290 Analyfis of Carbon a led Lime. 



heat to the retort. This cxpenment was repeated with fimi- 

 hir refuUs. 



Exf>. III. To find the quantity of carhonic acid conlaincd 

 in carbonated Hme, I made life of a vellel nearly finiilar to 

 that dcfcribcd in ^page ;^6^ of the lath volume of the Phi- 

 lofophical Magazine. 



Into this veflbl was put a fufficient quantity of nitric acid 

 of the fpeuitic gravity 1'40, noting at the fame time the 

 aggregate weight of the vial, tube, and acid ; and ico grains 

 of fragments of carbon.iled lime were gradually added to the 

 nitric acid. H hen the lad portions of it were decompofed, 

 on weighing the vial, &c. it had received an addition of ^6 

 grains. Hence 44 grains, which were carbonic acid, were 

 e.vpclied. On repeating this experiment with quantities of 

 carbonated lime greater than 100 grains, proportional refults 

 were afforded. 



Exp. IV'. To determine the quantity of lime, 100 grains 

 of carbonated lime reduced to powder were put into a piatina 

 crucible, and llrongly heated in a wind-furnace for about two 

 hours : the refidiuim was pure lime; it weighed 55*9 grains. 

 Upon repeating this experiment! obtained a refidutim weigh- 

 ."'£ 55''^5 grains. Thefe refidts differ but little : their mean, 

 J)S'475> is therefore aflumed as the quantity of lime con- 

 tained in ICO parts of the carbonate. 



According to the above experiments, carbonated lime con- 

 tains Carbonic acid - 44 



Lime - - 55'475 

 Water and lofs '525 



In comparing the above with the analyfis by Bergman 

 there appears a difference of 10 of carbonic arid and nearly 

 lO"5 of water. Kirwan, (Mineralogy, vol. i. p. 87.) on 

 remarking the difference of the quantities of carbonic aoid 

 obtained by himfelf and Bergman, fuppofes the latter em- 

 ployed fulphuric acid to difengage the carbonic: and this 

 conjet'-ture feems well founded; for, if carbonated lime be put 

 into fslphuric acid, the fulphate of lime formed, and falling- 

 down infolubk, fo envelops a part of the carbonated lime 

 that thie complete aftion of the fulphuric acid is prevented : 

 and as it does not apjtear that Bergman obtained the water 

 by direct experiment, he feems to have aflumed its quantity 



* Tlie experiments there related upon the fatin fpar were repeated ; 

 but it did not appciir to contain more than the ufual proportion of carbonic 

 itcid. . 



froni 



