The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid—we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

    However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴)native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we，d need huge feet that we could bring up to our ears in order to create adequate w hitting. ''

    But fortunately there is an alternative : cornflour. By adding enough of this common thickening agent to water (and it does take a lot), you can create a “non-Newtonian” liquid that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子）in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick Liquid of cornflour.

    Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink--and take a shower afterward!

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    The wonderful experiment I am going to introduce proves that air is just all around and that it presses down upon us. Air pressure is a wonderful force. When you swim underwater, you can feel water push down your body. The air all around you does the same. However, your body is so used to it that you do not notice this. The pressure is caused by a layer of air called the atmosphere. This layer surrounds the Earth, extending to about five kilometers above the Earth's surface.

    The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now for the experiment！

    What you need:

·A hard-boiled egg without the shell

·A bottle with a neck slightly smaller than the egg

·A piece of paper

·A match

Method:

1） Check that the paper will sit firmly on the neck of the bottle.

2） Tear the paper into strips and put the strips into the bottle.

3） Light the paper by dropping a burning match into the bottle.

4）Quickly sit the egg on the neck of the bottle.

Result:

    Astonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.

    Why it happened

    As the paper burns, it needs oxygen and uses up the oxygen（air）in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! This proves that air is all around and that it is pressing down on it.

    In 1971, UN scholar Paolo Lugari started an eco-social experiment in Gaviotas, Colombia. Located in one of the most extreme climates, Gaviotas was described as a sustainable, self-sufficient village in an area that Lugari called 'just a big, wet desert'.

    'They always put social experiments in the easiest places,' Lugari said.'We wanted the hardest place. We figured if we could do it here, we could do it anywhere.'

    'Lugari just thought that someday the world would become so crowded that humans would have to learn to live in the planet's least desirable areas,' wrote Alan Weisman, author of Gaviotas: A Village to Reinvent the World.

    Today, Gaviotas is an eco-village with about 200 people. They farm organically. They use wind and solar power. Since 2004, Gaviotas has been 100% fossil fuel independent. The residents also enjoy free housing, schooling, and community meals. Shockingly, there are no weapons, no police, no jail and no mayor. But though these elements would make any social experiment a success, perhaps the most remarkable accomplishment is the planting of 1.5 million pine trees and palm trees. The various results of this new tree growth have been incredible. The shade of the trees has inspired the return of many rainforest species that were once native to the region. Additionally, the residents of Gaviotas enjoy a sustainable source of income from the resin(松香) harvested from the trees.

    The United Nations named Gaviotas a model of sustainable development. The Colombia novelist and Noble Prize winner Grabriel Marquez called Lugari the 'inventor of the world'.

    A new study by a team of researchers has found that 'nature's capacity to store carbon is steadily falling as the world's farmers expand croplands at the cost of the native ecosystem such as forests'.

    Considering this disturbing fact—and as the world population increases towards an estimated 9 billion by the year 2050 and global warming continues to increase the planet's surface temperature—Gaviotas stands as one shining example of how things could be different.

    Two men, Alan and Henry, both seriously ill, shared a hospital room. Alan was allowed to sit up in his bed and his bed was next to the room's only window. Henry had to spend all his time flat on his back.

    The men talked for hours, of their wives, families, their homes and their jobs. And every afternoon when Alan, in the bed next to the window, could sit up, he would pass the time by describing to his roommate all the things he could see. Ducks and swans played on the water while children sailed their model boats. Lovers walked arm in arm among flowers. Trees and skyline could be seen in the distance. As he described all this, Henry, on the other side of the room, would close his eyes and imagine the scene.

    One warm afternoon Alan described a parade (游行) passing by. Although Henry could not hear the band, he could see it in his mind. Unexpectedly, an alien thought entered his head: why should he have all the pleasure of seeing everything while I never got to see anything? It doesn't seem fair. Henry felt ashamed at first. But as the days passed and he missed seeing more sights, his envy grew and soon let him down. He began to find himself unable to sleep. He should be by that window — and that thought now controlled his life.

    Late one night, as he lay staring at the ceiling, Alan began to cough. He was choking. Henry watched in the dim room as the struggling man tried hard to reach for the button to call for help. Listening from across the room, he never moved, never pushed his own button which would have brought the nurse running. In less than five minutes, the coughing and choking stopped, along with the sound of breathing. Now, there was only silence — deathly silence.

    As soon as it seemed appropriate, Henry asked if he could be moved next to the window. The nurse was happy to make the switch and after making sure he was comfortable, she left him alone. Slowly, painfully, he struggled to take his first look. Finally, he would have the joy of seeing it all himself. He looked out, but faced a blank wall.

    When it's five o'clock, people leave their office. The length of the workday, for many workers, is defined by time. They leave when the clocks tell them they're done.

    These days, the time is everywhere: not just on clocks or watches, but on cellphones and computers. That may be a bad thing, particularly at work. New research shows that clock based work schedules hinder creativity.

    Clock-timers organize their day by blocks of minutes and hours. For example: a meeting from 9 a. m. to 10 a. m, research from 10 a. m to noon, etc. On the other hand, task-timers have a list of things they want to accomplish. They work down the list, each task starts when the previous task is completed. It is said that all of us employ a mix of both these types of planning.

    What, then, are the effects of thinking about time in these different ways? Does one make us more productive? Better at the tasks at hand? Happier? In experiments conducted by Tamar Avnet and Anne-Laure Sellier, they had participants organize different activities from project planning, holiday shopping, to yoga by time or to-do list to measure how they performed under "clock time" vs. " task time". They found clock timers to be more efficient(有效率的) but less happy because they felt little control over their lives. Task timers are happier and more creative, but less productive. They tend to enjoy the moment when something good is happening, and seize opportunities that come up.

    The researchers argue that task-based organizing tends to be undervalued and under-supported in the business culture. This might be a small change to the way we view work and the office, but the researchers argue that it challenges a widespread characteristic of the economy: work organized by clock time. While most people will still probably need, and be, to some extent, clock-timers, task-based timing should be used when performing a job that requires more creativity. It'll make those tasks easier, and the task-doers will be happier.

    In most people's opinion, the tiger is not an animal that we would ordinarily think of as being chicken. However, one tiger, which lives in an English zoo, turned out to be more cowardly (胆小的) than his keepers could ever have imagined.

    Tanvir, a two-year-old Bengal tiger, got stuck at the top of a new 5m-high activity tower in the zoo, after climbing it for the first time.

    The wooden tower had been designed to provide mental exercise for Tanvir by testing his ability of dealing with troublesome situations, but after climbing it in just a few seconds, he lost his courage when it came to coming back down. Tanvir went on to spend nearly two days at the top of the tower trying to collect the courage to attempt to get down.

    A spokesperson for the zoo said that several days before Tanvir had taken half an hour to get down a lower tower only 1.5m high, and the taller tower had clearly been too much challenging for him.

    "Every time he got to the edge, he looked out, put a paw over, and thought, 'no, I cannot make it!" 'laughed Samantha Cordrey, Tanvir's keeper. In the end Tanvir's hunger defeated his fear, and after almost 48 hours he made his way down. Burying himself in a big meal just like a hungry pig, Tanvir seemed to forget such a shameful experience for a while.

    It appears that his experience would not be the worst in Tanvir's life if he continued to act like a chicken. It is not known whether he will take courage to go back up his exercise tower again.

    The whole episode (插曲) only serves to show the difficulties faced by zoo staff in creating environments that will improve animals' living ability in enclosed space.