2007-9-2 16:33
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The Last Part of This Century,an Age of Exploration
The last part of this century will be an age of exploration such as man has never known.There are eight planets,at least thirty moons,and thousands of asteroids to be explored.Their total area is about 250 times that of the earth.Space-ships will not be able to land on some of them.But that still leaves to be explored an area ten times as great as the continents of the earth.
Exploring space may seem terrifying to some people.No doubt explorers of the past were terrified by the great empty oceans that lay before them.They conquered their fears,crossed the oceans,and built the New World.
In the past when explorers set sail into the unknown,they had to say good-by to everything they knew at home.Space explorers will not face such great loneliness.Even when they travel far beyond the sun,they will be able to send messages back.
2007-9-2 16:34
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Army Life in the American Civil War
For every man in the Civil War who died in battle,two or three men died of disease.Doctors of that time knew very little about causes of sickness or ways of preventing it.Thousands of men in poor health became soldiers.Hundreds of others had never had childhood diseases.Many of these soldiers could not withstand the epidemics of measles,mumps,and whooping coughthat went through the camps.
Army life was hard.Soldiers got few fruits or vegetables.There was no milk unless they happened to find a cow.Neither their clothes nor their shelters protected the troops from rain,snow,and cold.Sickness and disease were spread by insects,rats,and impuredrinking water.Often the men drank straight from muddy streams.
Gunshot wounds were serious,as in any war,but they did not cause as much death and suffering as disease did.
2007-9-2 16:35
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The Dugout in the Side of a Hill
When the pioneers began their conquest of the western prairie,they found materials for building shelters close at hand.Where timber was availabls,the settlers sometimes built log houses.Most prairie homes,however,were either sodhouses or dugouts.These houses could be built quickly and easily.
The dugout was a room dug in the side of a hill.A few railsor posts were used to make a door frame and,possibly,a window.The front wall was made of pieces of sod or logs.Sloping back onto the hill was a roof made of poles or logs covered with a layer of brush,a layer of prairie grass,and a layer of dirt.
As soon as a covered wagon halted at a new homestead,the head of the family took out his spade.The family lived in the wagon for the few days that it took him to build a dugout.
2007-9-2 16:35
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Time Zonesand the International Date Line
Strange things happen to time when you travel,because the earth is divided into twenty-four time zones,one hour apart.You can have days with more or fewer than twenty-four hours,and weeks with more or fewer than seven days.
If you make a five-day trip across the Atlantic Ocean,Your ship enters a different time zone every day.As you enter each zone,the time changes one hour.Traveling west,you set your clock back;traveling east,you set it ahead.Each day of your trip has either twenty-five or twenty-three hours.
If you travel by ship across the Pacific,you cross the international date line.By agreement,this is the point where a new day begins.When you cross the line,you change your calendar one full day,backward or forward.Traveling east,today becomes yesterday;traveling west,it is tomorrow!
2007-9-2 16:36
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Ballet,a Combination of Four Arts
Although the first thing that comes to mind when we hear the word ballet is a graceful ballerinagliding across the stage,the ballet is not just dancing.The final production is a combination of four arts:dancing,music,drama and painting.It is also a combination of the efforts of many people.
The ballerina and her partner dance the main roles.It may be hard to realize that behind their seemingly effortless movements are long years of practice.She had to dance in minor roles for many years.The premier danseur had to learn the art of partnering,of showing off the ballerina so that she appears to be perfect.
Some of the people who create a ballet never appear on stage.They are responsible for the music to which the dancers move,the theme of the ballet's story,the sets,and the costumes.It is the fusion of these many talents that creates the one,overall effect that is a ballet.
2007-9-2 16:37
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From Land Animal to King of the Sea
Whales——or their ancestors——were once land animals.Scientists believe that they roamed the earth about 150million years ago.
The landd 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.
2007-9-2 16:37
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Columbus that Made Four Voyages to the West
Columbus made four voyages to the west between 1492and 1504 in his vain search for a sea route to Asia.The mystery of why he failed to find it haunted him and filled with sadness.
Wherever he went——to Cuba,Puerto Rico,Jamaica,South America,Panama,down the coast of Central America——it was always the same story.Instead of golden palaces,there were grass huts and palmleaf tents.Instead of silk robed merchant princes,he found “Indians”who did not have so much as a shirt on their backs.
At times Columbus became reconciled to the truth that this new land was not China,not Japan,not the spice Islands.He seemed to accept it as a part of the earth that the geographers of Europe had never heard of before.It was another world——and he called it exactly that——but Columbus also insisted until he died that the land he had reached was an unknown part of Asia.
2007-9-2 16:38
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When People Began to Eat With the Fork
“Fingers were made before forks.”When a person gives up good manners,puts aside knife and fork,and dives into his food,someone is likely to repeat that saying.
The fork was an ancient agricultural tool,but for centuries no one thought of eating with it.Not until the eleventh century,when a young lady from Constantinople brought her fork to Italy,did the custom reach Europe.
By the fifteenth century the use of the fork was wide-spread in Italy.The English explanation was that Italians were averse to eating food touched with fingers,“seeing all men's fingers are not alike clean.”English travelers kept their friends in stitches while describing this ridiculous Italian custom.
Anyone who used a fork to eat with was laughed at in England for the next hundred years.Men who used forks were thought to be sissies,and women who used them were called show-off sand overnice,Not until the late 1600's did using a fork become a common custom.
2007-9-2 16:39
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On the Beaches of Block Island
Doubloons worth a king's ransom may lie buried on Block Island,nine miles off the Rhode Island coast.Many seventeenth century pirates visited there to plunder and to get supplies.
Only a hundred years ago,one story says,a ship anchored off shore one night and sailed out at dawn.Soon after,an island farmer found pieces of eight around a hole in his cornfield.Islanders are sure there is still treasure there.One man even kept“treasure rights”when he sold his property.
“Terrific place to bury treasure,”another islander said.He pointed at the vast expanse of beach and cliffs.“A body could come sneakin' in here at night,bury his loot,and cat-foot it out before anyone knew what was up.”
Probably not only pirates buried loot on the beaches of Block Island.Some early islanders were reputedly ship-wreckers.No one knows how much booty they removed from ships lured by their lanterns to smash on the jagged rocks.
2007-9-2 16:40
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A Cub Reporter,the Important Step towards a Career in Newspaper Reporting
The student who wants a newspaper career has much hard work ahead of him before he can become even a cub,or beginning,reporter.He may begin by working on his high school newspaper or yearbook.
Then the aspiring reporter may break into newspaper work as a copyboy,running errands and helping staff reporters.He may even be given a chance to write small stories.Sometimes students who are interested in news reporting can get jobs as campus reporters for local newspapers.
Jobs such as these serve to acquaint the beginner with the atmosphere of news gathering.They give him a chance to sharpen his eye for details and teach him to be sure that his facts are accurate,that he reports them correctly,and that he writes his articles clearly.This work may lead to a job as a cub reporter on a newspaper,the important first step toward a career in news reporting.
2007-9-2 16:40
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Cookware during the Reign of Edward Ⅲof England
Pots and pans were once considered to be precious possessions.In the fourteenth century,during the reign of Edward Ⅲof England,the pieces of cookware——iron pots,griddles,spits,and frying pans—were numbered among the king's jewels.They were difficult to come by and,being rare,were extremely valuable;when the monarch went on a journey or made a visit,the pots and pans traveled along in a separate coach.
By the time Henry Ⅴ,Edward's grandson,ascended the throne in the following century,the royal frying pans were made of silver,and so were the roasting spits.
The kettles at Westminster during the early sixteenth century,when Henry Ⅷheld the throne,were “coppergilt”and quite lavishly decorated with chasing.The handles of the cooking ladles were chased with the royal arms,and one of the two-pronged toasting forks is known to have been tipped with an ornate metal ball.
2007-9-2 16:41
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A Baboon that Has Learned to Count
Cowboy the batoon has learned to count——at least when he is hungry.Dr.Jack Findley of the University of Mary land has taught him to recognize five colors of lights;each light stands for a certain number of beeps from a sound box.
When Cowboy turns on a light by pushing a button,the box begins making beep tones——the number of beeps.Cow-boy must count is determined by the color of the light.When the correct number has sounded,Cowboy pushes a second button.This stops the sound and releases a food pellet.If he pushes the button too soon or too late,Cowboy doesn't get any food.
Cowboy is required to keep track of only five signals now,but he may have to think harder soon.Dr.Findley plans to shine two lights at once,and to require the baboon to push the button when the correct combined number has sounded.
If Cowboy is able to do this,he will have learned how to add.
2007-9-2 16:42
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The Air-cushioned Vehicle that Travels Clear Out of Sea and Land
The air-cushioned vehicle is not an airplane,since it does not have wings.It is neither a ship nor an automobile,since it travels clear of sea and land.It has a conventional gasoline engine,but no wheels.How does it travel?What keeps it in the air?
Under the air car is an air chamber with a large propeller parallel to the ground.The gasoline engine supplies power that causes the propeller to whirl.This fills the chamber with air.Some of the air is forced toward the ground through tiny holes around the edges of the car.
These air jets create a wall that keeps the air from escaping from the chamber.As more and more air crowds into the chamber,the molecules of air become compressed.Their pressure becomes so strong that it lifts the car off the ground.
2007-9-2 16:43
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America's Dead Sea
Picture a still,shallow lake at the bottom of a huge basin.Long after experts insist it should have dried up,the Great Salt Lake of Utah——America's so-called Dead Sea——still exists.
The supposedly dead lake has no fish,but millions of tiny shrimp and several forms of algae——primitive plant life-thrive there,in waters saltier than the ocean.Gulls roost on is-lands in the lake and shore birds nest in the marshes around it.
Ancient beaches high on the sides of the surrounding mountains show that the lake once covered more than twenty times its present area.Other evidence shows that the lake has completely dried up several times in its history.
The lake's level has not dropped much in the last hundred years,despite increased use of water from its sources for irrigation.Current plans for diverting the large Green River into the basin around the lake may even increase the lake's present size.
2007-9-2 16:44
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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 right-hand 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 “right-handed”.
2007-9-2 16:45
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The Badger,a Courageous Fighter
The badger has been nicknamed“doormat”because of its broad,squat form and its hairy back.Actually it is a courageous fighter.In pioneer days it was considered great sport to turn a pack of dogs loose on this furry foe,but few dogs were willing to challenge the badger a second time.
When attacked,the badger digs a protective hole;if cornered,it releases a strong odor from glands near its tail.The badger's height——only about nine inches——places its throat below the line of attack of most dogs,and the back of its neck is protected by coarse hair.
In a fight,the badger's front claws are for midable weapons.It can leave a dog limping after one well-placed bite of its sharp teeth.Only the low-slung dachshund can easily get a deadly throat hold on the badger;this dog was once much used in“badgering”.Fortunately for the badger,the popularity of this sport has decreased considerably.
2007-9-2 16:45
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The Shooting of a British Pig that Almost Started a War
“Charlie Griffin's British pig was in my potatoes again!”bellowed Lyman Cutler one day in 1859.The next time the pig snuffled into Cutler's potato patch,he shot it.The pig's owner swore to have Cutler jailed,and this almost started a war.
At that time San Juan Island,where both men lived,was claimed by both the United States and Britain.When word reached the United States that the British were going to try an American for shooting a pig,U.S.troops were dispatched to Puget Sound.The British,in turn,sent warships.The Americans then sent more troops.
U.S.General Winfield Scott talked the matter over with the British governor;national honor was now involved.The general and the governor agreed to occupy the island together,and the troops returned home without any arrest being made.
The dispute was finally settled in 1872,when San Juan Island was awarded to the United States.
2007-9-2 16:46
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The Patient and the Ship Owner
This incident occurred one morning outside Albert Sch-weitzer's hospital in the African jungle.A patient had gone fishing in another man's boat.The owner of the boat thought he should be given all the fish that were caught.Dr.Sch-weitzer said to the boat owner:
“You are right because the other man ought to have asked permission to use your boat.But you are wrong because you are careless and lazy.You merely twisted the chain of your canoe round a palm tree instead of fastening it with a padlock.Of laziness you are guilty because you were asleep in your hut on this moonlit night instead of making use of the good opportunity for fishing.”
He turned to the patient:“But you were in the wrong when you took the boat without asking the owner's permission.You were in the right because you were not so lazy as he was and you did not want to let the moonlit night go by without making some use of it.”
Dr.Schweitzer divided the catch among the fisherman,the boat owner,and the hospital.
2007-9-2 16:47
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The United States in about 23 Million Years
The ordinary raindrop is a mighty earth mover with sufficient strength to cut rock.When rainwater collects on the surface of the ground,some of it evaporates and some of it sinks into the earth.The remainder begins to flow downhill,commencing its lengthy journey from brook to stream to lake,or to a river that will carry it to the sea.
As water flows along the ground,it picks up sand,pebbles,even boulders.It uses them to gnaw at the sides and bottom of its channel,gradually loosening more earth.
By this process enormous amounts of mud and rock are moved from the land to the sea.Each year the Mississippi Rivercarries 730 million of solid matter into the Gulf of Mexico.
This constant hauling of land into the sea is lowering the United States' average height above sea level at a rate of about one foot every 9,000 years.If erosion continues at the same rate,the United States will be worn completely down to sea level in about 23 million years.
2007-9-2 16:48
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The Best Season for Thinking
If you are like most people,your intelligence varies from season to season.You are probably a lot sharper in the spring than you are at any other time of year.A noted scientist,Ellsworth Huntington(1876-1947),concluded from other men's work and his own among peoples in different climates that climate and temperature have a definite effect on our mental abilities.
He found that cool weatner is much more favorable for creative thinking than is summer heat.This does not mean that all people are less intelligent in the summer than they are during the rest of the year.It does mean,however,that the mental abilities of large numbers of people tend to be lowest in the summer.
Spring appears to be the best period of the year for thinking.One reason may be that in the spring man's mental abilities are affected by the same factors that bring about great changes in all nature.
Fall is the next-best season,then winter.As for summer,it seems to be a good time to take a long vacation from thinking!
2007-9-2 16:48
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A Dream Laboratory at the Unlversity of Chicago
A unique laboratory at the University of Chicago is busy only at night.It is a dream laboratory where researchers are at work studying dreamers.Their findings have revealed that everyone dreams from three to seven times a night,although in ordinary life a person may remember none or only one of his dreams.
While the subjects——usually students——sleep,special machines record their brain waves and eye movements as well as the body movements that signal the end of a dream.Surprisingly,all subjects sleep soundly.
Observers report that a person usually fidgets before a dream.Once the dream has started,his body relaxes and his eyes become more active,as if the curtain had gone up on a show .As soon as the machine indicates that the dream is over,a buzzer wakens the sleeper.He sits up,records his dream,and goes back to sleep——perhaps to dream some more.
Researchers have found that if the dreamer is wakened immediately after his dream,he can usually recall the entire dream.If he is allowed to sleep even five more minutes,his memory of the dream will have faded.
2007-9-2 16:49
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The Grand Banks,the Richest Fishing Ground in the World
John and Sebastian Cabot sailed back across the North Atlantic with bad news for their patron,King Henry Ⅶ of England.Instead of a short sea route to Japan and India,they had found only rocky,icy coasts.
It was as a mere afterthought that they mentioned that they had visited a place near what they called New Found Isle.The codfish were so plentiful there that when the sailors had lowered baskets into the water and hoisted them up,they were full of squirming,silvery fish.
Although the merchants and the nobles at court did not care about this discovery,the fishermen of Europe became very interested.Before long,many fishermen were sailing across the Atlantic to Newfoundland in their little fishing boats and bringing back great numbers of dried fish for the kitchens of Europe.
In time,the right to fish the Grand Banks came to be considerde far more valuable than all the treasure of the fabled East.The Grand Banks were,and still are,the richest fishing ground in the world.
2007-9-2 16:50
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The American Museum of Natural History
When an art museum wants a new exhibit,it buys things in finished form and hangs them on its walls.When a natural history museum wants an exhibit,it often must build it realisti-cally-from a mass of material and evidence brought together by careful research.
An animal,for example,must first be skinned.Photographs and measurements are used to determine the animal's structure in a natural position——fighting,resting,or feeding.Then muscle forms are built and a plaster shell is made.Finally the skin is pulled over the shell like a wet glove.This completes the animal subject.
Displaying such things as stone heads,giant trees,and meteorites is basically mechanical.Most other natural history exhibits present more difficult problems.For instance,how can a creature be exhibited when it is too small to be seen clearly?In these cases,larger——than——life models are built.The American Museum of Natural History has models of fleas,houseflies,and a myriad other insects enlarged up to seventy-four times.The models show the stages of the insects' development and the workings of their bodies.
2007-9-2 16:50
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The Tundra of the Arctic Regions
These are the signs of the coming arctic winter:The color of the tundra changes as the water grasses turn brilliant red.The migratory birds gather in flocks along the coast and gradually drift southward.Most of the birds that have spent the brief summer on the tundra now disappear,leaving only the golden eagle,the gyrfalcon,the ptarmigan,and the snowy owl to brave the sunless northern winter.
As the lakes and ponds freeze over,a thin mantle of snow covers the sedge.Occasionally a young and inquisitive arctic fox may be seen loping across the tundra.The weasel and the lemming begin to change color;as the winter deepens,their coats will turn snow-white.
During the first week in August the arctic sun dips below the horizon for the first time since May——it has not set all summer long.The gold and purple sunsets color the subfreezing waters of the Arctic Ocean.
By the end of September or early October the tundra is dark and seems deserted;winter has taken hold of the arctic for another nine long months.
2007-10-10 14:23
wangjin1982_0
thank you, It's very useful
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