

 ing hooks, upon which the cloth U is" twilled, to force out 

 the liquor, by vV^, a winch handle, which turns the hook 

 round on the poll R. The two hooks are kept at a proper 

 diilance from each other, one by a collar at X, the other by 

 an iron pin at Y, which runs through a hole in the fquare 

 part belonging to the hook T, which fquare has feveral holes 

 in it to bring this hook nearer to the hook S when re- 

 quired. 



4th, Souring. 

 This procefs confiils in immerfing, for the fpace of twelve 

 hours, or more, the yarn or cotton in a mixture of water and 

 fulphuric acid (vitriolic acid), well incorporated ; the proper 

 flrength of which mixture is about the acidity of lemon 

 juice, and is ufually direfted by the tafle. The four kettle 

 fhould be made o.f lead, of a form which can be heated ; the 

 heat of the hquor fhould not be greater than the hand can 

 bear with eafe. This four kettle fhould be half funk within 

 the ground, as fhewn in PLif IV. Jig. 2. where M is a fcc- 

 tion of the fouring velTel ; N, the level of the ground ; O, the 

 brickwork ; P, the fire-place, which is a half circle, or arch, 

 without any grate ; II I, a fpace filled with dry afhes, be- 

 twixt the lower part of the four vefTcl and the brick-work, 

 in order to preferve the heat of the liq'ior in that part of the 

 velTcl below the furface of the ground ; K, a brick hearth, on 

 which part of the fire is made ; L. a call iron plate, bending in 

 the formof thefourkettle, whichis intended to pi event the fire 

 placed on the floor at P K, from acting upon the lead of the 

 four vefTel ; Q, the fpace betwixt the veffel and brick-work, 

 through which the fmoke goes to the chimney. 



The conflruction of this apparatus is upon the fame prin- 

 ciple as the warm vats made ufe of by the blue dyers, the 

 intent not being to make the hquor boil, but to keep it at 

 a degree of heat which the hand can long and eafily bear. 

 There are no grate or bars ncceffary in this fire-place, as the 

 coals will bum with fufEcient rapidity without them. 



The goods may be put into this acid liquor either in a 

 wet or dry '•ftate. The befl plan is to immerfe the goods 

 in the evening in the acid hquor cold, let them remain co- 

 vered with it all night, then in the morning make a fire 

 and bring the hquor to a blood heat, in which Hate ha\ ing 

 a winch over the veffel, fimilar to that reprefented at C,fig. i. 

 give the goods a few turns over it, that every part ot them 

 may be expofed to the adiion of the liquor. The goods 

 may then be lapped round the winch to drain a little, to pre« 

 vent an unnecefTary wafle of the acid liquor, and afterwards 

 carried to the wafh-wheel, or river, to be well wafhed from 



the 



