Analyfis. 4 75 be fufpe&ed, the folution may be treated with. vitriolic acid, as fhewn from No. 7 to 10 inclu- fively. 66. We now re turn to the phofphorated calx, No. 64; this fhould be diffolved in four times its weight of nitrous acid; after folution, the vitriolic acid fhould be added as long as any prc- cipitate appears, the whole fhould then be filtred, and the felenite on the filtre wafhed with dilute fpirit of wine‘; the filtred liquor fhould then be copfiderably evaporated, to make it depofit the whole of the felenite; the fpirit of wine. may alfo be added to promote its feparation, 'and the whole afterwards caught on a filtre. 67. The felenite being thus expelled, the liquor fhould againbe fiightly diluted, and kept in aboiling heat, 10 expel the nitrous acid; the phofphoric will foon after thickcn, and often grow purplifh« from manganefe contained in it; the glafs con- taining it fhould then be taken up and weighed; that this acid is the phofphoric may be evinced by its copious precipication of lime-water, b.y its giving white precipitates with the folutions of Vitriol of iron, and nitrated mercury, and its ina- biiity to precipitate the folutions of nitrated or muriated barytes. 68. '1 he felenite is next to be decompofed by boilincr it with mild foda, as in No. 10. 69°The depofite on the filtre, No. 63, if any be, fhould next be examincd; it may contain gypfum, barofelenite, argill, filex, and calces of iron, the feparation has been already fliewn, from No. 35 to 41. Phofpholitc fhould alfo be diftilled with its own weight of ftrong vitriolic acid, to difcover whe- ther it contains the fluor acid, as it; often does; the fparry