1.Look at your slate，and see what it is made of.It is a very thin，smooth，grey stone.The pencil with which you write upon it is also a piece of soft slate.
2.When you rub the soft slate-pencil upon the slate，many little pieces of the pencil are broken off.These tiny pieces form the white marks which you see when you write.They do not stick to the slate，but can easily be rubbed off with a wet sponge.
3.The slate is not at all like the lump of putty which we made.The putty was soft；we could press it into any shape we pleased.But the slate is hard.However much we squeeze it，we cannot change its shape.
4.The putty did not break when it fell to the ground；but if we drop a slate，it will break.So we say that the slate is brittle；it snaps or breaks easily.
5.Like all solids，slate keeps its shape，and it keeps its size too.You cannot change a little slate into a big one，however hard you pull at it to try to stretch it.
6.Pieces of slate are put on the roofs of houses，to keep out the rain.Water cannot pass through slate.The slater makes two little holes in each slate，and then nails them on to the roof.
7.But where do slates come from？If you ever go to Wales，or to Cornwall，or to Scotland，youmay see great holes in the hill-sides-“quarries，”the men call them-where all the rock or stone is nothing but slate.
A SLATE QUABRY（板石的采石场）
8.Some men break off great lumps of the rock，and then other men split these lumps into the thin pieces we call slates.We can tell slate from all other rocks by the way it splits into very thin layers.
9.Scr ape some slate-pencil into a glass of water.The water looks muddy.The slate itself was once mud at the bottom of the sea.That was a very long time ago；and the slate has been so squeezed and heated inside the earth since then，that it has become hard and stony.
10.We often find pieces of slate like the one in the picture，full of marks of the shells or of the fishes that lived in the sea long ago.When these creatures died，they sank to the bottom，and were buried in the mud.
SUMMARY
Slate is a very thin，smooth，grey stone.It is very brittle.It is got out of great holes，called quarries，in the hill-sides.Large lumps are broken off the rock，and then split into thin pieces.Slate-pencils are made from a soft slate.Roofs of houses are made of slate.Slate is formed from mud which has been changed by being pressed and heated inside the earth.
【中文阅读】
1．小朋友，看看你自己写字用的石板，了解一下它是什么做的？这是一块非常薄、非常光滑的灰色石头。你在板石上写字的笔，也是一块比较软的石头，叫做板石。①2．把软的板石笔在板石上蹭蹭，就会有很多板石笔的碎片掉下来。这些碎片就变成了你写字的时候看见的白印子。这些白印子不是黏在板石上的，用湿海绵很容易就能擦掉。
3．板石，跟我们以前做过的腻子块儿，一点也不像。腻子是很软的，我们想要什么形状，就可以把它捏成什么形状。可是板石很硬，不管怎么使劲儿地挤，都不能改变它的形状。
4．腻子块儿掉在地上是不会碎的，可要是把一块板石掉到地上就会摔碎。所以我们说，板石很“脆”，很容易就能折断、打碎。脆的英语叫brittle.
5．跟所有的固体一样，板石有固定的形状，也有固定的大小。不管怎么拉它，拽它，都不能把一块小板石变成一块大板石。
6．板石片也放在屋顶上，用来挡雨。水是透不过板石的。装板石的工人在每一块板石上钻出两个洞，用钉子把板石固定在屋顶上。
7．板石是怎么来的呢？如果你去一趟威尔士、康沃尔郡，或者苏格兰，你可能会在山坡上看见一些大洞，人们管这种大洞叫“采石场”，英语叫quarry.在这些地方，所有的石头全是板石。②8．一些人把板石块开采出来，然后另一些人，把这些大石块分成我们叫“板石”的细片。板石跟其他石头的不同，就在于它能分成非常薄的石片。
9．把板石笔擦一些碎屑下来，让碎屑落进一杯水里，水看上去就成了泥浆。很久很久以前，板石就曾经是海底的泥，后来在地球内部被挤压、加热，最后变成了硬硬的石头。
10．我们经常会找到这张图上这样的石头，上面有很多远古生活在海里的贝壳或者鱼类的印迹。这些动物是在死掉之后，沉到海底，被埋在泥中的。
译注
①看到这儿读者可能要问了，石板是什么？我写字没用过这个东西啊？原来，100年前，写字的纸比现在要贵，小学生们为了练习写字和算术，需要一种比纸更耐用、更便宜的东西，所以他们人人都带着一块小黑板。这种黑板是一种叫板石（也叫黑板石、板岩）的石头做的，一般是墨绿色的，英国小学生当时用的石板，大概有12厘米长，9厘米宽。中国作家魏巍写过一篇《我的老师》，里面提到，老师有一次假装用教鞭打他，“我用石板一迎，教鞭轻轻地敲在石板边上”，这种石板，就是课文里说的东西。但是这本书出版之后不久，石板在欧美就被淘汰了。中国因为经济发展水平的原因，有些地区直到60年代还在用。读者的爷爷奶奶在小时候可能还用过呢。板石笔的作用跟粉笔差不多，但是写的字比粉笔细得多，而且不容易蹭掉。板石除了做黑板，还能做建筑材料。中国出产板石的地方，主要是陕西、四川、湖北一带。
②英国的全名叫“大不列颠和北爱尔兰联合王国”，分成英格兰（England）、威尔士（Wales）、苏格兰（Scotland）、北爱尔兰（North Ireland）四个王国；康沃尔郡（Cornwall）是英格兰西南部的一个郡。威尔士、苏格兰、康沃尔郡都是板石的出产地。
AN EAR OF WHEAT