Major floods can occur in several different ways. For example, in 1840, an earthquake caused a landslide in the Himalayas, damming the upper course of the River Indus, so that a lake soon formed. The lake was 64 km (40 miles) long and over 300 m (984 ft) deep, and when this natural dam broke, flood water swept down the …

It you walk down a street in any town or city, you will see lots of people with different coloured skin: white, black, yellow and coffee colours all appear. But why do people have different coloured skin? The reason is that in your skin you have substances which, under certain conditions and with the correct chemical processes, make colour – …

To understand this, we should first realize that our skin is in two layers. There is the outer layer and the inner one which carries nerves and blood-vessels. Beneath the skin is a loose layer of tissue which contains fibres that run in all directions. A few of these fibres are attached to the under-surface of the skin so that, …

A Wave snakes are long red tubes that help convert the motion of waves into electricity and form part of a commercial wave power station. It was developed by a British company and took 10 years to create. Currently, the pilot wave-power project has been launched off the coast of a Portuguese town called Agucadoura, and aims to power 1,000 …

Wormhole (not warm hole) is a hypothetical feature of the universe and is basically a shortcut through space and time. The name wormhole is derived from the analogy that a worm on the circumference of an apple can either go all around it or dig its way through to get to the other side. As is obvious, by digging through, …

In order to raise chicks the farmer keeps the eggs warm and is careful not to crush them. But when scientists in the University of Southern California rear tubeworms, they keep the immature worms very cold and under high pressure. You would think the scientists are being cruel by subjecting these little worms to such extreme conditions. They are not. …

Ungulates are hoofed mammals that walk on their toes. The word ungulate comes from the Latin word “unguis”, which means nail, claw or hoof. Ungulates are divided into two classes: even-toed ungulates such as deer, giraffe, antelopes, and odd-toed ungulates such as horses, zebras and rhinoceroses.

T-rays stand for terahertz radiation. It is used to scan airline passengers for explosives and illegal drugs. The rays are particularly effective, as they can see through clothing, paper, leather, plastic, wood, and ceramics. They don’t penetrate as well as x-rays, but they also don’t damage living tissue. They can read spectroscopic signatures, detecting the difference between, say, hair gel …

Transparent soaps are made of glycerin, and are partly soap and partly solvent. Sodium hydroxide causes crystals to form in soap, which is why the soap becomes opaque. In order to make it transparent, the soap has to be dissolved in enough solvent to make the crystals so small that light passes freely through, making the soap look transparent. There …

Some people become very frightened during a thunder storm, but there’s really nothing to worry about. Lightning is the result of a collision between two electrical charges one positive, and the other negative either in two clouds or in a cloud and the earth. When the difference between the two charges becomes great enough, a great spark the lightning jumps …