When were streets first named? Nobody can pinpoint exactly when streets were first named, but, presumably, people started to give streets names from the very earliest cities. Among the world’s first cities were Jericho and Çatalhöyük. They were both formed in about 7500 BC and began as a collection of a few hundred people, before […]
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Why don’t we notice when we blink? We don’t notice when we blink because our brain suppresses its visual center and makes sure our eyes are pointing in the same direction. Everybody is different, and we all blink a different number of times depending on the time of day, the condition of our eyes, the
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How does muscle memory work? Muscle memory works because the brain makes more efficient connections between neurons. We call it muscle memory because it feels like our muscles are working on their own, but the memory is down to the brain and the nervous system. The more you repeat an action, such as learning to
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How could you build a base on the moon? There are several problems involved with building a moonbase, but the biggest one is how to get all of the materials up there. NASA has just announced that they are going to spend $20 billion to put a base on the moon within the next seven
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When did people stop using canals? Canals began to die out in the early 1900s as they were replaced by faster railways and more powerful trucks. The building of canals in many countries peaked in the mid 19th century. Britain had a denser network of canals than any other country, and at the peak, there
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How do we make blood? Blood is made in our red bone marrow in a process called hematopoiesis. People have different quantities of blood depending on their size, but it is usually about 8% of a person’s body weight. 55% of the blood is made up of plasma, and the other 45% is a combination
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How does a jet engine work? A jet engine works by mixing fuel with compressed air and then burning it. The gas expands, shooting out of the back of the engine, which pushes the plane forwards. At first glance, it would be difficult to understand how a jet engine moves a plane along. We naturally
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Why did people start using wallpaper? People first started using wallpaper to insulate their houses, but only the rich could afford it. Later on, wallpaper became cheaper and people used it because they couldn’t afford tapestries to cover their walls. Wallpaper, along with paper itself, was invented in China. The earliest known wallpaper was used
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Do we still need weather balloons? Yes, weather balloons are still needed. Satellites can provide a lot of data, but they still cannot sample the atmosphere directly from inside it, and they are far more expensive. There are thousands of satellites in orbit around Earth at the moment, so it is easy to assume there
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Why do cats’ eyes glow in the dark? A cat’s eyes glow in the dark because they have a special reflective layer in their eyes called a tapetum lucidum. Cats aren’t the only animals whose eyes glow at night. The reason for this comes down to the way that we see and why we can’t
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