loa An TLffay on Bit aching. 



For bleaching woollen fluffs we propofe the following 

 method \ — The fluffs are firft to be fcoured by a (lightly 

 alkaline lev in the proportion of a pound of potato to 50 

 pounds of wool; the ley mull he heated to the temperature 

 of 30 degrees: the old procefs, by means of ftale urine, al- 

 ready mentioned, may he alio employed. Urine is preferred, 

 becaufe it holds in folution onlv a fmall quantity of fait in- 

 capable of hurting the wool. When the greafe is difiblved, 

 and the wool has been perfectly rinfed, it is to be wafhed in 

 warm foapy water: this part of the fcourmg procefs is per- 

 formed fomctimes in the fulling mill, fometimes with beat- 

 ers, and fometimes by treading in the tub. In all thefe cafes 

 the fluffs rmi ft he freed from greafe by repeated wafliings be- 

 fore they are fulphured. If a very bright whitenefs be re- 

 quired, it will he proper to expofe them to heat a feeond, 

 and even a third time, alwavs in water a little foapy, made 

 with two ounces of that fubftanee for each pound of wool. 

 It will be better to repeat this operation, turning the fluff for 

 half an hour at each immerfion with a flick, than to run the 

 riilc, by too (Irong a ley, of injuring the quality of the wool. 

 After the fluff has been carefully rinfed it is carried to the 

 tubs to be immerfed in liquid fulphurous acid, or fulphur 

 water, as the workmen term it: the pieces are rolled upon 

 the reels, and are drawn through the fulphurous acid by turn- 

 ing them untii it is obferved that the whitenefs is fufficiently 

 bright. They are then taken out, and left to drain on a bench 

 covered with cloth, left they mould be ftained in confequence- 

 of the decompofition of the wood by the fulphurous acid : they 

 are next waflied in river water, and Spanito white is employed 

 if it toould be judged neceffary. This operation is performed 

 by pafling the pieces through a tub of clear water in which 

 about eight pounds of Spanito white have been diluted. To 

 obtain a fine whitenefs, the fluffs, in general, are twice ful- 

 phured. According to our procefs, one immei (ion and reel- 

 ing for two or three hours is fufiicient. Azuring or blueing 

 is performed by throwing into the Spanito-white liquor a 

 folu ion of one part of Pruffian blue to four hundred parts of 

 water, (baking the cloth in the liquid and reeling it rapidly. 



The operation is terminated by a flight watoing with foap, 

 to give fofmefs and pliability to the fluffs. The final opera- 

 tions of drving, flretching, pre fling, &c. are foreign to the, 

 proceffes which are the object of this eflay, 



Before venturing thus to recommend the ufe of the liquu] 

 fulphurous acid, we made a great many experiments on fpun 

 wool and woollen fluffs^ and always with the moil complete 

 fuccefs. 



0/ 



