Rocks that were formed in the last 2,800 million years can be found in every continent, but rocks more than 3,500 million years old are extremely rare. Some rocks in the American Minnesota River valley and others in western Greenland have been dated at about 3,800 million years. The world’s oldest rocks, however, are probably in Australia, where, in 1983, …

Venus in the hottest of the Sun’s planets. Space probes have measured the temperature on its surface as a scorching 4600 C (9500 F). The reason is that Venus is surrounded by a dense atmosphere of carbon dioxide, which traps the Sun’s heat like a greenhouse. The coldest planet is distant Pluto, whose surface has a temperature of -2300 C …

About 2.15 per cent of the world’s water supply is frozen. Most of the ice is blocked in two great ice sheets, the largest blanketing most of Antarctica and the other in Greenland. Smaller ice caps occur on northern islands, including Iceland, Spitzbergen and various islands in northern Canada. Valley glaciers are smaller still. They are found on mountain slopes …

Our galaxy, vast island of stars though it is, is only one of millions of similar galaxies scattered throughout space as far away as we can see through cur telescopes. The nearer galaxies to our galaxy are two small satellite galaxies called the Magellanic Clouds. They can be seen only in the southern hemisphere, and look like pieces torn out …

The parachute was invented by Andre-Jaques Garnerin of France who made the first descent over the Parc Monceau, Paris, on October 22, 1797 when he was released from a balloon at a height of 2,230 ft. He rode in a gondola. The parachute had a diameter of 23ft, was supported by a rigid pole, and had its 32 white canvas …

Since the very early days of their history men have been making bricks of clay or other materials for use in building. The Tower of Babel, for which, according to the Old Testament, ‘they had brick for stone’, was probably a brick temple. People who lived in ancient Egypt built their houses from both sun-dried and kiln-baked bricks.

Cereals, of course, in the general sense, including wheat, rice, maize (known as corn in Canada and the United States), rye, oats and barley were among the earliest plants grown by man. But packaged or processed cereals are a modern development. Breakfast cereals owe their origin to the vegetarians of the last century and health fanatics who believed they could …

The first known lighthouse was the Pharos of Alexandria in Egypt, a 400 tower built about 280 B.C. A wood fire was kept burning on the top of the tower, which became one of the Seven Wonders of the World. Before this the light from volcanoes had acted as a guide for sailors. The first lighthouse in Britain was built …

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 …

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 …