126 * METHOD OF BL1ACHING FAPrfR. 



Laftly, if the rags be neither perfectly white nor raw and 

 unbleached, but in a medium ftate, that they are left to rot 

 for a ihorter time, for example, twelve or fourteen days, and 

 are taken up when the heat of the fermentation raifes the 

 thermometer to 30 or 35 degrees, after which the procefs is 

 to be conducted as before mentioned. 



Compofition of a hath of the bleaching liquor, for a pile of de- 

 compofed rags, weighing 50 kilograms. 

 Application and For each heap of rags a certain number, for example, 

 materials^Vthe e 'g nt or nine, wooden tubs are difpofed in a line, capable of 

 actual work. containing in the whole 600 litres of water : 450 litres of 

 pure water is poured in, and 90 litres of bleaching liquor are 

 added in equal portions to each of the velTels, after which 

 the 50 kilograms of decompofed rags are difpofed in equal 

 portions in each tub. The fluff is left for about twelve hours 

 in this bath, agitating it from time to time, after which it is to 

 be completely wafhed in clean water, and put into a bath of 

 fulphuric acid, compofed of water 200 litres, and acid at 50 

 degrees' three kilograms, which bath will then have the 

 Urength of about four degrees of the earomete*r of Baume. 



Hie immerlion in the bath mull: continue for three quartet* 

 of an hour or an hour, after which the materials muft be well 

 wafhed in clear water, and carried to the mill to be manu- 

 factured. 



If the action of the baths of bleaching liquor be not ex- 

 haufted by the imrnerhon of the decompofed rags (which may 

 be afecrtained by the folution of indigo), it may be applied to 

 other materials of the fame kind. 

 Improvements. Such was the ltate in which we left this new art in the 

 year 3. Since that time Citizen Welter, to whom chemiftry 

 and the arts are indebted for a number of ingenious procefTes, 

 lias Amplified that of preparing the bleaching liquor. He has 

 found, for example, that inftead of the three veflels of the re- 

 ceiver, it is fumcient to employ two even for the Ample 

 liquor that contains no fixed alkali. 

 Rife of the It was before feen that we were obliged to employ an alka- 



liquor without ]; ne f l u tion in the receiver, to prevent that odour which the 

 fimple liquor emits when paper iluff is agitated in the baths. 

 The ufe of alkali anfwercd- our purpofe very well in this re^ 



fpeft ; 



