An BJJliy on Bleaching, 3 1 r 



To bleach cloth, it mufl he immerfed in the fame manner 

 in a flight alkalino-cauftic folution marking two degrees by 

 the areometer. I here fuppofe that the cloth has been fub- 

 jccted to the neceffarv preparations to free it from the drefs- 

 ing, according to the inltruftions I gave when fpeaking of 

 flax and hemp. ♦ 



While the cloth is immerfed, and impregnating itfelf with 

 the alkaline liquor, the boiler is filled to the height of a foot 

 with a ley of equal ftrength. This may be done by means 

 of a bent leaden funnel ; but the door is large enough to pour 

 it in, by taking it up from the tub with buckets : the work- 

 man then enters the apparatus, and fixes the end of a piece 

 of cloth, with packthread, to one of the arms of the furtheft 

 reel A, fiV. 1. , Plate V.) while another workman without 

 turns it tifl the whole piece is rolled up: he then fixes a fe- 

 cond piece, tacking it to the former, if this operation has not 

 been done before ; then rolls it up, and continues in this 

 manner till eighteen or twenty pieces are rolled up. He then 

 throws the extremity of the lait piece which remains over 

 the roller B, near the arch ;, conveys it under the two lower 

 rollers C,D, in the copper EEE; then makes it pafs over 

 tiie other roller F, placed near the arch of the apparatus; 

 and at laft fixes it to one of the arms of the reel G. The 

 workman afcertains the height of the liquor in the infide by 

 means of the regulator II, and immediately fhuts the cock ; 

 after which he furrounds the door K with old rags or tow, 

 and fixes it ftrongly in its place by fcrews, which ferve to 

 check and prevent the efcape of the fteam. The fire being 

 kindled, and the heat increafed to that of boiling water, the 

 workman winds up the cloth, beginning with that reel which 

 was empty, until it is entirely charged with it; he then 

 lowers the cranks of the rollers C,D, to immerfe the cloth 

 in the boiling liquor, fpeedily winds it off, rolling it up on 

 the reel which has been emptied, unhooks the lower rollers, 

 and winds back the cloth in another direction without im- 

 merfing it in the liquor. At the end of two hours, more 

 or lefs according to the finenefs of the fluffs,- the alkali car- 

 ried up by the caloric will have completely penetrated the 

 fibres of the cloth, fuelled by the extraordinary heat of the 

 fteam. The fire is then flackened ; and when the apparatus 

 is fufficiently cold the door is opened, and preparation is 

 made for immerfing the cloth in the oxygenated muriate of 

 lime *. Care mull be taken, in order to fhorten the mani- 

 pulation, to charge in the laft winding the reel near the door : 



* Tiie cloth ought not to be immerfed till after it has been waflied. — 1 

 Note of Chm >ta(. 



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