书城教材教辅科学读本(英文原版)(套装1-6册)
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第144章 第二册(61)

"Quite right," said Fred. "It is almost as easy to weld wrought iron together, when it is red-hot and pliable, as it is to join two pieces of clay or putty.

"Wrought iron can be made into any kind of article with the help of the forge, hammer, and anvil. It is malleable, and can be beaten into any shape we please. It is ductile and tough, and can be drawn out into wire of any thickness.

"Its immense strength renders it just the thing for making girders, or beams for bridges, and arches, and great buildings. It is used for making steam engines, which have to do all sorts of work. Chains, too, of all kinds are made of wrought iron, because wrought iron will bear any amount of tugging and straining without giving way."SUMMARY

Wrought iron is tough, flexible, malleable, and ductile. When it is made red-hot in the furnace, it becomes pliable; it can then be welded at the anvil. Wrought iron will bear any amount of tugging and straining. Chains, bridges, arches, and engines are made of it.

Lesson 28

The Horse

"We are going to talk about the horse," said Fred. we will all go into the stable, and have a look at our dear old Tommy-the best horse in the world.