^j4. ChfirvatUm m Strtntlati. 



were entirely difTolvcd. I put the whole into a m»trafs, and endeavoured to favour tlie 

 lulution by means of heat ; a portion of the fik remained, however, undilVolved at the 

 bottom of the niatrafs. 



Having fet the folution on fire, the akohol burned with a yellowifli flame. 



6. Fifty-four grains of cryftals of rtrontlan being treated comparatively with the fame 

 muriatic acid, the folution alfo took place with heat. The liquor being evaporated in an equal 

 degree with that of the muriate of barytes (which, although upon the fire, had already cryf- 

 tallized) ftill remained fluid ; but, on being taken off the fire, it cryftaliized in a mafs, and in 

 needles like muriate of Arontian. This fait is therefore more foluble in water than the mu- 

 riate of byrytes. The weight of the muriate of ftrontian obtained in this experiment was 

 thirty-eight grains. 



Tliis muriate is alfo more foluble in alcohol j for, having triturated twejve grains in a 

 glafs mortar with feventy-two grains of alcohol, they were entirely difiblvcd. I added, how- 

 ever, afufficient quantity of alcohol to make the whole lialf an ounce, as in the preceding 

 experiment ; and having tlitn fet it on fire, it burned witli a flame of a beaytiful red. 



7. A faturated [.iqueous] folution of pure barytes affbrds by the addition of a few drop» 

 of malic acid a white precipitate, which is nialate of barytes ; but the fame acid does not 

 produce any precipitation in a faturated folution of ftrontiau : it follpwSj therefore, that 

 malate of ftrontian is more foluble than malate of barytes. 



Thefe experiments continue, therefore, to eftablilh a djfferepce b<jt)»re,eBp.Vi,re .bar^te^S aod 

 pure ftrontian. 



Carbonate of ftrontian has hitherto been found only in one place ; Strpntian in Argyle- 

 fliire : but M. Meyer, apothecary at Stettin, has lately announced that this earth is found 

 in combination with fulphuric acid in the fulphatc of barytes at Freyberg in Saxony. In 

 fionfequence of this obfervation I analyfed ^ pieqe of barytlc fulphate from Saxony, but the 

 •arth which I obtained from it was only barytes, and not ftrontian. J prefume that the ful- 

 phate which I affayed was diflPerent from that of which M. Meyer fpeaks j but I have, at all 

 events, reafon to know that ftrontian exlfts in other places as well as Argylcfhire. Citizen 

 Guyot, who travelled into Scotland with the Citizen DelelTere, fent me fomc years Cncc 

 fcveral fpeeimens of minerals which he had himfelf procured on the fpot, amongft which 

 tliere is one which is labelled in the handwriting of Citizen Guyot '^ BaryUs from Lead, 

 hill:" in Scotland. I have exaniined this fpecimen, and find that it is carbonate of ftron- 

 tian. Its colour is a greenifli white, and it feems formed by the union of a number of 

 prifms, which gives it a ftriated appearance. Its fpecific gravity is 3.6195. This carbonate, 

 treated with muriatic acid, yields 31;- per cent, of carbonic acid gas, and affords a muriate 

 which cryftallizes in needles, and which, when diflblved in alcohol, communicates to it the 

 property of burning with a red flame : in ftiort, this muriate appears to me perfeftly fimilar 

 to muriate of ftrontian. I have alfo treated the ftone from Lcadhills with the other acids, 

 and the produfts which I have obtained demonftrate that the bafe of this carbonate differs 

 in no refpea from ftrontian : here, therefore, we have this earth as well as at Strontian, 

 and very probably the refearches of raiBeralogifts will difcoverit in many other places. 



II. AbflraFt 



