英文科學(xué)讀本 第一冊(cè)·Lesson 32 Coal Ⅰ

Lesson 32 Coal Ⅰ

I have been thinking over our chat about things that burn, said Norah. "Why, Fred, we left out coal, and we all know coal is a good thing to burn. We use it to make our fires."

Yes, sister, said Fred. "We use coal for fuel, to make our fires. But teacher says there is so much to learn about coal, that we must take it by itself."

Go and get a piece of coal, Willie. We will find out all we can about it.

Now, Norah, he went on, "take the coal in your hand. What can you learn by looking at it?"

It is black and shiny, said Norah. "It looks like a lump of smooth, shiny hard, black stone."

Quite right, said Fred. "Now hit the coal with this hammer, and you will see that it easily breaks up into pieces."

So it does. said his sister. "It is brittle, as well as hard."

Now look at your hands, you dirty girl.

Oh dear, said Norah, "the dirty coal has made me quite black. The black comes off on my hands."

Fred next took the piece of coal up with the tongs, and held it in the flame of the fire. It soon caught fire, and burst out in a bright flame.

That's just what I meant, Fred, said Norah. "Coal is one of the best things to burn. It burns till it is all gone. It gives out great heat while it burns."

Yes, said Fred, "that is why we use it for fuel."

I should like to know where we get coal from, said Norah.

Well then, said Fred, "I'll soon tell you. Coal is a mineral, like stone, chalk, marble, rock-salt, clay, sand, and gravel. It is dug out of the ground."

Men dig great deep holes in the ground to get the coal, he added. "We call the holes mines. The men who dig the mines are called miners."

SUMMARY

Coal is dug out of the ground, like stone, clay, chalk, and rock-salt. We call it a mineral; the great deep hole in the earth, where the men dig it up, is a mine; the men who dig it are miners. We use coal for fuel, because it burns well, and gives out great heat.