METHOD OP BLEACHING PAPER. 12i" 



Tmis it was, that by fucceffively avoiding the extremes of too 

 much and too little mechanical connection, we advanced to- 

 wards our object. 



The apparatus which Citizen Welter imagined, and of Apparatus of 

 which Citizen Berthollet has given a defcription in the firft m^ulc'iA 0X * 

 volume of the Journal of Arts and Manufactures, is applicable 

 to all the methods which can be employed to procure the dif- 

 ferent kinds of bleaching liquor, whether the water of the 

 receiver contain fixed alkali or not; whether the muriatic 

 acid be ufed on the oxide of manganefe, or the gas be obtained 

 by fulphuric acid, upon the mixture of oxide of manganefe 

 and muriate of foda. This apparatus is particularly preferable 

 to all others in the cafe where the water of the receiver con- 

 tains no alkali, becaufe the abforption of the gas is favoured 

 by its being brought into contact with the water at a great 

 number of furfaces. But as we had determined to ufe a folu- 

 tion of potafli, we were able to make fome modifications of 

 this apparatus. 



1. The three inner partitions of the receiving vefTel were was con fidera- 

 reduced to one only. Ours was formed of a tub containing h] y fi m P llfied ' 

 another tub inverted, and both were covered with fheet lead. 



% The fize of the tubes of communication was fo confide- 

 rable, that we had nothing to fear from abforption during the 

 cpurfe of the diflillation. 



3. Laftly, the practical fkill of our workmen in managing 

 the fire, and the advantage of having only one opening to 

 Lute enabled us to fupprefs the intermediate veffel. 



Defcription of the apparatus ufed in preparing the ox ige- Defcription. 

 nated muriatic acid in bleaching the pafte of paper for affignats. 



Fig. 1, PI. VII. Plan of the apparatus. Plan. 



1, 1, 1, 85c. Eight furnaces, having a chimney of flieet 

 iron common to each pair of furnaces. 



2, 2, 2, &c. Eight veffels of call: iron, containing land. 



3, 3, 3, &c. Eight matrafTes, balloons, or bottles of 

 i~r one ware, compact and well baked, intended to contain the 

 materials which afford the gas. Each matrafs mufl be rilled 

 only to one-third of its capacity at molt. Bodies of glafs of 

 little thicknefs may alfo be ufed for this purpofe. 



4, 4, 4, &c. Tubes of glafs to conduct the gas into the 

 receiver. Or thefe tubes may be made of lead. 



5. The 



