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472 Tkird Appendix. earths are contained in the folution, as this an- pearance would take place if calcareous earth alone exifted in it. 55- Jhisdoubt, however, may be refolved bv ^ v ®Porating the folution in a moderate degree, and u enng it to cool; for, firft, the nitrated ba- i'}'tes J and then the nitrated fixonthian, would cryf- tahze; the nitrated calx, not. The nitrated ftron- thian is foluble in once or twice its weight of water; the nitrated barytes requires much more. • u • • • 1 betrer ’ b y precipitating the whole with vitriolic acid, filtering and evaporating the remainder nearly to drynels, to obtain the whole o the fclenite, if thcrebeany, the depofite on the filtre will then be freed from felenire by repeated affufions of hot water, and the folution, by eva- poration, will depofite it, adding fpirit of wine towards the end. 57' This being done, the precipitate on the filtre can now confift only of vitriolated ftronthian and baryns; to feparate thefe, the dried mafs mutt be heated with two and a half times its weight of dephlegnrated aerated foda to rednefs, for an hour or more, in a filver crucible, and then the alkahne matter Vvafhed offon a filtre. 58. The depofite on the filtre, ignited and vteigbed, fhould then be treated with nitrous acid, which will hold both the fironthian and barytic earths diffolved; the folution, havincr been boiled for fi.me time, may be heated with arytic lime-water, which will precipitate the baTyt'ic'^*’ ^ an> CXiflS ln ir ’ If n ° r ’ k is Wh ° lly 50. If fironthian exifts in it, it will be Ieft on the filtre 1,1 the ftate of lime, which Ihould again be reduio.ved in nitrous acid, and prccipitatcd by 3 mild