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When was rubber discovered?

Although the remarkable properties of the rubber tree were known to the Aztecs and other South American Indians, for perhaps a thousands years, rubber was unknown in Europe until the discovery of the New World. Pietro Martyre d’Anghiera, chaplain to the court of Ferdinand of Aragon, Castile and Leon, gave the first written account of the elastic gum in his …

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When was history made in twelve seconds?

The date was 17 December 1903; the scene: the cold windy hills of North Carolina; the name of the place which was to go down in history: Kitty Hawk; the occasion: man’s first powered flight. The aeroplane had arrived. Orville Wright (one of the two aviation pioneer brothers, Orville and Wilbur) was at the controls. The aircraft, powered by a …

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When was concrete invented?

Concrete can be said to have been used for thousands of years, if the words is taken generally to mean a hard building material produced from a mixture of cement, sand, gravel and stone. The Assyrians and Babylonians used clay to bind sand and stones, and the ancient Egyptians discovered lime and gypsum. The Romans mixed slaked time with volcanic …

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When was a sea captain treated like a god?

On 17 January 1779 two ships of Captain James Cook anchored in Kealakekua Bay, Hawaii. The natives believed that in ancient times Lono, god of fertility and cultivated foods, came down from the sky. Lono was honoured in the Makahiki festivities that lasted from October to February. When Cook landed, the people greeted him as Lono. Priests brought offerings, and …

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When the first rocks were formed?

In the violent beginnings of our planet the surface of the Earth looked a terrifying place. White-hot magma, formed of molten rock from the Earth’s interior, boiled on the surface with constant explosions. At the same time showers of meteorites and cosmic dust, attracted by the pull of the Earth’s gravity, made the sphere grow bigger and bigger as it …

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When the first mountains were formed?

As it gradually cooled, the magma solidified on the surface and the Earth became covered with a crust of primeval rocks, mainly consisting of granite and basalt. These rocks encased our globe like a rigid shell, while inside it continued to be burning hot. When the Earth cooled still more it shrank, and the rocky layer which covered it had …

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When is the best time to launch a rocket to the moon?

There is virtually no “best time” to launch a rocket to the moon, because, in terms of space travel, the journey is so short. The average distance is 238,000 miles, with a maximum variation of only 25,000 miles. A space shot, whether to the moon or some other object, is made by a rocket already in orbit. To take a …

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When is a country not a country?

Occasionally, civil wars occur which lead to a country being divided in two. For example, a war in Pakistan in 1971 led to the creation of the new nation of Bangladesh. Not all new countries, however, win international recognition. For instance, Cyprus has been divided, through the breakaway Turkish Republic of Northern Cyprus, established in 1983, is recognized only by …

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When does litmus paper turn red?

Litmus paper turns red when placed in an acid solution, but blue if the solution is alkaline. This absorbent paper is the oldest and most commonly used indicator of the presence of absence of acid. Its special qualities are due to the fact that it has been soaked and impregnated with a mixture of dyes called litmus. The litmus mixture …

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