J2S METHOD OF BLEACHING PAPER* 



t Eft i mate of the increafe of expence occafioned m the Ope-* 

 ration upon a pile of 50 kilograms of the pafte of paper, 

 fuppofing one bath of the bleaching liquor and one of fulphuric 

 acid, which is moil commonly the cafe. , 



Ninety litres of the bleaching liquor at nine cents. 9c. 



8fr. 10c. 

 Three kilograms of fulphuric acid, at 



lfr. 50c. - - - 4fr. 50c. 



Workmanfhip - ---'• - 50c. 



Total 13fr. 10c. 



Which gives for each kilogram of paper an expence of 0,262 

 franks, or about 27 cents. Now the common paper in the 

 market ufually fells for about 1 fr. 30c. or lfr. 40c. the kilo- 

 gram, and with the fimple augmentation of 27 cents for the 

 operation.* of bleaching, it obtains the preference beyond that 

 which is fold for three, four, or even five franks, which can 

 only be obtained in limited quantity, on account of the {elec- 

 tion of rags. The foregoing methods mufl therefore produce 

 a great diminution in the price of fine paper. They are more 

 particularly advantageous when applied to the manufacture 

 of thin paper, becaufe the expences of bleaching are always 

 proportioned to the weight of the material, and confequently 

 are leaft upon thin paper. 

 Diflilling appa- I fhall conclude this memoir with a defcription of an ap- 

 r a tusof^^.p aratus i nvente d bv Citizen Athenas, for preparing the oxi- 

 genated muriatic acid. He had the complaifance to lend it 

 to us. This apparatus is remarkable for its fimplicity, as it 

 requires no veilels of earth or glafs, nor intermediate veffels, 

 nor tubes of communication. 



Fig. 4, Plate VII. reprefents the horizontal fection, and 

 Fig. 5 the vertical fection. The defcription of this laft will 

 be fufficient to explain the conftruclion. 



9 reprefents the ath-hole. 



10 the fire-place, having its chimney turned on one fide. 



11. An iron boiler, containing water kept at the heat of 

 ebullition, ferving as a bath for the cucurbit, and effecting the 

 difengagement of the gas. 



12. The diftilling veffel of lead, in which the fubjeel mat- 

 ters^of the operation are put. 



13. A 



