y found in the ground in a pure state. for the most part they are combined with oxygen or sulphur. such was the case with the two specimens which cyrus harding had brought back， one of magnetic iron， not carbonated， the other a pyrite， also called sulphuret of iron. it was， therefore the first， the oxide of iron， which they must reduce with coal， that is to say， get rid of the oxygen， to obtain it in a pure state. this reduction is made by subjecting the ore with coal to a high temperature， eith
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