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time pi:mpiiig your ley i;o to the boiler from the refervoir, into 

 vvhicli it Hills from the cloth, and returning it bciling hot 

 upon tlie clolh, lb that the hot ley may aft powerfully and 

 equally upon every part thereof. 



After each bucking your cloth mud be laid upon the 

 grafs in the blcach-ficld for fome days. The bucking, and 

 expofure on the ground, mud be repeated about ten times 

 fucceffively, according to the nature of your cloth ; it (liould 

 then be dried up, fourtd, and wafhed well in clean water ; 

 if the water is rather warm, the better. 



Your two firit buckings ought to be from a (Irongcauftic 

 ley of pot-afhes ; but afterwards you (liould abate of that 

 fireiigth, left it (liould injure your cloth. Mild ley, or pearl- 

 a(h, (liould be ufod for the latter buckings, as the cloth 

 becomes nearer white. 



This was the management during the fummer months ; 

 but for four months in winter bleaching \v:;s fulpended, the 

 operations being periodically interrupted, and the capital of 

 the manufafturers or proprietors of the goods locked up. 

 Even during the bleaching months, their property was long in 

 preparing for fale ; as cotton goods, which required from 

 four to fix applications or repetitions of alkaline leys, con- 

 lumed fo many weeks in bleaching, whilll linens, which 

 could not be bleached by Icfs than from twelve to twenty 

 applications, could not be brought in a marketable (late to 

 the proprietor hardly in fix months. 



Such was the (late of bleaching till Mr. Scheele, a Swede 

 and eminent chemift, difcovered tlic properties of oxygenated 

 muriatic acid, procured by mixing manganefe with marine 

 acid, in rendering vegetable matter white ; and M. Berthol- 

 let, the celebrated French chemift, improved tliis operation, 

 and aftually applied its powers in bleaching cotton goods by 

 interpoiiiig its aftion between the different alkaline opera- 

 tions inftead of the tedious expofure of the goods to an un- 

 certain atmofphere ; the fame effeft being produced by im- 

 merfion of the cloth in this acid, as by laying the goods 

 upon the grafs in the bleach-field, expofed to air and 

 light. 



Difcovery of and Sanations in the Mode of procuring the 

 Oxygenated Muriatic Acid. 



By the addition of vitriolic acid to common fait, an elaf- 

 tic aeriform fluid, or muriatic gas, is difengaged, from 

 which with water a marine acid is produced. The mineral 

 fubftance manganefe, or what the modern chemifts call oxyd 

 of manganefe, contains what was formerly denominated 

 vital air, pure air, or dephlogiftlcated air, but now named 

 oxygen. Manganefe yields oxygen, when marine acid is 

 added to it, and fubmitted to diftillation ; the liquor pro- 

 duced by the contaft of this oxygen with water, is the oxy- 

 genated marine or muriatic acid difcovered by Mr. Schtele, 

 about the year 1774, when he obferved and applied its ef- 

 fects in rendering eolourlefs vegetable fubilances of various 

 kinds, more as a matter of curiofity than ufe. 



M. BerthoUet, in the year 1786, improved the procefs of 

 its preparation, applied its power to bleaching or deftroying 

 the vegetable colours natural to cloth, the refult of which 

 experiments he gave to the world in the year 1789 ; but, 

 without derogating from the merit of this excellent che- 

 mift, it is juliice to Hate, that, previous to any publica- 

 tion by M. BerthoUet, Mr, Scheele communicated to 

 Mr. Kirwan the properties of the dephlogiftlcated marine 

 acid in whitening vegetable fubftances, and Mr. Kirwan, 

 then refidiiig in Newman-Street, London, fuggefted to Mr. 

 C. Taylor, the prefent fecretary to the Society of Arts, &c. 

 the probalDilitv of its ufe in bleaching ; and a whole piece of 

 callico, in the ttale received from the loom, was, in the Ipring 

 of i/iiS, adualiy bleached white, printed in permaneut co- 



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lours, and produced in theManchefter market ready for fale, 

 having undergone all iheie operations in lefs than 48 hours, 

 by the joint efforts of Mr. Cooper, Mr. Baker, and Mr. 

 Tsylor, which is perhaps the firft entire piece, either in 

 France or England, that fully afcertained the real merits of 

 the new mode of bleaching, and a certainty that it might be 

 generally ufeful in commerce. This experiment was imme- 

 diately followed by the eftablifhment of a large bleaching 

 concern by Mr. Cooper, Mr. Baker, and Mr. Horridge, at 

 Raikes, near Bolton, in Lancaftiire, and before any confi- 

 derablc bleac'-iing work was aftually at work in France. 



The ingenous Mr. Watt we believe to be the firil perfon 

 who fimplified the procefs of preparing the oxygenated mu- 

 riatic acid, by means of a mixture of common fait and man- 

 ganefe, previous to the addition of the vitriolic acid. Soon 

 afterwards the operations of the bleacher were farther facih- 

 tated by the fubftitution of large and commodious ftills of 

 lead, inftead of glafs veffels, and both thefe improvements 

 have fince been in general ufe. 



We (hall now proceed to mark the various treatment of 

 the oxygenated muriatic acid when obtained, and the differ- 

 ent means which have been adapted to fit it for application 

 in bleaching. 



It having been found in the earlier ftages of diftillation, 

 that common marine acid was produced inltead of the de- 

 phiogifticated or oxygenated muriatic acid ; and from the 

 violence of the ebullition, that manganefe itfelf was fome- 

 times thrown over from the ilill, M. BerthoUet had recourfe 

 to an intermediate velfel, containing water, to abforb the ma- 

 rine acid gas, and ftop other impurities which might conta- 

 minate the oxygenated muriatic gas in its paffage through 

 this veffcl to the receiver. 



It will here be neceffary to difcriminate the various modes 

 in which the oxygenated muriatic gas has been treated, after 

 pafling the intermediate veffel laft mentioned. 



Mr. Scheele feems generally to have operated with the acid 

 in the ftate of gas ; but M. BerthoUet fought to condenfe it 

 in water, with which he filled his receiver, or wooden veffel, 

 and which water he kept agitated during the diftillation, to 

 accelerate the folution or combination of the gas. 



The oxygenated muriatic acid, tiius prepared, was drawn 

 from the receiver into kiers, or large wooden veffels, where 

 its ftrengch was regulated by the addition of water ; after 

 which, the goods to be bleached were immerfed therein 

 from fix to twelve hours, but moft frequently during the 

 night ; and though thefe periods may feem fhoit, they were 

 fufficient to allow the cloth to become more white than 

 could be done by as many days' expofure to the atmofphere 

 and a fummer's fun, and were then ready for a frefh appli- 

 cation of the alkahne leys. 



Such was the bleaching liquor of M. BerthoUet ; but it 

 was found in praftice yet defeftive, as the volatility of the 

 gas occafioned its fpeedy feparation from the aqueous folu- 

 tion ; a decompofition even by light alone in glafs veffels 

 took place ; a rapid lofs in the ftrength of the liquor when 

 expofed; and much danger to the health of the workmen 

 from its fuffocating quality ; at the fame time, that in ex- 

 trafting the natural colours of the cloth, it alfo tended to 

 difcharge the colours dyed in the yarn, and were along with 

 the gray cotton an imperfeftion which precluded its ufe in 

 an infinite variety of Britifh manufaftures. 



Similar circumftances probably led fome bleachers refident 

 at Javelle, in France, to add a folution of cauftic alkali to 

 the water in the receiver, and by this means to remedy 

 many of the defefts complained of. 



But M. BerthoUet continued to recommend his procefs, 

 eonfidering fuch fubftance as impairing the bleachiag powers ; 



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