Iron

   Iron is a hard, heavy, well known metal. Pure iron is silvery-white in color, but it is seldom seen. Wrought iron is the purest commercial form; yet piano strings, the purest wrought iron in the market, contain three pounds to the thousand of carbon and other elements. When in the presence of a magnet, or when placed with-in a coil through which an electric current is passing, soft iron becomes magnetic. Iron remains unchanged in dry air, but rusts —unites with oxygen—in moist air.
   Iron is the most useful of all metals, and of all metals it is the most widely distributed in nature. It forms a twentieth part of the world's crust. It is essential to life of all sorts. It is found in the green chlorophyll of plants and in the blood of ani¬mals. It occurs in meteorites. The color spectrum shows that iron is present in the Sun. There is an iron mountain near Durango, Mexico. It is a projecting back-bone or dike of solid iron ore,—a huge mass one mile long, a third of a mile wide, and 450 to 650 feet high. Similar hills in Missouri are known as Iron Mountain and Pilot Knob.

Iron meteorite