It was not before sixteenth century, an Italian doctor named Jerome Cardan got the idea of teaching deaf-mutes through written characters. As a result of his work finger alphabets were developed, similar to the finger alphabets used today. With the help of finger alphabets, a deaf-mute makes the letters with his fingers and spells out words. He also depends on …

The lab technician selects a lens blank that has the correct segment (called an add) and a base curve close to the prescribed power. Then to make the power match the prescription exactly, another curve is ground on the back of the lens blank. In most labs, the equipment is designed to grind minus curves, so a strong, plus lens …

Clouds are formed when warm moist air rises into the sky. When it reaches a certain height, the warm air cools down and the water vapour in it condenses into small drops of water, forming clouds. There are several different types of clouds. The ones which are highest are usually made up of ice, and are the thinnest. These are …

Although the 1950s are most often considered the 3-D movie decade, the first feature length 3-D film, “The Power of Love,” was made in 1922. Since that time the use of 3-D technology in theaters and on television has drifted in and out of mainstream popularity. But, whether you’ve used them for the big screen or at home in front …

Believe it or not, a tank of cleaning fluid buried underground is telling us about what goes on at the center of the Sun. and the startling news is that the Sun may have stopped burning, albeit temporarily. According to theory, the nuclear reaction include the Sun should produce atomic particles known as neutrinos, which escape directly into space and …

The ancient Greeks called them ‘hairy stars’. In fact, they were seeing comets-heavenly bodies with long, streaming tails that travel endlessly around the sun. Before they were understood, comets were believed to foretell plagues, war and death. A comet was seen over Rome after the murder of Julius Caesar in 44 B.C. Another, Halley’s comet, appeared over Europe in 1066, …

Did you know that whales, dolphins, and porpoises use a number of different sounds to communicate. They have one of the most highly developed animal ‘languages’. The finback whale produces a very low-pitched sound which it repeats over and over again-scientists think that the finback uses this sound to talk to other whales a long distance away.

Yes, an electric field affects plant growth. In the presence of an electric field, the height of the stem and the length of the roots are more than those without an electric field. The change in growth rate depends on electric field, temperature and humidity. Experiments show that if an electric field intensity of 25 kv/m is applied and temperature …

Not necessarily. Although many types of wine, particularly red ones, improve with age, there are some which do not keep so well, and may become unpleasant if kept for too long. Also, it has became fashionable recently to drink some wines when they are ‘new’ this means that the wine has been made from grapes harvested in the same year. …

Before we can answer this question, we must look at exactly what a comet is. As you probably know, a comet looks rather like a star with a long, milky ‘tail’ stretching across the sky. In fact these ‘tails’ are not tails at all because they always point away from the sun and do not trail behind. A comet seems …