MINERAL from GREENLAND. 393 



6. The black refidue which the potafh-ley had not taken up, 

 was diflblved in diluted fulphuric acid. The folution being- 

 evaporated to drynefs, and the refidue digefted in hot water, a 

 white foft powder regained, which, heated to rednefs, weighed 

 3.6 grains, and was fulphate of lime, equivalent to about 2 

 grains of lime. 



7. The liquid from which the fulphate of lime was fepa- 

 rated, being exactly neutralifed by ammonia, fuccinate of am- 

 monia was dropped in; a brownifh-red precipitate fell, which, 

 being heated to rednefs in a covered crucible, weighed 1 grain, 

 and was black oxide of iron. 



8. The refidual liquor being now examined by different re- 

 agents, nothing farther could be precipitated from it. 



9. The liquid (No. 4.) from which the alumina, lime, and 

 iron had been feparated by carbonate of potafh, being boiled 

 for fome time, let fall a fmall quantity of yellow-coloured mat- 

 ter. This matter being digefled in diluted fulphuric acid, part- 

 ly diflblved with effervefcence ', but a portion remained undif- 

 folved, weighing 1 grain. It was infoluble in acids, and with 

 potafh melted into a colourlefs glafs. It was therefore filica. 

 The fulphuric acid folution being evaporated to drynefs, left a 

 refidue, which poflefTed the properties of fulphate of lime, and 

 which weighed 1.2 grains, equivalent to about 0.7 grains of 

 lime. 



10. The conftituents obtained by the preceding analyfis be- 

 ing obvioufly defective, it remained to examine whether the 

 mineral, according to the conjecture of Bournon, contained 

 an alkali. For this purpofe, 100 grains of it, reduced to a fine 

 powder, and mixed with 500 grains of nitrate of barytes, were 

 expofed for an hour to a red heat, in a porcelain crucible. The 

 fufed mafs was foftened with water, and treated with muriatic 

 acid. The whole diflblved, except 25 grains of a white pow- 



Vol.VI. P. II. 3D der, 



