Child Labor Laws-Today on Congressional Moment：Over a hundred years ago the Industrial Revolution quickened the pace of manufacturing, and businessmen sought cheaper labor. Millions of children worked at dangerous jobs, and the national debate over...
Popcorn, like all grains, contains water. About thirteen and a half to fourteen percent of each kernel is made up of water. So when a popcorn kernel is heated above the boiling point of 212 degrees Fahrenheit, this water turns to steam. This steam cr...
Don: You know, Yael, no matter how much we talk about the need to stop global warming, sometimes it seems impossible. I mean, what are we actually doing about it? 唐：知道吗，雅艾尔，无论我们口头上多么需要遏制全球气候变暖，...
Don: Hi Yael, what's up? 唐：嗨，雅艾尔，有什么事吗？ Yael: Well Don, I just got off the phone with my friend. She's had a run of bad luck with relationships. She says that from now on she's only going to date musicians! 雅艾尔：唐，...
Some methods of preserving food are easy to understand. For example, it's easy to see that freezing your food, or packing it in salt, would make it inhospitable to the microbes which would otherwise cause it to spoil. You might wonder, however, about...
If you've ever driven on a highway during a heavy rain, you know about the danger of skidding. This waterskiing on the road is technically called hydroplaning, and it happens when water comes between the road and your tires, causing you to lose tract...
It's pretty easy to guess what most of your food is made of. The meat in your hamburger probably came from a cow, the bun was made from grain, the ketchup from tomatoes, and so on. There is one kind of food, however, that might have you guessing anim...
In the record of his life at Walden Pond, Henry David Thoreau reported on an odd phenomenon. As I walked on the railroad causeway, he wrote, I used to wonder at the halo of light around my shadow. Thoreau was probably seeing a phenomenon called heili...
Lots of people these days get their exercise at gyms and health clubs, oftentimes by walking or running on treadmillsthat is to say, running without going anywhere. If you've ever been on a treadmill for some time and then suddenly stepped off it, yo...
Piranha! For most people, the name sparks horror-movie images of vicious schools of fish that can reduce a human to a skeleton in minutes. 食人鱼！对大多数人来讲，这个名字会使人联想起邪恶鱼群的恐怖电影，这种鱼能使人...
During the space shuttle's third flight, back in nineteen eighty two, astronauts Jack Lousma and C. Gordon Fullerton saw something remarkable. Above the tail of the shuttle, where there should have been empty space, they saw a faint orange glow inste...
Playing a Frank Sinatra classic on a conch shell helped a local bicycle tour operator take top honors in an unusual musical competition.Lloyd Mager impressed judges at the 47th annual Conch Shell Blowing Contest with portions of Strangers in the Nigh...
If you love your job, part of the reason may be that you freely chose the work that you do. You were not forced to do it. But imagine a situation during wartime in which there were some soldiers or guards with guns standing above you, forcing you to...
Mammals developed from land-based reptiles two hundred million years ago, and most of the mammals we see today are still land based. A notable exception are the cetaceans, which we all know as dolphins and whales. How did they move from land to sea? 两...
You're on the deck catching rays, and even though you know you aren't supposed to tan without sunblock, you figure you'll be able to tell if you start to get really burned. Sure enough, after a little while you can see a redness coloring your skin, b...
