FALLEN ON THE EARTH. 97 



of extraneous earthy matter ,• and yielded, by the treatment 

 with nitric acid and ammonia, 17f grains of oxide of iron* 

 This would feem to iuduce an eftimation of If of nickel in 14 

 grains, or about 9 per cent. 



55 grains of the earthy part of the (lone, by the analytical Component 

 treatment of the two former, afforded, parts * 



Silica 25 



Magnefia 9^ 



Oxide of iron - - Q3~ 



Oxide of nickel - - 1 \ 



The unufual increafe of weight in the refult of the three la ft 

 analyfes, notwithftanding the intire lofs of the fulphur in the 

 pyrites, is obvioufly owing to the metallic ftate of the iron 

 combined with the fulphur, as was (hewn in a former inftance. 



I have now concluded the chemical examination of thefe Remarks on 



four extraordinary fubftances. It unfortunately differs from thefe an f ^ : 

 ,, , r . . . „, , , . . J compared with 



the analyiis made by the French Academicians, or the ftone thofe formerly 



prefented to them by the Abbe' Bachelay. as well as from that made b y otlvcrs ' 

 made by Profeflbr Barthold, of the ftone of Enfifheim. It is 

 at variance with that of the Academicians, inafmuch as they 

 found neither magnefia nor nickel. It differs from that of 

 Mr. Barthold, as he did not find nickel, but difcovered fome 

 lime, with 17 percent, of alumina. With regard^ thefe dif- 

 ferences* I have to fubmit to the chemical world, whether 

 magnefia might not have eluded the a&ion of an acid, when 

 the aggregation of the integrant parts of the ftone was not de- 

 ftroyed by treatment with potafh. As to the exiftence of alu- 

 mina, I do not abfolutely deny it; yet I muft obferve, that 

 the whole of the earth which feemed to have any refemblance, 

 however fmall, to alumina, was at moft 3 per cent, and there 

 feems good reafon to confider it as filica. Refpecling the ex- 

 iftence of lime in the ftone of Enfifheim, I muft appeal to 

 Profeflbr Barthold, whether, fuppofing lime a conftituent part, 

 fulphate of lime fhould not have been formed, as well as ful- 

 phate of magnefia, when fulphuric acid was generated by ig- 

 niting the earths and pyrites. And, as to the proportion of 

 alumina, in the fame ftone, Iwouldafk, at leaft, whether it 

 would have been fb confiderable, if the folutions formed by 

 acids, after the treatment with potafli, had been evaporated 

 Vol. III.— October, 1802, H to 



