EXAMINATION OF THE OCHROITES. 211 



binatlon may be decompofed by boiling it with double Its weight may be decom- 

 of carbonate of foda. By this means ochroit earth may be ^''.^f by boiling 



... •' ■' With catb. of 



obtained very pure. foda; and the- 



9. Ochroit earth is likewife foluble in fulphureous acid, the earth obtamd 

 folution cryftallizes in needles of a pale amethyft colour. ^\ Sulphureous 



10. Muriatic acid difTolves ochroit earth, and yield* cry- acid diflblves 

 flals, the figure of which is the prifm. It is foluble in alcohol cryiJfiJ'/bliV 

 without imparting to its flame any particular colour. v Muriatic acid 



12. Acetite of ochroit could not becryftallized, but yielded ''^" ^'^f^' 'f' 



'' ' ■' and cryftaibzes. 



an adhefive mafs. ' The alcohol fo- 



13. Nitrate and muriate of ochroit is decompofable by 



car- 



lution does not 

 , , , , , , ,• , • • ■ -11 . colour flame. 



Donated earths and alcalies, the precipitate is milk-white. Acetite of 



Alcalies and earths freed from carbonic acid, occafion a yel- ochroit not ciyf- 



, -n . . ^ t^llizable. 



lowifh grey precipitate. ^ ^ " The nitrate and 



14. Pruffiate of potadi precipitates ochroit from all Its neu- niuriate precipi- 

 tral folutions, milk white. The precipitate is foluble in mu- Tn^J^ilk^anr^' 

 riatic and nitric acid.* and byprudiate 



15. Tindure of galls occafions no change in the folutions of wh>°'^^ ' 

 this earth. Not by galls, 



16. Hidroguretted-hidrofulphuret of ammonia precipitates but by hidrog, 

 the folution of ochroit earth, yellowifh white. ^''^'^"- (^"'P^' '^^ 



17. Water impregnated with falphuretted hidrogen occa- Not by hidro. 

 fions no change in the folutions of ochroit earth. iM\^h. water, 



IS. Succlnales precipitate ochroit earth white, t"t by fucci- 



19. Phofphate of foda, occafions in the folutions of this p|^Qf*1^3j.g ^^ 

 earth a white precipitate, which again vanifhes by the addition foda precipitates, 

 of nitric or muriatic acid. ^' 



20. Tartrites of potafh alfo precipitate this earth white. Tartrltes preci- 



21. Oxalates effed a like decompofition, the oxalate of a^j o^.'^fg^gj^ 

 ochroit, however, is not foluble in nitric or muriatic acids. 



22. Alcalies and alcaline carbonates do not a£l on ochroit Alcalies do not 

 ^2^x{\\ ^^ °" '^^^ earth» 



23. Ammonia feebly acts on it, under certain circumftances. Ammonia 

 as may be evinced from the following experiment : feebly. 



A folution of nitrate of ochroit, prepared by difTolving 100 

 grains of carbonate of ochroit (not abfolutely free from iron,) 

 in nitric acid, was decompofed by carbonate of ammonia, and 

 digefted in the fluid, containing a confiderable quantity of 

 carbonate of ammonia in excefs, for (bme days. The fluid 



* If the earth contained the muriates and quality of iron, it be- 

 comes by this means manifefted. 



, P 2 w hich 



