People dreamed of the construction of the bridge across the Golden Gate Strait, which would connect San Francisco and Marin County, back in the XIX century. But only at the beginning of the XX century there were real technical possibilities for its construction. Engineer Joseph Strauss, developer of about 400 bridge structures, proposed to extend the suspension bridge with two supports over 2.5 km in length. People didn’t believe that it was possible to build such a bridge, but they became interested in the project.
Motorization in many ways accelerated the process of creating a bridge across the Golden Gate Strait. San Francisco grew rapidly, and the number of cars on the streets of the city increased.
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It is the largest hydroelectric power plant on the Eurasian continent. Its construction on the Siberian Yenisei River began in 1968. Today the dam height reaches 245 m and it is over 1 km long. The first ten 640 MW hydropower units were launched in 1978. Currently, all ten hydropower units in total produces 6400 MW, it is considered the world’s third power.
The Yenisei River is the deepest and most powerful river in Russia. The average water consumption is 19.8 thousand cubic meters per second.
They were going to build many power plants in the Soviet Union in 60s of the XX century. Electricity would be enough for Far East, but the construction was dictated not only by the desire to get cheap electricity. Deposits of marble, non-ferrous metals were discovered near the Yenisei and they began construction of the aluminum plant.
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A windmill is a machine that harnesses the power of the wind. It may be used to grind grain into flour, to pump water, or to produce electricity.
The blades are mounted on a tall tower and spin around when wind blows on them. Blades are connected to a vertical shaft, which powers, for example, a water pump or millstones.
People in western Asia built the earliest known windmills more than 1,000 years ago. They spread to Europe by the 1100s. By the 1800s, however, many people used steam engines rather than wind power.
Today wind turbines produce electricity for many communities.
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The name LEGO was made up of two Danish words – Leg and Godt, which together mean “play well.” A few years later the founder of the company found out that LEGO in Latin means “I study”.
Few people know that the most well-known toy company was started as a wood products factory.
LEGO history dates back to 1932. Ole Kirk Christiansen founded the Danish company to produce goods for daily use. All products were made of wood. At first ordinary ladders and ironing boards brought profit. But soon the global financial crisis came, and demand for these products had fallen significantly. Therefore, after analyzing the market, he concluded that even in the most difficult times the toys were bought. The factory began producing toys, and of course, the first toys were made of wood.
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In 1900, American engineer John Elfreth Watkins wrote an article in Ladies’ Home Journal on what would happen in 100 years. Now it turned out that the author had made some interesting predictions. In particular, he was able to describe mobile phones, TV, digital photo, aircraft, tanks and even more. Nevertheless, in his article, which was entitled “What can happen in the next century,” Watkins made several predictions that had not come true.
John Watkins worked for the magazine Saturday Evening Post, which was published by the same publisher as the Ladies’ Home Journal. The editor of the historical department of Saturday Evening Post Jeff Nilsson saw an old article and decided to publish it after 112 years.
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Balloons are lighter-than-air craft that are filled with a gas or heated air. Experiments with balloon flight led to the development of the motor-powered airship and later the airplane.
Balloons can be used for advertising, scientific experiments and entertainment.
Balloons filled with the heated air are called Montgolfière-style hot air balloon. Balloons filled with hydrogen or helium are called Charles Hydrogen Balloon (however, hydrogen is now almost never used because of its explosiveness). Rozière balloon is a hybrid balloon filled with both gas and hot air.
Bags of sand are hung around the basket for ballast, or extra weight, so that the balloon does not rise too fast.
In 1783, brothers Joseph-Michel and Jacques-Etienne Montgolfier made the first successful experiments with hot-air balloon flights. A sheep, a rooster, and a duck were the first balloon passengers. The first balloon weighed 140 kg and rose to a height of more than 1.5 km.
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Panama Canal is the only navigable canal, which connects the Atlantic and Pacific Oceans. It was dug through the Isthmus of Panama for ten years, from 1904 to 1914. Since that time, the sea route from New York to San Francisco shortened more than doubled, from 22 500 km to 9000 km. The total length of the channel is 81.6 km. Since 2000, the channel is owned by the government of Panama.
Oceangoing vessels that are headed from the Atlantic Ocean to the Pacific came to gateways, where they gradually raised to a height of 26 m. Then, on the waters of an artificial Lake Gatun ships sail to other gateways and come to the Pacific Ocean. After about nine hours of travelling they are in the Bay of Panama.
From 30 to 45 vessels of different types and sizes pass through the channel every day. Payment depends on the tonnage. 40 thousand tons are the maximum allowed. In total about 14 thousand ships are ferried every year.
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