CRYSTALS

WHY DO CRYSTALS FORM IN SUCH BEAUTIFUL SHAPES?

Pure crystals always form in regular shapes of particular kinds. Salt forms tiny cubes, and many crystalline minerals consist of beautiful formations of smaller identical crystals.

Crystals take these shapes because the tiny atom inside them are lined up in particular patterns of rows. When the crystal forms, its atoms link together at certain angles. The crystal enlarges as more and more atoms link to those in the crystal at the same angles. In this way the whole crystal grows in a specific shape.

HICCUPS

WHAT HAPPENS WHEN YOU HICCUP?

Hiccups or hiccoughs are caused by sudden movements of your diaphragm, which is a large muscle beneath your chest. The diaphragm controls breathing, and the movement causes a sudden intake of air. This is a hiccup.

Hiccups can start for many reasons, but they usually soon go away. Sometimes the attack can last for a long time and it can be exhausting. In very rare cases it can last for years.

DIABETES

WHY ARE SOME PEOPLE DIABETIC?

Diabetics are people who suffer from diabetes. The main kind of diabetes affects the pancreas, which is a gland that produces a hormone called insulin. This hormone controls the amount of sugar in the blood, which provides energy for the body. In diabetes, insufficient insulin is produced and the sugar levels are uncontrolled, resulting in illness.

Diabetes usually cannot be cured. But by taking insulin and following strict rules for diet and exercise, the effects can be prevented. In the future, doctors hope that a method of automatic sugar control will be developed so that diabetics need no longer be concerned with their condition. This method could involve bio-sensors to monitor blood sugar levels and release insulin when it is needed.

FIRST SUBMARINE

DID YOU KNOW THE FIRST SUBMARINE WAS POWERED BY JUST ONE MAN?

The first submarine to go into action was an american vessel called the Turtle (pictured above). It tried to attack a British warship in 1776, during the American war of independence. The Turtle was an egg shaped craft powered by one man, who sat inside and turned two handles connected to screw propellers outside. 

Manned by Sergeant Ezra Lee, the Turtles mission was to attach a mine to the warship's hull. The submarine worked well, but the bottom of the ship was lined with metal, preventing Sergeant Lee from attaching the mine.

IMPORTANT DISCOVERY

WHO MADE AN IMPORTANT DISCOVERY BY FEELING HIS PULSE?

The great Italian scientist, Galileo, made a famous discovery in 1581, while he was still a teenager. While attending services in Pisa Cathedral, a chandelier swinging in the air caught his eye. It seemed that the chandelier always took the same time to swing first one way and then the other, regardless of how far it swung each time.

As there were no accurate clocks in those days, Galileo measured the time of each swing by feeling his pulse and counting the beats. The answer was always the same. 

What Galileo had discovered was the pendulum. Using this, it proved possible at long last to build clocks which kept time accurately.

MIRAGE

WHAT IS A MIRAGE?

A mirage is a kind of optical illusion that occurs in hot, still weather. A pool of water suddenly appears in the distance. But on approaching, it seems to evaporate and there's actually no water at all. 

You may see these mirages on roads in the summertime. They also occur in deserts, sometimes complete with trees, and may trick a thirsty traveller into thinking that an oasis lies ahead. 

What you really see is simply a reflection, usually of the sky. The reason is that a layer of hot air near the ground acts like a mirror.

Have you ever experienced a mirage? tell me in the comments below.

CENTURY TOO SOON

WHO FIRST THOUGHT OF COMPUTERS?

The idea of the computer first occurred to British inventor Charles Babbage (pictured above) in about 1833. Others had made calculating machines before him, but Babbage was the first person to conceive of a machine that could be programmed to carry out different calculating operations, as a computer can.

Babbage designed a machine called the Analytical Engine (pictured above) that had the basic features of a modern computer. It was to be a mechanical computer, containing complex systems of shafts and gear wheels. However, only parts of the Analytical Engine were ever built. The engineering required to complete it was far beyond the techniques of the age, and Babbage died in 1871 without knowing whether his computer would work or not.

In fact, Babbage was far ahead of his time as the first computer, a British wartime decoder called Colossus (pictured above), was not built until 1943 and it used electronics, as mechanical operations were too slow. Colossus and all other computers since are really the descendants of Babbage's Analytical Engine.