“One thing I enjoy about my job is that I can work on something that is actually active,” says Game McGimsey, an American volcanologist (火山学家). Part of his job includes keeping an eye on Alaska's many active volcanoes and giving people a heads-up when a volcano might erupt (喷发).

    Like most jobs in the sciences, volcanology requires a lot of education. McGimsey received an undergraduate degree in geology at the University of North Carolina, then landed an internship (实习期) with a geologist at the USGS (美国地质勘探局) whose area of expertise was volcanoes. After earning a graduate degree at the University of Colorado, McGimsey accepted a job with the USGS and has been with the Alaska Volcano Observatory for 25 years.

    Volcanoes can influence the world in ways we might not think about. For example, on Dec. 15, 1989, a 747 jetliner (a large airplane) flew through a thick ash (灰) cloud produced by Mount Redoubt, an Alaskan volcano that hadn't erupted in 25 years. The ash caused all four engines to die, and the plane's electronics went dead.

    “The plane was within several thousand feet of flying into the mountains below when the pilots got a couple of the engines restarted and landed safely in Anchorage,” McGimsey says. It cost nearly $80 million to repair the damage to the plane.

    Such situations show just how dangerous volcanoes can be. However, volcanologists know the risks and are prepared to protect themselves.

    “There is certainly a higher danger level in volcanology than some other jobs,” McGimsey admits. “We understand how serious the danger is, and we don't like taking unnecessary chances. We avoid getting too close to an erupting volcano, because it's not worth injury or death simply to get a rock or a photograph.”

B

    My friends and I had just finished lunch at a hotel when it started to rain heavily. When it became lighter, I decided to get my car which was parked at my office three streets away.

    My friends argued that I shouldn't go, mainly because I was seven months pregnant（怀孕的）then. I made it clear to them that I'd be very careful. One of them wanted to come with me but I insisted that she stayed with another friend who needed help with her baby.

    I walked out of the hotel and started making my way to the car. At the crossing, a van stopped and a man came out with an umbrella. Before I knew what was happening, he walked right beside me and told me he'd escort（护送）me to my destination. Although I was very embarrassed and refused, he insisted that he would.

    During our walk, he kept telling me to walk slower, as the ground was wet. When we got to the car-park, I thanked him and he went away. I did not get his name and may not even recognize him now. Did he purposely stop for me? I'll never know.

    So how did I pay it back? I was at home when I noticed two Indian construction workers walking in the heavy rain. They were probably on their way to the working place near my home. I went out and passed them an umbrella. They were completely surprised by my action, and I told them they should take and keep it. They were very grateful to me, probably wondered why a stranger was offering such kindness. I was so relaxed and happy that day.

    James Cleveland Owens was the son of a farmer and the grandson of black slaves. His family moved to Cleveland when he was 9. There, a school teacher asked the youth his name.

    "J.C. "he replied.

    She thought he had said "Jesse", and he had a new name.

    Owens ran his first race at age 13. After high school, he went to Ohio State University. He had to work part time so as to pay for his education. As a second year student, in the Big Ten games in 1935, he set even more records than he would in the Olympic Games a year later.

    A week before the Big Ten meet, Owens accidentally fell down a flight of stairs. His back hurt so much that he could not exercise all week, and he had to be helped in and out of the car that drove him to the meet. He refused to listen to the suggestions that he give up and said he would try. He did try, and the results are in the record book.

    The stage was set for Owens' victory at the Olympic Games in Berlin the next year, and his success would come to be regarded as not only athletic but also political. Hitler did not congratulate any of the African American winners.

    "It was all right with me," he said years later. "I didn't go to Berlin to shake hands with him, anyway."

    Having returned from Berlin, he received no telephone calls from the president of his own country, either. In fact, he was not honored by the United States until 1976, four years before his death.

    Owens' Olympic victories made little difference to him. He earned his living by looking after a school playground, and accepted money to race against cars, trucks, motorcycles and dogs.

    "Sure, it bothered me," he said later. "But at least it was an honest living. I had to eat."

    In time, however, his gold medals changed his life. "They have kept me alive over the years, "he once said." Time has stood still for me. That golden moment dies hard."

    When we want to tell other people what we think, we can do it with the help of words. We can also do it in many other ways, too. Sometimes we move our heads up and down when we want to say "yes", and we shake our heads when we want to say "no". Some people can't hear or speak. They talk with the help of gestures（手势）. People from other countries often have to do it if they don't know your language.

    Here is a story. An American was once having his holiday in Italy, but he could not speak Italian. One day he went to a restaurant and sat down at a table. When the waiter came, the American opened his mouth, put his fingers in it and took them out again. In this way he wanted to say "Bring me something to eat". The waiter soon brought him a cup of tea. The American shook his head and the waiter understood that he didn't want tea. So he took it away and brought him a glass of milk. The American shook his head again. He was very hungry now and looked sad. He was just going to leave the restaurant when another man came in. When this man saw the waiter, he put his hands on his stomach(胃). In a few minutes there was a large plate of bread and meat on the table in front of him.

    Fashions have a lot of rules. Most of them, however, are just wrong. But there's one rule that goes beyond tradition and into the field of scientific study of the brain: Black clothes are slimming. It all comes down to how your visual system processes the light. The below holes in each square are the same in size, yet the white hole looks bigger than the black hole.

    In the 1500s, Galileo Galilei noticed that some of the planets looked larger when viewed with the naked eye than they did when viewed through a telescope, making the white light of Venus appear eight to ten times larger than Jupiter in the night sky. He knew something strange must be going on with his vision to cause this illusion, but he wasn't sure what it was. Luckily, scientists never stopped wondering, and in 2014, they figured it out.

    Our visual system operates via two main channels: "on" neurons (神经元) that are sensitive to light things and "off" neurons that are sensitive to dark things. When it came to the dark "off" neurons, the researchers found that they responded predictably to dark shapes on a light background the greater the contrast between the two, the more active these neurons were. But the light on" neurons behaved unpredictably. Even with the same amount of contrast, light objects on a dark background caused a greater response in these neurons.

    This phenomenon makes some sense, evolutionarily speaking. In the dark of night, you'd want to be able to take in every bit of light you can get, so a visual system that enlarges light objects on a dark background could be very useful. However, it's not that hard to see dark objects in the light of day. It has some effects in the colors of your clothes and in the appearance of the planets—the brighter appearance of Venus in the night sky makes it look bigger than the darker Jupiter.