That is not geography; if s arithmetic.  这不是地理，是算术。

If you want to use big words for around and through, as they do in geographies,  如果你想用大词来表达一圈和深度，就像人们通常在地理上用的那些词一样，

you must say circumference for around and diameter for through一which mean the same thing:  那么你必须用周长来表达一圈，用直径来表达深度—它们的意思实际上是一样的：

the circumference of the World is twenty-five thousand and the diameter is eight thousand. 世界的周长是二万五千英里，直径是八千英里。

The outside of the World is a crust of rock like the skin of a baked potato over the hot inside.  世界的外层是个岩石的外壳，就像烤土豆的外皮，包裹着滚烫的芯。

Some of the crust that you go through first is in layers, like layers in a jelly- cake, one layer after another,  你最先穿过的外壳部分是分层的，像果冻蛋糕里的分层一样，一层又一层，

only these rock layers look as if they were made of sand and shells, or coal or little stones, and that's what they are made of.  只是这些岩石层看起来像是沙子和贝壳，或是煤炭或小石块做成的，事实也确实如此。

If you could cut the World in half as if it were an apple, it might look something like the picture on the next page.  如果可以把世界像切苹果那样切成两半，它也许看起来就会像下一页图片上显示的那样。

We call it a Cross Section. 我们把它叫做剖面图。

Between some of the layers of rock there is coal like jelly in a jelly-cake and in other places there are gold and silver and diamonds and rubies,  在有些岩石层中间有煤炭，像是果冻蛋糕中的果冻一样；其他地方有金、银、钻石和红宝石，

and in some of the rock there are pools of oil.  有的岩石中还有石油层。

That's why men dig wells down through these layers of rock to get oil, and that's why men dig mines to get coal and gold. 这就是人们为了获取石油向地下挖井，穿透这些岩石层的原因，也就是人们为了得到煤和金才开矿的原因。

And still farther down the rock is not in layers—it is just solid rock;  岩石下更深处就不是分层的了—全是坚硬的岩石；

and still farther down it gets hotter and hotter where the world has not cooled off even yet, until the rock is no longer solid, but melted. 再向下更深处越来越热，那是世界甚至到现在还没完全冷却的地方，直到岩石不是坚硬的，而是熔化了的。

Whenever you see a chimney you know there is a furnace beneath it, and when smoke and fire come out of its top you know there is a fire in the furnace.  每次看到烟囱，你就知道下面肯定有个火炉；当烟囱顶部冒出烟和火的时候，你知道火炉里有火在烧。

Well, there are many places on the World where fire and smoke come out of the ground as if through a chimney from a fiery furnace.  嗯，世界上有很多地方冒出火和烟，就像燃烧的火炉里的火和烟从烟囱冒出来一样，

These places are called volcanoes.  这些地方叫做火山。

Why was the World made of rock instead of brass or glass or china?  为什么世界是岩石做的，而不是黄铜、玻璃或者陶器的呢？

Why is the World shaped like a ball and not like a box, a roller, or an old shoe? 为什么世界是球形，而不像一个盒子、像一个滚筒或者像一只旧鞋子呢？