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b. To tlie nitrous folution was added afoiution of muriated .foda by which a precipitateof 84.75 grs. of muriated filver was obtained.

c. The remaining filtered folution wastefted with fulphat of foda, but no precipitationtook place, thus (bowing the abfence of lead.An excefs of caufiic ammonia was then addedwhich threw down a grey precipitate weighing5 grs. This when heated exhaled a (lightarfeuical odour, and being difl’olved in nitricacid afforded a deep blue precipitate withpruffiat of potalh: thus thowing it to be oxydof iron with a little arfenic.

d. The ammoniacal folution which had a lightblue colour, was (lightly fuperfaturated withfulphuric acid, a polifhed piece of iron beingthen inferted was tinged with copper, but in lofmall a quantity as not to be afcertained.

e. The portion of the ore (a.) infoluble innitric acid was digefted in nitro-muriatic acid,and the part not taken up by this menftruumamounted to 13 grs. of which 12 were burntoff on a tell, and were fulphur; the remainderwas (ilex.

f. The nitro-muriatic folution being pouredinto water depofited 13 grs. of oxyd of anti-mony.

5. iVbite fiver ere.

a. 400 grs. of this being pulverized, weremixed with 4 oz. of ftrong nitric acid, and 2oz. of water. After the menftruum hadceafed to a£t it was poured off and replaced by2 0Z. of nitric acid, to which, after being di-gefted for fome time, were added 8 oz. of water,and the whole was boiled. The undiffolvedrefidue after edulcoration weighed 326 grs.

b. To the nitrous folution was added com-mon fait by which muriated filver was imme-diately precipitated, and after a few hours werealfo depofited cryftals of muriated lead. Themixed precipitate was boiled with much water,by which the muriated lead was difiolved, andthe muriated filver obtained pure ; from thisby fufion with foda were obtained 81.5 grs. offilver.

c. The two folutions being mixed together,there was added pure ammonia to faturation,which threw down a light brown fediment,weighing 40 grains. This was rediffolved innitric acid, and by the addition firft of pru-fiated potalh, and then of foda, was feparatedinto 1'2 grs. oxyd of iron and 28 alumine.

d. The undiffolved refidue (a) was boiledin repeated portions of muriatic acid, and atlength there remained only 51 grs. which■when ignited proved to be 49 grs. of fulphur,

and 2 grs. of a refidue, half of which was filexand the other part being foluble in muriaticacid, was added to the other muriatic folution.

e. The muriatic folution was repeatedly eva-porated till it ceafed to depofit cryftals. Thefebeing collefted, and mixed with twice theirweight of black flux, were reduced in a linedcrucible, and afforded i6o|-grs. of lead. T hislead when cupelled emitted a few antimonialvapours, and left behind -j of a grain of filver.

f. The muriatic folution, after the mu-riat of lead had been feparated, was pouredinto water and depofited a white oxyd of anti-mony, which being mixed with foap and blackflux was reduced by fufion to the metallicftate. In this procefs however a (light portionof the antimony was volatilized; what re-mained weighed 31.5 grs.

6. Grey ftlver ore.

a. 300 grs. of this were pulverized and di-gefted with four times their weight of nitricacid} when this had ceafed to add it waspoured off and replaced by another equalquantity of the fame acid. The undiffolvedportion was of a greyifh yellow colour, andweighed 188 grs.

b. To the bright green nitric folution wasadded a folution of muriated foda, and the pre-cipitate thus obtained afforded by fufion withfoda 31,5 grs. of filver.

c. The filver being thus feparated, fulphatof foda was added, but without occafioningany precipitate, therefore the liquor containedno lead.

d. Cauftic ammonia was then added tofuperfaturation, upon which a brownifh redfediment fell down, which when ignited weigh-ed 9.25 grs. By digeftion in nitric acid itdiffolved, with the exception of 0.5 gr. of filex.Pruffiat of potalh threw down from the folutiona deep blue precipitate, after which 1.5 gr. ofalumine was obtained by means of foda. Hencethe oxyd of iron amounted to 7.25 grs.

e. I he blue ammoniacal folution was nowfuperfaturated with fulphuric acid, and a pieceof polifhed iron procured from it 69 grs. ofcopper.

f. The infoluble portion (a) was boiledwith fix times its weight of muriatic acid,which being poured off when its a&ion hadceafed, there remained 105.5 grs (till un-diffolved.

g. The muriatic folution being concentratedby evaporation, depofited a little muriat offilver, from which 0.25 gr. of metal wasobtained. The fluid being then poured into