"There was a gallery all round the top, and we could see the men on the gallery wheeling barrows filled with iron-stone and fuel. The furnace is always fed from the top. Every half hour the men throw in their barrow-loads of iron-ore, coke, and lime. The furnace burns day and night, and is never once allowed to go out for years.""I suppose the great heat melts the iron in the ore," said Norah, "for iron is fusible.""Quite right, little sister," said Fred, "and the melted iron sinks to the bottom of the furnace, because it is heavier than the other substances."SUMMARY
Iron is the " king of metals." Iron-stone or iron-ore is dug out of the earth. It is ?rst mixed with coal, and roasted in great heaps. Then it is smelted in the blast furnace with coal, coke, and lime. The enormous heat melts the iron of the ore, and it sinks to the bottom of the furnace as a thick, red-hot liquid. All the useless parts of the ore ?oat on the top of the liquid iron.
Lesson 23
Iron