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[ 5 ] EXPERIMENT II. 4. Mineral fubftances that will not diftblve in diftilled water, either entirely or partly, as in Experiment I. may be boiled in oil of olives or linfeed; and if they difiolve therein, entirely or partly, they are of a bituminous nature, or bitumens or mineral inflammables. 5. To afcertain farther the experiment, the fub ftances ought to be thrown on live coals; and if they burn there without any addition, and afFe6t the fmell during the operation, either with agreeable balfamic or often difagreeable effluvia, the inference is eafily made, that they are bituminous. EXPERIMENT III. , 6. Mineral fubftances which, when brought into the fire, will at laft yield, after a violent degree of heat *, by eliquation, a fhining, fomewhat more or lefs du&ile, ponderous fubftance, which may be decompounded in a long-continued fire, or by the addition of an acid; and may again, by adding an inflammable, be reftored to its * Though it is not eafy to give that degree of heat, without fome chemical apparatus, wtiich will be fufficient to melt the me tals out of their refpeftive ores, I however found it neceflary to give this Experiment, as it will be requifite, to get an idea of the charafteriftic of metals.—The charatters, therefore, given, No. 8, of metallic fubftances, though not fo fcientific and perfeft' as I could wiih, will however be fufficient to clafs the mineral bodies by. It is impoffible to give fuch general and exatt charafters of die claffes, that a perfon (houid never be at a lofs in determining what the fubftances under examination really are. It is enough to have pointed out a method by which lie may as nearly as poflible determine and clafs the fubftances; and there will be but few inftances where the application of the rules here prefcribed will not be fufficient. B 3 former