Page:Encyclopædia Britannica, first edition - Volume I, A-B.pdf/671

 56$: B L E A C KING. coarfe has dreeped pn racks made for the purpofe, it is To accompliffi this end, the cloth is laid to deep in blood-warm water. A fmaller degree of heat would not boiled, making the lye ftrong in proportion to the water diffolve the dreflxng fo foon ; and the greater might c6in the cloth. The common method of fouring coarfe linen is, to agulate and fix, in the body of the linen, thofe particles mix fome warm water and bran in the vat, then put a which we defign to carry off. In a few hours the dref* layer of cloth, then more bran, water, and cLth ; and fing made ufe in weaving is diffolved, mixed with the fo on, till the cave is full. The whole is tramped with water; and, as it had acquired fome degree of acidity, mens feet, and fixed as in the former procefs. A thou- before application, it becomes a fpecies of ferment. Each fand yards of cloth, yard-broad, require betwixt four ferment promotes its own particular fpecies of fermentand fix pecks of bran. The cloth generally lies about ation, or inteftine motion; the putrid ferment lets in three nights and two days in the four. Others prepare motion the putrefadlive fermentation ; the vinous ferment their four twenty-four hours before, by mixing the bran gives rife to the vinous fermentation; and the acid ferwith warm water in a feparate vefiel; and before pouring ment to the acetous fermentation. That there is a real it on the cloth, they dilute it with a fufficient quantity fermentation going on in fteeping, one muff be foon conof water. After the cloth is taken from the four, it vinced, who attends to the air-bubbles which immediateought to be well walked and rinfed again. It Is then ly begin to arife, to the feum which gathers on the furgiven to men to be well foaped on a table, and after- face,' and to the inteftine motion and fwelling of thewards rubbed betwixt the rubbing-boards. When it whole liquor. That it muft be the acetous fermentation,. comes from them, it Ihould be well milled, and warm appears from this, that the vegetable particles, already water poured on it all the time, if conveniency will al- in part foured, muft firft undergo this procefs. low of it. Two or three of thefe rubbings are fufficient, The effetfl of all fermentations is to fet the liquor in motion ; to raife in it a degree of heat; and to emit airand the cloth very feldom requires more. The lye, after the fouring begins, is decreafed in bubbles, which, by carrying up fome of the light oleagiftrength by degrees ; and three boilings after that are nous particles along with them, produce a feum. But commonly fufficient to finiffi the cloth. Afterwards it is as the dreffmg is in fmall quantity in proportion to the Hatched, blued, dried, and bittled in a machine made water, thefe effects are gentle and flow, The acid falts for that purpofe, which fupplies the place of a calendar, are no fooner feparated, by the acetous fermentation,, from the abforbent earth, which made them not percepand is preferred by many to it. This method qfed in the bleaching of our coarfe cloths, tible to the tongue in their former ftate, than they are is very like that pradtifed in Ireland for both fine and united to the oily particles of the tallow, which likewife coarfe. The only material difference is, that there the adhere fuperficially, diffolve them, and render them, in bleachers ufe no other affies but the kelp or caffiub. A fome degree, miffible with water. In this ftate they are lye is drawn from the former by cold water, which dif- foon waflted off by the inteftine motion of the liquor. folves the falts, and not the fulphureous particles of the The confequenee of this operation is, that the clothkelp affies. This lye is ufed till the cloth is half whi- comes out freed in a great meafure from its fuperficial tened, and then they lay afide the kelp-lye for one made dirt; and more pliant and foft than what it was. • Whenever this inteftine motion is pretty much abated,. of caffiub affies. In the preceding hiflory of bleaching we may obferve, and before the feum fubfides, bleachers take out their that it naturally divides itfelf into feveral different cloth. The feum, when no more air-bubbles rife to fupport branches or parts, all tending to give linen the degree -it, Teparates, and falls down ; and would again commuof whitenefs required. How they effe&uate that comes nicate to the cloth great part of the filth. But a longer next to be confidered. ftay would be attended with a much greater difadvantage. The general procefs of bleaching divides itfelf in- The putrid follows clofe upon the acetous fermentation: to thefe different parts. i. Steeping and milling. 2. When the latter ends, the former begins. Were this to Bucking and boiling. 3.-Alternate watering and drying. take place, in any cqnfiderable degree, it would render 4. Souring. 5. Rubbing with foap and warm u'ater, the cloth black and tender. Bleachers cannot be too carer Itarching, and bluing. We ffiall treat of thefe different ful in this article;. parts in their order. The firft queftion that arifes to be determined on thefe • principles is, .What is the propereft liquor for fteeping , cloth ? Thofe ufed by bleachers are plain water; whiteSTEEPING, water, equal parts; and rye-meal or bran Green linen, in the different changes which it has linen lyewithandwater. They always make ufe of lye when, undergone before it arrives at that Hate, contrails a mixed they have it. . great foulnefs, This is chiefly communicated to it by After fteeping, the cloth is carried to the putftockthe dreffing compofed of tallow and fowen, which is a to be freed of all its loofe foulnefs. There can be kind of flummery made of bran, flour, or oat-meal mill, nothing contrived fo effedlual to anfwer the purpofe as feeds. The firft thing to be done in the bleachfield is to this mill. Its motion is eafy, regular, and fafe. While take off all that filth which is foreign to the flax, would preffes .gently, it turns the cloth; which is continually blunt the future adlion of the falts, and might, in unlkil- itwaflted with a ftream of water. Care muft be taken that ful hands, be fixed in the cloth. This is the defign of no water be detained in the folds of the linen, otherwife fteeping. that part may be damaged. BUCKING