英國學(xué)生科學(xué)讀本 Lesson 39 柔韌的軟金屬-鉛(1)

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2020年02月23日

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Lesson 39 A Soft And Flexible Metal—Lead

第39課柔韌的軟金屬——鉛

In Wales, in Derbyshire, and in the north of England, hills made of limestone are very common. In the cracks of this limestone we often find a beautiful silvery mineral called galena. It is made of lead mixed with sulphur.

在威爾士王國、在德比郡、在英格蘭的北部, 有很多石灰?guī)r構(gòu)成的小山。在石灰?guī)r的縫隙里面, 我們經(jīng)常能夠發(fā)現(xiàn)一種美麗的銀色礦物, 叫做“方鉛礦”, 它是硫和鉛的化合物。

Minerals or stones, like galena, which contain useful metals, are known as ores. To get the lead from it, thisore is first broken down into powder and roasted in a furnaceat a gentle heat. Then the furnace is made hotterand hotter, until the lead melts and runs off.

像方鉛礦這樣, 含著有用的金屬的礦物或者石頭, 我們叫它“礦石”, 英語是ore。要想把鉛從礦石里頭弄出來, 首先要把它碾成粉末, 用不算太高的溫度在熔爐里加熱。然后, 把熔爐燒得越來越熱, 最后鉛就熔化了, 流了出來。

Lead is between blue and grey in colour, so we call it bluish-grey. It is so soft that it can be easily scratched with the thumb nail. If we scrape a piece of lead with a knife, the new surface is bright and shining. Butin a few days it gets dim or rusts by being exposed to the air.

鉛的顏色介于藍(lán)色和灰色之間, 所以叫“藍(lán)灰色”, 英語是bluish-grey。鉛的質(zhì)地特別軟, 用大拇指的指甲就很容易劃出痕跡。如果我們用小刀切下一塊鉛來, 鉛的斷面就是閃閃發(fā)亮的。但是過了幾天, 暴露在空氣中的斷面, 就會暗淡下去, 生銹了。

Men who work with lead are called plumbers. If you watch a plumber at work, you will see how easily he bends the lead pipes, and how cleverly he hammers the sheet-lead with a mallet, and makes it fit into any corner. Because lead bends so easily, we call it a flexible metal.

加工鉛的人叫“管子工”, 要是你見過管子工的工作, 你就會看見他很容易地彎曲鉛管, 巧妙地用木槌, 把鉛皮敲成適合任何角落的形狀。因?yàn)殂U可以很容易地彎曲, 所以它是“柔韌性”很好的金屬。

Lead can be hammered or rolled out into thin sheets.

鉛可以用錘子敲成, 或者壓成薄片兒。