5^2 On the AJfajitig of Ores hy Fujiort- 



to it, by the decompofition of water, exceeds 25 per cent. ie\V 

 traces of magnetic attraftion are perceptible:— introduce this 

 oxyde into a covered crucible, without any addition, and 

 expofe it to a violent degree of heat for 40 minutes^ (longer 

 in proportion to the quantity,) a button of highly oxygenated 

 crude iron will be obtained : if the heat is continued longer 

 than is nccellarv to eff'ccl this, a fmall mafs of malleable' 

 iron will be found occupying the bottom of the crucible. 

 The produce in either cafe will be (hort of the real quantity 

 of metal contained in the oxyde. When oxygenated crude 

 iron is obtained, the ore from which it is produced, to life 

 the common phrafeology, is faid to contain bad iron. That 

 this has no relation to truth, will be feen by taking another 

 portion of the fame oxyde; let it be mixed either with chalk 

 or lime, and a little hottle-glafs, to conftitute fufibility, and 

 expofed to a fimilar degree of heat with the former; the 

 whole contents in iron will then be found revived, and oc- 

 cupying the bottom of the crucible in the ftate of fine car- 

 bonated crude iron. Here then is a complete alteration in 

 the quality of the metal, though obtained from the fame ore j 

 for we cannot confider iron combined with oxygen, to which 

 earthy bafcs are given, in any other light than that of an 

 ore. Asrain, let a portion of mixture, exactly fimilar to the 

 laft, have added to it double or triple its weight of bottle 

 glafs, and fubjcft the whole to an equal heat with the for- 

 mer experiments, nearly a complete revival of all the metal 

 will be found to have taken place; its quality, however, will 

 be highly oxygenated and brittle. Such experiments clearly 

 demonftrate, that the various qualities of crude iron are en- 

 tirely owing to the mixtures in the ore, and their treatment^ 

 and that iron, confidcred as a fimple metallic fubftance, is 

 the fame in point of quality in all ores. 



If iron v.-as originally formed in a metallic fiate, its pro- 

 perty of decompoling water, whether cafually expofed to a 

 moift atmofphere, or removed at various depths from the 

 Curface, furnidies an hypolhefis as to the primitive principle 

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