520 Qbfervatictu an Slrtirluin. 



Secondly, Tliat it produced with the iiiuic, muriatic, and other acids, falts which were 

 more foluble than thofc of barytcs ; 



Thirdly, that the fait wlach it formed with the muriatic acid, being diflblved in alcoho^ 

 gave it tlie property of burning with a red flame ; 



Fourthly and laftly, That it might be deprived of its carbonic acid by calcination ; and that 

 it became by this means foluble in water, and the raoft fo in boiling water ; fo. that by 

 cooling a portion was fcparated in a cryftalline form. 



The fpecimen of carbonate" of (Irontian, which I had in my coUeclion, was not confide- 

 rable enough to admit of a great number o( experiments -, it was howcvtr fuHicicntly fo to 

 enable me to repeat a part of thofe which arc related by MetTrs. Hope and Klaproth ; and 

 what niollly determined me to appropriate it to this purpofe was, that Cit. Coquebert had 

 publiflied in No. 5 of the Journal des Mines, that from fomc afliiys which we had made of 

 the carbonate of ftrontian, I had doubted whether it contained a peculiar earth. The fol- 

 lowing arc the reafons on which my doubts were founded : 



1. Jt isfeveral years fince I had fucccedcd in difengaging carbonic acid gas from carbo- 

 nate of barytes by calcination ; and, having then difTolved the calcined barytes in hot water, 

 had obtained a cryftallization : I could not therefore confider this charader as exclufivel/ 

 belonging to ftrontian. 



2. I knew alio that calcareous muriate difTolved in alcohol gave it the property of burn- 

 ing with a red flame. This confideratlon induced me therefore to fufpedl a mixture of 

 calcareous carbonate in that of ftrontian, and the fpecimen which I had was in faft com- 

 bined with this fubftance. I fliall now dcfcribe the experiments which I have made to en- 

 deavour to dete£l this ingredient ; and, as they were made comparatively with a fimilar fet 

 on the native carbonate of barytcs (witherite), I have thought it proper to prefent them to- 

 gether, that it may be feen in what refpeds the carbonate of ftrontian rcfembles, and ia 

 what it differs from it. 



Compar'ifon of Stiontiaii ami Barytcs. 



1. CARBONATE of barytes is found with fulphate of barytes in a lead-mine atAnglezarlc, 

 (ncir Chorley)in Lancafliire*. Carbonate of ftrontian is found at Strontian in Argylefliire, 

 alfo accompanying a lead-ore with fulphate of barytes. 



2. The carbonate of barytes from Anglezark, taken internally, is poifonous, fo that in 

 that country it is^known by the name of rat-ftone [pierre contre les rats]. A little dog to 

 which I had given fifteen grains was feized with vomiting, and died eight hours afterwards ; 

 and having given to another^of apparentlyequalftrength fifteen grains of carbonate of barytcs 

 obtained from the decompofition of the fulphate, it was alfo feized with vomiting, and died 

 fifteen hours afterwards : the latter was opened by Cit. Chauffier. Another dog to whicli 

 I had given a like quantity of carbonate of barytes, prepared from fulphate of barytes from 

 the ci-devant province of Auvergne, had vomitings, but did not die, though he took it 

 two days fuccciRvely : he vomited each time. I purpofe to repeat thefe experiments with 

 carbonates of barytes procured from different barytic fulphates, and cfpecially thofc which 



jre not accompanied by any metallic ores. The carbonate of ftrontian, on the contrary, 

 may be taken internally without danger. I gave 20 grains of it to a little dog, but he was 



■• Sccilie Manchcflcr Mcmuirj, iii. 548. T. 



not 



