On digging round the mass, the under surface was found covered with a coat of scoriæ from four to six inches thick, undoubtedly occasioned by the moisture of the earth, the upper surface being clean. No appearance of the formation of iron was observed in the earth, below or round it, for a great distance. About two leagues to the eastward was a brackish mineral spring, and a very gentle ascent of from four to six feet in hight, running from north to south: with this exception, the adjacent territory was a perfect level. About the spring, as well as near the mass, the earth was very light, loose, and greatly resembling ashes, even in color. The grass in the vicinity was very short, small, and extremely unpalatable to the cattle; but that at a distance was long, and extremely grateful to them. From these concurrent circumstances it was concluded, that this mass of native iron, which was estimated to weigh about three hundred quintals, was produced by a volcanic explosion. It is stated as an undoubted fact, that in one of the forests of the above district of Santiago del Estero, there exists a mass of pure native iron, in the shape of a tree with its branches. At a little depth in the earth are found stones of quartz, of a beautiful red color, which the honey-gatherers, the only persons who frequent this rude territory, employ as flints to light their fires. Several of these were selected on account of their peculiar beauty, they being spotted and studded, as it were, with gold: one of them, weighing about an ounce, was ground by the governor of the district, who extracted from it a dram of gold. A fibrous kind of native iron has been found at Ebenstock, in Saxony, and also in Siberia, where one particular mass weighed sixteen hundred pounds. It resembled forged iron in its composition, and was malleable when cold, but brittle when red-hot. In Senegal, where it is most common, it is of a cubical form, and is employed by the natives in the manufacture of different kinds of vessels. Native meteoric iron, called also nickeliferous, from its containing nickel, and native steel iron, which has many of the characters of cast steel, have also been found.