APPENDIX. 147 
_ STRONTITEs and its compounds tinge flame, which barytes 
does not... Laftly, thefe earths difagree in the order of their 
attractions. 
From thefe confiderations, it is concluded, that the mineral - 
is not aérated barytes. 
Sometimes the Strontian foflil refembles calcareous fpar ; yet 
they eflentially differ in property and compofition. That from 
Strontian is much heavier, and retains its fixed air with more 
obftinacy in the fire. The incomparably greater folubility of 
the pure earth in hot than in cold water, and the cryftalline 
form it afflumes, fufficiently diftinguifh it from lime, which the 
difpofition of the nitrate and muriate to cryftallize, no lefs tends. 
to do. 2 
Tue quality of colouring flame does not ferve here as a cir- 
cumftance of difcrimination, as Dr Hope has difcovered, that 
muriate of lime alfo tinges the flame of a red colour, but in a 
‘lefs vivid manner. Strontites further differs from lime in the 
order of its attractions. . 
No parallel is drawn between Strontian mineral and other 
earthy bodies, as they have not the f{malleft refemblance. 
As the earthy bafis of the Strontian fpar poffeffes remarka- 
ble qualities, that are peculiar to it, and forms with acids com- 
binations unlike thofe generated by the known earths, and dif- 
fers from all of them in the order of its attra¢tions, the author 
of the paper concludes, that it is an earth /wi generis, a feparate 
and diftin& genus, conftituting the fixth fimple earth, to which, 
_ as above mentioned, ‘he gives the appellation of Strontites. 
Dr Hope afterwards details a long train of experiments to. 
_ eftablith the order of the attraétions of this new earth; firft,. 
determining the order in which the principal acids attra@ it, 
and then fhowing the place due to its attra¢tion among thofe 
of other fubftances for acids. The tables that are fubjoined ex- 
hibit thefe attractions 
Dr 
