^0 Saturation o/Alhali with Ccirhtnic Acid. 



proceeding from tlie bottle A. — The neck b contains a ftrait tube g g\ wbofe extremity g' 

 is plunged in the water to the depth of one or two centimetres (about \ of an inch.) It 

 ferves to (hew the comprcflion to which the carbonic acid gas is fubjefted in the apparatus. 

 — The neck a contains a ftiait tube a' a, which allows a communication to be formed at 

 ■plcafure from the interior part of the bottle B, with the atmofpliere, by means of an appara- 

 tus of tubes fhewn in^^ 4, B. The tube a' a has two ftoppers at m and n : the flopper m 

 enters the tube w w, enclofing the tube a' a ; in tlic interval between thefe two tubes upon 

 tlicftcpper m, mercury ij poured to the height r of twelve or fifteen millimetres (about |- 

 ah inch) : the tube a' a is then covered by a third tube Jclofed above, which being in>mer- 

 fed Tit pm into the mercury, interrupts the communication of the atmofphere with the 

 orifice a' of the tube a' n, and confequently clofes the bottle B, when the ftopper /; is placed 

 in the neck a. — The neck / contains a tube / ;, compofed like the former a' a ; but of which 

 the intermediate tube 000 twice recurved, eftabliibes a cominunication between the bottle 

 B and the rei'ervoir C. — The lafl neck y contains a tubey//', twice recurved, which elta- 

 blifhes a communication between the bottles B and D. 



The partC is compofed of a tub /, in the fide of which there is a hole at a fmall diftance 

 above the bottom a a. — In this lateral hole is inferted a perforated ftopper, the interior ori- 

 fice of which receives a tube bl'b"b, bended into a right angle, of which the portion b' mud 

 be bended in fuch a manner, that the angular part h" may touch the bottom a a oi the tub, 

 which renders it more firm in its pofition. In the external orifice of this cork, or ftopper, 

 there is fcrewed a brafs cock r, of which the part c receives a tube c c' c" c, bended at <•, 

 to rife vcrtlcailly, and from c'toc"t.o bind againft the frame del. This tube, at the height^, 

 is compofed like that of a' a, defcribed7%. 4, B. It there receives the tube 000, which affords 

 a communication with B. — The pieces which are applied to the hole b of the tub, are luted ; 

 the inner with graver's wax, and the outer with fat lute. — In the tub /, containing water 

 to the height e ee, there enters an inverted jar C, provided with a copper cock at / and m. 

 This jar is fufpended at g by a ftring, which paffes over the pulleys h h, and fupports at /, a 

 weight K, fomewhat lefs heavy than the jar itfelf, when entirely plunged in the water con- 

 tained in the tub. — When the jar C is totally immerfed in the tub, it will reft on two pieces 

 of wood about two or three centimetres thick, which are fixed at ///near the inner circum- 

 ference of the bottom a a oi the tub (feefg. 5, C, which reprefents the plan of the tub j 

 and Jig. 6, which reprefents the vertical fcdion as far as A B), fo that the bafe /' /'/' of the 

 jar cannot touch the tube b. 



The p:.rt D confifts of a bottle with three necks, a, b, c. The neck a receives a tube 

 oa' a, proceeding to a fmall bottle d, containing water as high as e. — The neck b receives 

 the tube ///' proceeding from the bottle B -, this tube ought to poflefs a diameter of about 

 two centimetres (| of an inch) at its orifice/'. — The neck r contains a fyphon gg', commu- 

 nicating with the bottle /, of which the branch g ' ought to be longer than g. — The bottle / 

 has three necks, h, i, i. — It receives in its neck i, the fyphon gg'; in the neck i, a tube b by 

 ■with one fingle bend ; and the neck « remains free. It is to be corked. 



After the formation of the apparatus by uniting the four parts here defcribed, each of 

 *hem demands a particular preparation before the operation can be proceeded upon. 



The tube / e^ e oi the part A is to be filled with carbonate of lime mixed with water.— 

 Through the neck/?i of the bottle /, in the part D, that bottle is to be filled with alkali. The 



neck 



