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XLVI. Extract from M. Klaproth's Memoir upon the Sulphuric 

 Acid. Read at the Philomathic Society of Berlin. 



_L HIS memoir has for its object to determine the re- 

 spective quantities of the elements of the sulphuric acid, 

 and of sulphate of barytes. It details the analyses made 

 of these substances by the following different chemists. 



According to Lavoisier, the sulphuric acid is formed of 

 0-69 of sulphur and 0*31 of oxygen. 



According to Berthollet, it is formed of 0*72 of sulphur 

 and 0-28 of oxygen. 



M. Thenard gives 55-56 of sulphur and 44*44 of oxygen, 

 as its component parts. 



According to Chenevix, it is formed of 51-50 of sul- 

 phur and 38-50 of oxygen. 



According to Tromsdorff, it contains 70-00 of sulphur 

 and 30-00 of oxygen. 



According to Richter, it contains 42*05 of sulphur and 

 57*95 of oxygen. 



Finally, according to M. Bucholz, it is formed of 42*05 

 of sulphur and 57*05 of oxygen. 



From the above results, it is evident that the two last 

 analyses, although made in a different manner from each 

 other, have the strongest resemblance, and consequently 

 are best entitled to confidence. 



M. Klaproth, however, is of opinion that he ascertain- 

 ed, by his own experiments, the respective quantities of 

 the elements of sulphuric acid, and which he made that 

 he might apply the results afterwards with more certainty 

 to the analyses of pyrites or metallic sulphurets. In or- 

 der to attain this object, he employed, like his prede- 

 cessors, the nitric acid and carbonated barytes : the pro- 

 portion of the elements of the latter he had previously 

 determined to be 78 of barytes and 22 of carbonic acid. 



But M. Bucholz has since asserted that there are in 

 this salt 79 of barytes and 21 of carbonic acid. M. Klap- 

 roth has therefore repeated the analysis with every pre- 

 caution, and has again obtained the same results as before. 

 M. Bucholz also only admits of 25 of carbonic acid in 

 strontian, while M. Klaproth found 30 in all the analyses 

 he made of this substance. 



The results obtained by the analyses of sulphate of ba- 

 rytes, as made by various chemists, are not less at variance. 

 According to Fourcroy, it is composed of 66-00 of ba- 

 rytes and 34-00 of sulphuric acid. 



' Messrs. Clement and Desormes give 67*82 of barytes 

 and 3218 of sulphuric acid as its component parts. 



Vol. 25. No. 100. Sept. 1806. T M. Thenard 



