APPENDIX. 



*45 



cryftals readily, which, when mod regular, are oclohsedral, 

 confifting of two quadrangular pyramids, united at their bafes. 

 They efflorefce in a dry atmofphere, in a moid they deliquefce. 

 One ounce of diftilled water, at temperature 60, diflblves an e- 

 qual weight of this nitrate of Strontites ', when boiling, one 

 ounce, feven drachms fourteen grains. It deflagrates on hot 

 coals. Subjected to heat in a crucible, it decrepitates gently, 

 melts and boiling lofes its acid. The contact of a combuflible 

 body at this time caufes a deflagration, with a beautiful vivid 

 red flame. 



Muriatic acid aflaults the Strontian mineral in a manner very 

 fimilar to the nitric. The folution is free from colour, has a pe- 

 netrating peculiar tafte, and affords cryftals freely. Thefe are 

 long flender fpiculae or hexagonal prifms. Muriate of Stron- 

 tites, in a very moifl air, fhows a difpofition to attract humidi- 

 ty, contains 42 per cent, of water, and when heated, firft un- 

 dergoes the aqueous, then a true fufion, but without lofs of 

 acid, which may be expelled by a more vehement heat. One 

 ounce of diftilled water, at temperature 60, diflblved twelve 

 drachms, one fcruple ; when boiling above four ounces. 



Strontites, and all its combinations, poflefs the remarkable 

 property of tinging flame of a red colour. The muriate has it in 

 the moft eminent degree, and its effects are well exhibited by put- 

 ting a portion of the fait on the wick of a candle, which is 

 thereby made to burn with a very beautiful blood red flame. 

 The nitrate ftands next, then cryftallized Strontites, and after it 

 the acetite. The following combinations of little folubility 

 give comparatively a very feeble tinge : Tartrite, fulphate, ox- 

 alate, fluate, arfenicate, carbonate, phofphate, and borate. The 

 order of enumeration denotes their relative tinging powers. 



A certain portion of humidity, either belonging to the 

 compofition or added, is necefTary to enable any of thefe Stron- 

 titic falts to alter the hue of the flame. The muriate itfelf, de- 

 prived of moifture, produces no effect. 



Vol. III. ' (T) All 



