ObprvStidti} on Stn/ithn. 5 1 9 



M. Klaprothhas alfo examined ftrontjati, but, as ii appears, fubfequently to Dr. Hope j 

 or at lead, as he does not fpeak in his work of Dr. Hope's experiments, there is reafon to 

 beheve that they were not known to him. 



Strontian is alfo mentioned in M. Schmeifler's mineralogical work, as different from the 

 other known earths. 



It is in the flate of carbonate that it is found in Argylefliire in the weftern part of the 

 north of Scotland, accompanying a vein of lead-ore. 



Klaproth^ Blumenbach, and Sulzer of Ronnebourg, cMcd it Jl^rutianite; Hope called 

 itJ!rontile. I conceive that the name oi Jirontian, taken from the place where it is found, 

 may be properly affigned to it, as this word in itfilf has no fignification, and cannot confc- 

 quently render it liable to be confounded with other fubftances. 



The carbonate of ftrontian has been for a long time confidered as a variety of native car- 

 bonate of barytes ; 1 myfelf looked upon it as fuch in 1791, from forae aflays to which I 

 had fubjeited a fmall fpecimen, which Mr. Grevillc of London had the goodnefs to pro- 

 cure me. Having affayed it comparatively with the carbonate of barytes from Anglezark, 

 which was then called witherite, I thought I did not at that time perceive any remarkable 

 difference between the two fubftances. Both of them when fufed by the blow-pipe afforded 

 white opaque vitreous globules, which, when expofed for fome time to the air, became re- 

 duced to powder. Expofed to diftillation in a moderate heat, carbonate of ftrontian does 

 not, any more than carbonate of barytes, emit any carbonic acid gas, though they are both 

 diffolved by the nitric and muriatic acids with effervefcence and a difengagement of this 

 gas. The falls which refulted from thcfe combinations were by no means deliquefcent, and 

 I therefore took thofe of the ftrontian for nitrate and muriate of barytes, and ftill rather 

 becaufc their folutions were decompofed by the alkaline, calcareous, and other fulphates, 

 as is the cafe with the barytic falts. 



It is fome months fincewe have been acqifainted in France with the labours of M. Khp- 

 roth on the carbonate of ftrontian ; but thofe of Dr. Hope, although prior, were unknown 

 «o us, and it is only within a few days that I have been apprized of them by M.Schmeiffer. 



In a letter which M. Hermbftcedt wrote me Gx months ago, he announced that M. Klap- 

 Toth had eftablifhed the properties of ftrontian as a new earth, the difcovery of which had 

 been made feveral years fince by M. Sulzer, and had been publiftied by M. Biumcnbach in 

 his treatife on natural hiftory. I'he diftinclive ch^.ra£ters which M. Klaproth had found in 

 the carbonate of ftrontian were : 



Firft, That it was fpecifically lighter than native carbonate o^ barytes (witherite) ; 



Secondly, 



Muriate of barytes affords by evaporation flattened oftagonal cryftals, two of whofc oppojitc fides arc .ilways 

 tniich longer than the others : muriate ef ftrontian, by r.ipidly cooling, cryftallizes in elongated filaments, aad, 

 Tvhen (lowly cooled, in hexagonal columns, of which three fides arc alternately wider, and the otlicrs narrower, 

 and terminated in obtufc triangular pyramids. Thus, though the carbonate of ftrontian much rcfcmbles that 

 of barytes, thefc two lubflances have very different qualities. It is probable that the flfontian mineral has for 

 its bafis a new fpecies of earth which has not hitherto been enamined, and which it is of importance not to fub« 

 ftitutc for barytes for medical ufes. Exiradfrom Dr. Crawford's Dijfexlution. P. 



The above it a tranllation of Citizen Ptlletier't note. Not having Dr. Crawford's frafl on the terra fnnJcrofa 

 Jaliia,ct muriate of barytes, at prefcnt by mc, Ihavc not been able to examine the accuracy of the quotation, but 

 have DO rcafoD to doubt jt, except that I think he ufcs a dilTerenc nomenclature. T. 



