Revolving DoiilIei'.-—SJturation ef Alkali luith Carben'tc Acid. 369 



gives a defcription of my inftrument in my own words, copied without acknowledgment 

 from the Philofophlcal Tranfadions for 1788, but difguifed in a fmall degree by a new de- 

 nomination in the title, and an unneceflary lengthening of the infulating parts, which 

 before were upwards of ten times the length of the interval between plate and plate. It 

 is evident, therefore, that of all the individuals who have written on this inftrument, the 

 credit of the invention has, in t 798, been beftowed on the perfon who has the leaft claim 

 to philofophical invention or candid narrative. 



XIV. 



Defci iption -of. an Apparatus for fatttrating PoUaJb and Soda with Carbonic Acid, 



By Citizen WeltheR*,- 



T . . > . 



X H E intention of this apparatus is, to afford an uninterrupted contaft between the 

 alkali and the carbonic acid gas,, and to proportion the difengagement of the gas to its 

 fixation. 



Fig. I. platt XVI. reprefents the complete apparatus. It is compofed of four diftinift 

 parts, A, B, C, D. The firft. A, ferves for the difengagement or production of the car- 

 bonic acid gas, whence it is diilributed into the apparatus. The fecond, B, conne£ts all- 

 the feveral parts of the apparatus together. The third, C, is the refervoir for carbonic acid- 

 gas. 1 he principal funflion of this part is to fupply gas to the alkali in proportion as the 

 abforption takes place. And the fourth, D, contains the alkali which is to be faturated, ilk' 

 cx)nta£t with the carbonic acid.' 



Each of thefe parts requires a particular defcription. 



The part A, confifts of a bottle with two necks a, by (the third, c, is not heceflary). This- 

 bottle contains fulphuric acid diluted with four parts of water, to the height d. — Tihe neck a, • 

 receivesatubeif'^'^, of which the upper part /<•', diverges Hke the bafe of a funnel, and the 

 lower part f, which paffes through the cork and enters the bottle, is drawn out by the lamp, , 

 in fuch a manner, that the portion of tube which is in the ftopper has the fame internal dia- 

 meter as the extremity 1: of the ftem/, reprefentedj*^. 2, A; and that the orifice r within' 

 the bottle, is only two millimetres in diameter (^y of an inch) |. Into the tube^V* 

 enters the ftem or ftick of glafs fy reprefented fg. 2, , A, the lower extremity of which is ■ 

 bound with flax, fo that it ferves as a ilopper in the.contradted part of the tube, and does 

 not permit its contents to flow into the bottle a, unlefs that ftopper be raifed. — The neck b' 

 contains a tubei/.i/j bended into two angles, and forming a communication between A'- 

 andB. 



The part B, confifts. of a bottle with five necks a bfi h, of which the plan is reprefented ' 

 jig. 3, 3. This bottle contains water as high as /. — ^The neck h receives the tube h h h^. 



• This apparatus was conftrufted in die firft month of the third republican year.' . The defcription i> tranflatej : 

 from the Annalcs de Chimie, xxv:i. 53. 



f. The tube e" c' e may be made out of a fmall matrafs with a long,neck. The bottom may be taken away, . 

 leaving about half the lioiiy, wh'.ch will form the pan c' e' of the tube ; the neck will afford the partaa, and the . 

 extnemity of the neck foftentd and drawn out by the lamp to the above dimenfioas, will afford the extremity e, W. ■ 



proceeding ; 



