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XLTV. Analyfis of the Schief erf path from Corntvalh, to "whkh 

 is prefxed an Analyfis of Carbonated Lime, and Remarks on 

 the Means luhich have been employed to afcertain the Quan- 

 tify of Carbonic Acid contained in it. By Mr. Richard 

 Phillips, Member of the Britijh Miner alogical Society*'. 



jl ROM forre experiments made upon the fchieferfpath, I 

 was induced to believe that it confifted of lime combined with 

 a much greater quantity of carbonic acid than, according to 

 the analyfis of Bergman (En^. edit. vol. i. p. 32.) is contauied 

 in carbonated lime. I refer to his analyfis of this fubftance, 

 fuppofing it to be the laft, and perhaps the only one ever 

 made of it, fince it is quoted by Haiiv, Traite d; Minera- 

 logie, tome ii. p. 128; and by Brochant, tome i. p. 548, as 

 well as bv other late writers on the fubjeft. By the analyfis 

 of Bergman, pure carbonated lime confiits of 



Carbonic acid - 34 



Lime - '55 



Water - - 11 



100 



In order to afcertain the quantity of water, which, as above 

 ftated, is very confiderabie, the following experiments were 

 made : 



Exp. T. 100 grains of pure carbonated lime (double re. 

 fra6ting fpar) were expofcd, in a filver crucible, to a red heat 

 for about twenty minutes. On weighing them when cold 

 they were found to have diminiftied 1'8 grain. It will here- 

 after be fliown that a part of this lofs was probably water: 

 yet a portion of it is to be attributed to the difengagement ot 

 carbonic acid ; for, upon putting the remaining carbonated 

 lime into water coloured blue by fyrup of violets, the folution 

 inftantiy aflumed a deep green colour. Hence it appears that 

 tliis method is not to be relied upon in order to diffipatc water 

 only. 



Exp.W. 400 grains of carbonated lime were introduced 

 into a coated glafs retort, having a receiver adapted to it. 

 Soon after the Application of heat, a very minuie quantity of 

 water appeared in the neck of the retort; but it was entirely 

 diflTipatcd before it had reached the mouth of it. Owing to 

 this, and the extreme fmallnefs of the quantity, it was entirely 

 impoflible to afcertain or even to ellimate its weight. No 

 more water appeared upon the application of a much Wronger 



• rdiniiiuniotu-J 'w tlu Author* 



\oC:\\V7H^/i. T heat 



January 1803. 



