英国学生科学读本 Lesson 32 一块软木(1)
第32课 一块软木
Corks are so cheap and so common, that every child who reads this Lesson can get a cork to handle and to look at. Let us try with a pen-holder to keep a cork down at the bottom of a glass of water. It is very hard todo this; for the cork is very much lighter than its bulk of water, and so it is always trying to rise to thetop.
软木很便宜, 很常见。读到这一课的小朋友, 人人都可以把一块软木塞拿在手上, 好好看看。咱们试试, 用一支笔杆子把软木塞按到一杯水底下。很难把软木塞按住, 因为软木塞比它这么大体积的水轻得多, 所以总是要往水面上浮。
Men who go out in life-boats wear canvasbelts filled with pieces of cork. If the boat should be upset, the cork is so light that it would help the men to float , and save them from drowning.
救生艇上的救生员, 都穿着一种帆布带子, 里面盛满了软木块儿。要是船万一翻了, 软木非常轻, 可以让人浮起来, 不让人淹死。
Squeeze a cork between your fingers. You can easily compress it, or make it smaller. But when you take your fingers away, the cork springs out to its old size and shape. Things that do this are called elastic.
用两个手指挤一下软木, 可以很容易地压缩这块软木, 让它变小。可是, 一放开手指, 软木就弹回了原来的大小和形状。有这种性质的东西叫做“弹性物体”。
Because cork is elastic, it makes good stoppers for bottles. The cork ought to be just a little larger than the neck of the bottle. We force the cork into the neck of the bottle, and it presses against the sides of it, and fits it exactly.
因为软木是有弹性的, 所以很适合做瓶塞子。软木塞应该只比瓶颈大一点儿, 我们把软木塞用力塞到瓶颈里面, 软木塞就挤在了瓶颈的壁上, 尺寸刚刚好。
But what is cork? Cork is the outer bark of a kind of oak-tree, which grows in the south of Europe. It is an evergreen oak— that is, it is always covered with green leaves. It grows to a height of thirty or forty feet.
但是, 软木究竟是什么东西呢? 软木是一种栎树的树皮, 这种树长在欧洲南部, 是一种常绿乔木, 也就是一直长着绿叶子的树, 能长到30–40英尺高。
