No other animal is so useful in building up good topsoil.It is estimated that in one year fifty thousand earthworms carry about eighteen tons of fine soil to the surface of an acre of land.One worm may add three quarters of a pound of earth to tho topsoil.
帮助改良土壤的蚯蚓
蚯蚓是一种有益的动物。来到地面上,它成了其他动物的食品,而在地里,它却为田地和花园制造着肥沃的土壤。
蚯蚓挖掘风洞,使土壤变松,并使空气和水容易抵达植物的根部。这些风洞有助于土壤迅速排水。
蚯蚓把枯树叶、草和花朵拖进自己的洞中,这种植物性物质腐烂后,便使土壤变得更肥沃了。
在制造优良的表面土壤方面,没有别的动物能像蚯蚓这样有用。据估计,一年中,5万条蚯蚓能把大约18吨的细壤送到1英亩土地的表面,一条蚯蚓也许能把3/4磅的土壤加到地表层。
From Land Animal to King of the Sea
Whales-or their ancestors-were once land animals.Scientists believe that they roamed the earth about 150 million years ago.
The land welling ancestors of this modern king of the sea were hunters with legs and the jaws and teeth of killers.Their favorite hunting grounds were probably shallow waters near the mouths of rivers or off a level stretch of coast,for fish,both finny and shell,were then more plentiful and easier to catch than animals.Because of this,these land mammals came to spend more and more time in the water.
Ages passed,and these creatures swam more easily than they walked;millions of years later they were able to do without legs altogether.They were now recognizable as whales.Their forelegs had turned into the flippers that today,s whales use for steering;their hind legs had shrunk so that mere traces of them can be found under the skin when a whale is dissected.
从陆上动物到海中之王
鲸——或者说鲸的祖先——曾经是陆地上的动物。科学家们认为,大约在1.5亿年以前,它们曾在陆地上转悠。
这个现代海中之王的陆上祖先,是有腿、有颚、有利齿的猎手。它们最喜欢的狩猎场,是靠近河口或是平坦海岸的近海浅水区,因为当时有鳍的鱼类和贝壳类动物比现在要多,而且比其他动物更容易捕捉。由于这一缘故,这些陆地上的哺乳动物便逐渐在水中呆得越来越长了。
几千几万年过去了,这些动物在水里游起来比在陆地上行走更加悠然自得;几百万年以后,它们便压根儿不需要腿了,这时就可辨认出它们是鲸了。它们的前腿变成鳍状肢,今天的鲸鱼便是用它来掌握方向的;它们的后腿萎缩了,因而只有当鲸鱼被解剖时,才能在皮肤下见到后腿的一些痕迹。
Growing Plants Know Right from Left
Plants seem to know which way is up and which way is down;furthermore,they seem to know right from left.If a cutting from a Lombardy poplaris kept alive,new shoots will grow from the end that grew uppermost in the tree.
There is no visible difference between the top and the bottom of the living stick,even under a microscope.Even so,the stick will not send out shoots from the end it views as bottom even if this end happens to be on top!
Scientists,studying this subject further split their cuttings lengthwise.To their surprise,they made another interesting discovery.A good many more buds grew on the righthand side of the split surface than on the left.They split the sticks again and found that the buds again grew on the right side.
The results of the entire study showed a 60-40 preference for the right side,proving that growing plants are basically “righthanded”.
生长中的植物能分辨左右
植物似乎知道哪边朝上,哪边朝下;而且,它们似乎还能分辨左右。从伦巴第白杨上砍下的一根枝条如果还活着,原来长在树的最高处的那一端便会抽出新芽。
这根活枝条的顶部与底部并无明显差别,即便在显微镜下看也是如此。尽管这样,枝条却不从显微镜观察是底部的那一端抽芽,即使这一端碰巧朝上。
研究这一课题的科学家们进一步把他们砍下的枝条纵向切开,使他们惊讶的是,他们又获得另一项有趣的发现。切口表面右侧长出的嫩芽比左侧多得多,他们把枝条再切开,发现嫩芽还是长在右侧。
全部研究的结果表明,植物爱偏向右边,向左偏的只占40%,而向左偏的却占60%。这证明了生长中的植物基本上是“右撇子”。
Hancock,s Signature
Because he wrote his name so that it could be read easily,John Hancock has a place in the dictionary.
John Hancock was a wealthy man who helped the patriots in the American Revolution.He was president of the Continental Congress.He was also governor of Massachusetts and one of the first men to sign the Declaration of Independence.Yet he is remembered best for his large signature.
The story is told that when Hancock sat down to sign the Declaration of Independence,he said that he would write his signature large enough for John Bull to read without his glasses.(John Bull stands for England,as Uncle Sam stands for the United States.)Hancock,s signature on the Declaration is four and threequarters inches long-an inch longer than his usual signature.
Today John Hancock can be used to mean any person,s signature.
汉考克的签字
由于约翰·汉考克把他的名字写得易于辨认,所以他在词典中得以占据一个位置。
约翰·汉考克是一位富翁,在美国革命中曾帮助过爱国者。他是大陆会议的主席,也是马萨诸塞州的州长,是首批在独立宣言上签名的人之一。然而,他主要还是因他那硕大的签名而为人们所铭记。
传说当汉考克坐下来在独立宣言上签名时,他说他要把名字写得很大,以便让“约翰牛”不戴眼镜就看得清楚(约翰牛指英国,如同山姆大叔指美国一样)。
约翰·汉考克在独立宣言上的签名有4.75英寸长——比他通常的签名长了1英寸。
今天,“约翰·汉考克”可以用来指任何人的签名。
How a Hunter Captures a Monkey
Few animals other than monkeys have hand like paws.The monkey,like man,has an opposable thumb-that is,it can place its thumb opposite its other fingers.By pressing its first finger against its thumb a monkey can pick up things as tiny as a flea.Because other animals lack this thumb,it is difficult for them to pick up small things and carry them.
The monkey,s ability to grasp rice with its paw often leads to its capture.Hunters bait a coconut with a handful of rice,leaving a hole in the shell of the nut.The monkey has no trouble sliding its paw through the hole.But it can,t draw the paw out while it is holding a fistful of rice.
Since it is often too stupid or greedy to open its hand,the monkey is unable to free itself from this simple trap.
猎人是怎样逮住猴子的
除了猴子以外,极少有动物长着像人的手一样的爪子。像人类一样,猴子长着可与其他手指相对的大拇指——就是说,它可以把大拇指放到其他几个手指的对面。用其第一指压其拇指,猴子便可拾起像跳蚤一样小的东西。由于其他动物缺少这个大拇指,它们便很难拾起小的东西并把它们带走。
猴子用爪子抓米的本领常导致自己被擒。猎人们在一个椰子里放上一把米作为诱饵,在椰壳上留一个洞口。猴子偷偷地把爪子伸进洞去是没有什么困难的。但它抓满一把米后,爪子却抽不出来了。
由于猴子常常太愚蠢或贪婪得不肯把手张开,它便逃脱不了这一简单的陷阱。
How Americans Showed Their Respect for Edison
Thomas Alva Edison was awarded more patents on inventions than any other American.When he died in 1931,Americans wondered how they could best show their respect for him.
One suggestion was that the nation observe a minute or two of total blackout.All electric power would be shut off in homes,streets,and factories.
Perhaps this suggested plan made Americans realize fully what Edison and his inventions meant to them.Electric power was too important to the country.Shutting if off for even a short time would have led to complete confusion.A blackout was out of the question.
On the day of Edison,s funeral,many people silently dimmed their lights.In this way they honored the man who had done more than anyone else to put the great force of electricity at his countrymen,s fingertips.
美国人怎样表达他们对爱迪生的敬意
托马斯·阿尔瓦·爱迪生获得的发明专利,超过了任何一位美国人。当他1931年离世时,美国人简直不知道究竟怎样才能最充分地表达对他的敬意。