Birches have long been known for their beautiful bark. People use birch wood to make furniture, flooring, and plywood.
Birch trees are found in the northern half of the world. They grow in areas with cool to cold weather.
There are about 170 species of birch worldwide. They have narrow trunks and their bark is often white with black lines. Its leaves are usually bright green and they turn golden yellow in the fall. Birch flowers are called catkins. Each catkin bears flowers of only one sex but male and female catkins occur on the same plant. The fruit is a one-seeded nut which is often winged.
In Russia, birch switches are traditionally used to beat one’s skin during sauna baths.
The sap of birches is sweet and can be collected and condensed into syrup.
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The goldfish is a popular fish to keep as a pet in aquariums and ponds. It also lives in the wild, in rivers and lakes. The goldfish is a member of the carp family. Carassius auratus is its scientific name.
There are more than 125 breeds of goldfish found throughout the world. They can be of different colors: gold, red, orange, white, black, but naturally they are greenish brown or gray. That is because 1,000 years ago people in China began breeding goldfish to create more colorful varieties.
Wild goldfish eat mostly plants and small animals.
A female goldfish can produce thousands of eggs during each breeding season.
Some fish live as long as 25 years.
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Rain is the liquid form of water that falls from the sky in drops. Rain fills lakes, ponds, rivers, and streams. It provides the freshwater needed by humans, animals, and plants. Rain is a part of Earth’s endless water cycle.
It may sound a paradox, but it is actually rain that keeps the earth dry. If the moisture was not taken out of the air and formed into clouds, it would condense on every solid surface. We would feel as if we were in a steam bath.
Rain falls almost everywhere on Earth. One of the world’s rainiest places is Mount Waialeale in Hawaii. It rains about 350 days a year there. One of the driest places on Earth is the Atacama Desert in Chile.
The Sahara desert in Africa is very dry. Rain never falls on some parts of it. It is true that clouds pass over those areas and actually drop rain but the rain never touches the ground. The heat of the desert air evaporates the moisture as it falls.
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Clouds are made of water—thousands of gallons of water, floating high in the air. It’s easier to believe this when you know that cloud water takes the form of tiny droplets. The droplets are so tiny that you couldn’t see one if it was separated from all the others. If all these water droplets in a cloud meet a mass of warm air they evaporate – and the cloud disappears! This is why clouds are constantly changing shape.
Sometimes the water droplets join together around tiny pieces of dust in the air. These drops get bigger and bigger as more droplets collect. When they become too heavy to float, they fall.
There are three main kinds of clouds. “Cumulus” refers to the small puffballs or great wooly-looking clouds that are flat on the bottom. “Stratus” are low clouds, usually streaky or without much shape. And “cirrus” are light feathery clouds, like the ones in the photo. Sometimes cirrus clouds are so high, where the air is very cold, that the whole cloud is made of ice.
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When you are on the beach, you are stepping on ancient mountains, skeletons of marine animals, even tiny diamonds.
As children we play on it and as adults we relax on it. We complain when it gets in our food and we praise when it’s moulded into castles.
If we looked at it, we would discover an account of a geological past and a history of marine life that goes back thousands and in some cases millions of years.
The sand covers not just seashores, but also ocean beds, deserts and mountains. It is one of the most common substances on earth. And it is a major element that people use.
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Some people believe that graffiti is an example of anti-social behavior, the work of vandals. It was earlier when teenagers wrote swear words and gang names on the fences and pavement. Nowadays, many of those ‘vandals’ are treated as respected artists, and some of them have made it in the world of business.
Now graffiti has the status of ‘street art’. You can see it in advertisements, on clothes, on toys.
The term graffiti comes from the Greek word ‘graphein’ which means ‘to write’. Graffiti was discovered in countries of the Ancient East, Greece, Rome (Pompeii, the Roman catacombs). The earliest graffiti appeared in the 3rd millennium BCE. Then they were presented in the form of prehistoric cave paintings and pictographs. The drawings were often made in the ritual and sacred places in caves. Most often, they portrayed animals, wildlife and hunting scenes.
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Guggenheim Museum is home to one of the world’s top collections of modern art. This strangely- shaped house is one of the most famous buildings in New York.
Solomon R. Guggenheim, a rich American businessman, was fond of art. When he retired from business he began collecting art seriously. His friend Hilla Rebay, a German baroness and artist, helped him to buy pictures for his collection.
Solomon’s favorite artist was Russian painter Wassily Kandinsky, who became the first ‘abstract’ artist in the world. Kandinsky believed colors and forms could express and inspire. Guggenheim was so fascinated by Kandinsky’s works that he bought more than 150 pictures by the Russian artist. He also collected pictures by other Modernist artists – Marc Chagall, Pablo Picasso, Amedeo Modigliani, Paul Klee.
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