BAIRD &TATLOCKL (LONDON) LTD. 



5210 



5212-5213 



2 2 



5210 Calcimeter, Scheibler's, for the quantitative estimation of carbonate of lime, on stand 

 complete 



DESCRIPTION OF SCHEIBLER'S CALCIMETER. 



The carbon dioxide in a carbonate may be estimated by liberating the gas by means ol an acid, and then 

 measuring the volume of the gas. From this the weight of the carbon dioxide can be calculated , and consequently 

 the weight of the carbonate itself, provided it is of known and definite composition. 



Scheibler's apparatus was originally designed for estimating the amount of calcium carbonate present in the 

 bone black used in sugar refining, and has the advantage of being rapid and simple in use. 



Description of the apparatus. The apparatus consists of (i) a vessel in which the weighed quantity of carbonate 

 is decomposed, and containing a glass or guttapercha tube of about 12 cubic centimetres capacity in which the 

 acid required for the decomposition is placed. The vessel is closed by a sound perforated rubber cork, into which 

 a short bent glass tube is fitted. This is connected by means of rubber tubing with the centre vessel (2), from 

 which the gas displaces air into the measuring apparatus. The vessel is closed by a cork with three perforations. 

 Through one a bent tube passes connecting the first vessel, into another is fitted a long vertical tube connecting 

 the centre vessel with the measuring apparatus, and into a third is fitted a short piece of glass tubing terminating 

 in a piece of rubber tubing, closed by a spring or screw clamp. This serves to connect the apparatus with the 

 atmosphere at will. The use of the balloon shown in the sketch may be dispensed with. The measuring apparatus 

 consists of two tubes firmly fastened to an upright board. These tubes are connected together below, and the 

 left-hand tube is connected with a Woulff's bottle containing water and employed for adjusting the water-levels 

 in the measuring tubes. The right-hand tube has a capacity of 150 cubic centimetres, and is accurately graduated 

 in half cubic centimetres. After fitting up the apparatus it should be proved to be air-tight by adjusting the 

 water-level in the graduated tube at a much higher level than that of the other tube, and allowing the apparatus 

 to stand for fifteen minutes. 



52 11 T Tubes, guttapercha, 3 by f in., for use with above .. .. .. .. each 016 



5212 Hall and Russell's Apparatus, for determining small quantities of carbonates 



Without Stand . . . . . . . . . . . . . . . . 15 



5213 Hall and Russell's Apparatus, for determining small quantities of carbonates With 



Stand, copper bath, etc. 



(See Journal of Chemical Society, No. cccclxx., January, 1902, p. 83.) 



1 15 



(CHEMICAL AND SCIENTIFIC" APPARATUS AND PURE CHEMICALS- 



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