SUBJECTS saline principle

In the same paper, Geoffroy also cautiously breached another subject of inquiry the composition of iron. He offered a conjecture that iron, like sulphur, might also be a compound of the sulphur principle or an inflammable part, a vitriolic salt, and an earth. " Common sulphur and iron would differ then only in the earth they contained, sharing two other common constituents. The facility with which iron was inflamed showed that it was sulphurous. The rust of iron, or the dissolution of iron by the humidity of air, indicated that iron was saline and vitriolic. In addition, Geoffroy produced a more philosophical proof by recomposing iron, the black, heavy powder attracted by the magnet, from the three named constituents ... 

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