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Umbrella has always been one of the most useful ways of protection from the sun and the rain for those who have to work and walk outdoor in bad weather. The word umbrella comes from the Latin word ‘umbra’ meaning shade. But no one knows when or by whom the first umbrella was used. When the modern version of umbrella was invented, umbrellas were carried only by women, for they were not considered ‘manly’ enough to be used by men!

In very early times, in fact for thousands of years, umbrellas were used only for protection from the sun, rather than from the rain. It wasn’t until about 300 years ago that people began to use Waterproof umbrellas
in the rain.

Until around the year 1900 watches were carried in the pockets of vests or pants, and were tied
to the end. of a chain. Both the chain and the pocket were called the watch ‘fob’.

According to a popular story, a swiss watch maker saw a woman sittingin a park with a watch tied around her wrist, so that she could hold her child with both her hands free. He made a wristwatch in 1790, but no one really took notice of the great discovery and until about a century later the idea remained unused.

In 1914 a wristwatch was shown at an exhibition in Switzerland and people thought that it was “just a passing fancy”. Today, the same passing fancy” is the number one jewellery item in the world. Even an ordinary person can afford a wristwatch. About 80 million watches are made around the world each year!

Peice of metal shaped as fished used as a Compass in early China

South pointing spoon compas used by early Chinese for Feng Shui

It must have been very difficult for sailors and voyagers to travel through the vast seas without the help of modern gadgets to guide the way. In ancient times, sailors charted their course by the position of stars in the sky. In those days there was no such thing known as the compass. No one knows when or where the first compass was invented.

The earliest report of the use of compass appears in a Chinese book and the date given is the end of the 11th century A.D. The European ships used the compass in 1345. The early compasses consisted of an iron needle attached to a piece of wood or cork that floated in a bowl of water.

A really dependable compass was invented much later in the 19th century. But the compass is no longer used on ships - it has been replaced by a more efficient device called ‘gyrocompass’. This device reads the rotation of t_he earth and points to the true North Pole instead of the Magnetic North Pole

Modern magnetic Compass

                  

In the year 1795 a prize was announced by the French government for investing a way to preserve food for the  use of their army. A man named Francois Appert won the prize by devising a way to keep food fresh in sealed glass bottles by placing them in boiling water. But no one could explain why the food stayed fresh when treated that way, although it did not stray fresh for very long.

Again in 1829, William Underwood began selling bottled food in Boston. Ten years later, he used a tin-coated steel can instead of the glass bottle. The cans were assembled by workers and filled with food through a hole at the top. The hole was then sealed by a drop of solder.

In 1860, another American found a better process, to store food for longer periods. He heated the food inside cans at higher temperatures. Canned food has, since then, become one of the most popular way of preserving many food items.

Uranium is sometimes called the fuel source of the modern age. It has helped unlock the tremendous energy
hidden inside the atom. This atomic energy can be used for destructive purposes, but can also be used for generating energy for creative purposes. One kilogram of uranium can produce as much energy as nearly three
million kilograms of coal!

Pure uranium looks like silver or aluminium. But it is much heavier than other metals. A 0.3 cubic meter of uranium weights more than half a tonne.

Uranium is radioactive - this means its atoms break down slowly, releasing energy in the form of radiation. Some of its atoms are fissionable - which means they can be made to explode and break into two and in the process release vast amounts of energy. Because of these properties uranium is a very important metal. But extracting it from its ores to get it in its pure form is a complicated and expensive process.