英國學(xué)生科學(xué)讀本 Lesson 4 黑鉛
第四課 黑鉛
What is the black-lead in your pencil made of? If you take a bit of the metal which we call lead, you will find that it is grey in colour, very heavy, and not at all like the black-lead in your pencil. But the lead will make a mark on paper just as your pencil does.
小朋友，你鉛筆里的鉛芯是什么做的?拿一塊兒叫"鉛"的金屬看看，鉛是黑色的，特別重，跟鉛芯一點兒也不一樣。但 是鉛也會在紙上留下印子，跟鉛筆一樣。
We call the stuff black-lead, because it makes marks like lead; but there is really no lead in it at all. Black-lead is not a metal. It is made of carbon, which is also found in coal and in many other things. It is the carbon in coal which makes it burn so well.
我們把鉛芯里的東西叫石墨，就是"黑鉛"的意思。這是因為，它在紙上也能像鉛一樣留下印子;但其實，鉛芯里一點兒鉛都沒有。石墨是碳做的，煤里，就有碳，好多別的東西里也有碳。煤里正是有了碳，才會這么容易燃燒的。
If we make black-lead very hot, it will burn. But it will burn very slowly-so slowly that it would be of no use for making a fire.
如果把石墨弄得特別熱，石墨就會燃燒起來，但是燃燒得特別慢，不能用它生火。
Black-lead is found in some kinds of rocks in big lumps. These lumps are ground into very fine powder, and then the powder is pressed into hard blocks.
有一些石頭里面會有大塊的石墨。人們把這些大塊石墨，先磨成細粉，又壓成硬塊兒。
These blocks are next cut up into thin strips. Each strip of black-lead is made of just the right size to fit into the hollow that has been cut for it in the wood of the pencil.
這些硬塊兒，最后又切成了細條。同時，在鉛筆的木頭上，也切出來了凹槽。每一根石墨的細條，大小都正好放進凹槽里面。
Your mother will tell you that black-lead is very useful to her in the house. She rubs it on stoves and grates, and many other things that are made of iron, to cover the iron and keep it from rusting.
小朋友，你的媽媽會告訴你，石墨在你家里也非常有用!媽媽把石墨涂在爐子、爐柵上面，涂在很多鐵器上面，把鐵蓋起來，這樣它們就不會生銹了。
The damp air makes the iron rust; but when we cover it with black-lead, the air cannot reach it, and it keeps bright.
潮濕的空氣會讓鐵生銹，但是只要用石墨蓋住，鐵就接觸不到空氣，會一直亮閃閃的。
Have you ever seen a diamond? It is a very bright, hard kind of stone, and very dear. Diamonds are sometimes set in gold rings, and they are very pretty. Yet the diamond is made of pure carbon, just as black-lead is.
小朋友，你見過鉆石嗎?鉆石，也叫金剛石，是一種非常光亮，非常堅硬的石頭，價錢還特別貴。有些鉆石嵌在金戒指上，漂亮極了。可是，鉆石卻是純碳做的，就跟石墨一樣!
Is it not strange that the dull black-lead, which costs so little, and the sparkling diamond, which costs so much, are both made of the same stuff that burns in the grate to keep us warm?
黑黑的石墨那么便宜，亮晶晶的鉆石那么貴，這兩種東西，卻跟那燒在爐子里讓我們?nèi)∨拿?，都是一樣的東西做的，好奇怪呀!
