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Ute roller B, the moveable frame F being drawn forwaid by 

 the cloth ; for as the cloth is lapped on the roller B, the frame 

 F is drawn towards it betwixt the uprights LL, and by 

 means of a projeiSing wood forming an inchned plane fixed at 

 M, on each fide, near the top of the frame F, the rails O are 

 raifcd ott" the pegs NN, and carried forward on the part M 

 of the frame F, without impeding its progrefs to the tm 

 roller B, till the wrapper G, to which the cloth is faftened, 

 pafics over the roller, and the wire at G, which attaches it to 

 the cloth, is withdrawn, leaving the whole of the cloth to be 

 dried on the tin roller B, which roller is then taken out and 

 placed in the drying frame. 



To afcertain the llrength of the oxygenated munatic acid 

 ufed by the bleachers in France, Monf. Dcferoizilles made 

 tife of a folution of indigo in the vitriolic acid, for which pi;r- 

 tjofs he takes one part of finely pulverized Guatemala indigo, 

 and eight parts of concentrated vitriohc acid, whicli mixture 

 fhould be put in a glafs veffel, and kept of a gentle heat by 

 Handing near the fire or in warm water all night, and repeat- 

 edly ftirred with a glafs rod or tube. When the folution is 

 complete, it is diluted with a tlionfand parts of v.-nter. One 

 meafure of this fohition is put into a graduated tube of glafs, 

 and oxygenated liquor is added, until the colour of the 

 indigo is completely deftroyed, and the ftrength of the 

 oxygerated liquor is afcertaincd by its power in difcharging 

 the colour. 



Mr. Rofe has recommended a method which is better 

 adapted for general ufe ; which is, " to have fmallmeafurcs 

 properly proportioned to each other, and when the liquid is 

 itrong, to prevent wafte of the indigo liquor prepared as 

 above, and a tedious repetition of meafures, let a fniall mea- 

 fure of the liquor to be tried be put into a meafure containing 

 24 of the fame meafures of water (it then becomes dihited to a 

 twenty-fifth part) ; to a meafure of this diluted hquor add as 

 ■many meafures of the blue left as it will difcharge, which mul- 

 tiplied by 2 ■;, gives its whole ftrenglh. It will be proper to 

 have a meafure of five for the fake of difpatch, in adding the 

 bine tell liquor. It is neceflary that the experimenter 

 fliould fit low enough to view his meafui-es horizontally, in 

 order that they may not be overfilled, otherwife he may be 

 deceived. 



Great care fliould be taken in the choice of the indigo and 

 the vitriolic acid employed, for unlefs the indigo is of the Gna- 

 tim:ila kind, or bell Eall India, and the vitriolic acid highly 

 concentrated and pure, the colour produced will be a greenifii 

 brown, inilead of a bright blue. 



Mr. Chaptal has employed tire oxygenated muriatic acixl 

 to the purpofc of bleacliing paper, both by applying it to the 

 rags before worked dov.m, and to the pulp or patte j he alfo 

 reftored the white to prints difcoloured by time, by im- 

 merfing them in the oxygenated muriatic acid liquor, or ex- 

 pofing them to the aftion of its vapour. And Icveral pa- 

 tents have been granted in this kingdom for bleaching pulp 

 or paper, amongil which Mcflrs. Clement and George Tay- 

 lor, of Maidftone, in Kent, have obtained one for bleaching 

 the pulp, by inclofing it with a liquor of oxygenated muriate 

 of pot-afli, in a vcil'tl refLinbling a churn, eight feet diameter 

 at the great end, three feet four inches diameter at the little 

 end, and two feet ten inches in the clear. This veflel revolves 

 upon an axis at each end, and the pulp, by this motion, and 

 projefting parts within the veflll, is conilantly expofing frerti 

 lurfaces to the liquor, till the whole pulp is fufficientiy 

 whitened. 



Mr. Bigg, of Iping, in Suifex, has fince obtained a patent 

 ■for bleaching paper, and rcftoring to whitcnefs damaged or 

 mildewed paper, by expofing in clofe wooden veffels paper, 

 in quantities of ft;; or eight Sieets together, on wooden frames 



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placed at fmall diftances from each other, to the a£llon of 



oxygenated muriatic gas, and after the paper is taken out, 

 preflcd, and dried, previous to its being fizcd, wetting it in a 

 folution of alum water. 



Another method he propofes, is by wetting and foakinf 

 the paper in oxygenated muriatic acid liquor, till it is pro- 

 perly bleached ; after which it fliould be well prefl'ed and 

 dried, and wet out in the alum water, as in the other pro. 

 cefs. 



A patent has likewife been granted to Mr. Ellas Carpenter, 

 of Bermondfey, London, for a method of bleaching paper 

 in the water leaf or (hcet, and fizing it without drjnng ; he 

 ufes for this purpofe a llout deal box or cafe, which muft be 

 carefully clofed, and capable of confining water or fteam 

 within thif. The paper to be bleached is to be hung on 

 ilripsof glafs, about 15 inches long, placed in grooves within 

 the box^ about four fheets on each ttrip ; the paper is taken 

 for this purpofe when preffcd in the packs in its wet {late, and 

 when the box is filled and clofed, it is expofed to the adlion of 

 oxygenated muriatic gas for eight or ten hours, and when 

 fufficientiy bleached, fized with a prep.-nation made from 

 one hundred weight of pieces of flcins boiled in water and 

 flrained, then fourteen pounds of alum, feven pounds of white 

 vitriol, and one pound of gum arable addtd ; thefe ingredients 

 will niakc fize enough tor about 50 reams offoolfcap paper; 

 tlie paper when fized and prefTed, is finifhcd in the iifual way. 

 To prevent the noxious qualities of the gas to the workmen, 

 he dire&s a fohition of pot-a(h in water to be placed at the 

 bottom of the bleaching box, to abfi>rb the elallic vapours 

 which would otherwife affeft thtm on opening the box. 



Mr.Tennant of Glafa^ow, fubfcquent to the patent granted 

 him for his bleaching liquid, has obtained a patent for pre- 

 paring the oxygenated muriate of lime in a dry form, by 

 which means blecchers may be cheaply and conveniently 

 fupplied v\'ith it by him, and fave much of the trouble, ex- 

 pence, and hazard which attend the preparation of the former 

 bleaching lic^uor. 



To bleach filk from its natural gummy flate, whether in 

 fkain or manufaftured, it fhould be put into a thin linen bag, 

 and thrown into a vefhl of boiling water in which good 

 white foap lias been diifolved ; the filk fhouid boil two or 

 thvce hours in this liquor, and the bag of filk frequently 

 preffed with a ilick, and turned, fo that the gummy matter 

 may feparate from it, and nfe to the furface o^f the liquor, 

 from whence it fliould be flcimmed off, ;ind thrown away; 

 the bag fliould then be taken out, and if it contains filk goods, 

 they Ihould be well waflied in clean cold w.T.rer, to prepare 

 them for printing or dying ; but if the bag contains filk in the 

 fl'Cain, after 'it has been well wafi.ed in clean water, beaten, 

 and fiightly v.Tung, it may be put the fecond time into the 

 copper veficl, filled with cold water mixed with foap, and a 

 little indigo blue, if you wiih it tinged a little of the blueifh 

 hue. 



Trie filk, when taken out of the fecond water, fhould be 

 wrung hard with a wooden peg, to prefs out all the liquor ; 

 then fliaked, to feparate the threads ; then fufpended on 

 poles, in a clofe room or Hove wliere fulphur is burnt, which 

 improves the whitenefs of the filk. 



Woollen cloths or fluffs may be bleached and made white 

 by foap and water ; by the vapour of fulphur ; or bv chalk, 

 indigo, and fulphnric vapour. In the firfl: cafe, after the 

 fluffs have been cleaned at the fulling mill, they are again 

 worked in warmifli foap and water, to render t}iem whiter, 

 and afterwards waflied in clear water and dried ; in thia 

 ilate they are fit for dying any light colours. 



To deftroy or remove the reddifh hue arifing from boiling 

 printed cottons in madder dccodions, which prevents the 



j>riuted 



