Archives April 2013

"It has often proved true that the dream of yesterday is the hope of today, and the reality of tomorrow."  Dr. Robert Goddard, American scientist Robert Goddard (1882-1945) gave serious thought to how we might get to the Moon. Despite being met with ridicule, what he gave to rocketry is still being used today. Using mathematics, Goddard worked out the energy-to-weight ratios of various fuels. This showed that gunpowder would never be powerful enough to lift a rocket into space. Also, to burn fuel in a vacuum, a rocket would have to carry it^ own oxygen supply to get around these problems, Goddard used gasoline as a fuel and mixed it with liquid oxygen. Oxygen as a gas takes up a lot of space, but as a liquid it gives the rocket a lot of energy with much less weight and volume. In 1914 Goddard patented the first liquid-fueled rocket. more...

There are four seasons in our country. Summer is one of them. It comes in the month of April and lasts till July In England, the summer is a happy time. But in India it is very hot. It is so hot in India that all schools, colleges and some of the Government offices and courts are closed for summer vacation.  In summer morning is the busiest time. People are seen walking about doing their business. The rich people who have no work go out for a walk. Only lazy people remain lying on their beds. Some boys and men go out for a bath in the river, canal or tank. The market is busy the people try to finish ail their work as quickly as possible. At noon, the towns and cities look deserted. The shopkeepers are dozing. There are few people on the road. All kinds of work more...

In one's life span a person has opportunity to visit many places and some of them leave a lasting impression. A visit to the radio station is always memorable. It is an important place which one cannot visit whenever one likes. There are so many restrictions in entering the station. There is a procedure for visiting the place. Luckily, I had a chance to go to the All India Radio Station, Delhi, recently. My friend brought two passes, one for visiting the radio station and other for admission to one of his programmes. This programme was broadcast in the presence of an invited audience.  I accompanied my friend early in the morning. We reached the radio station at half past eight. It is a big and beautiful building, neat and attractive. It has a large reception hall. One can hardly keep account of the rooms. There are many signboards and more...

Beta blockers are drugs that block the stimulating action of noradrenaline—the "fight or flight" hormone—thereby reducing the force of the heartbeat and the workload of the heart. Today they are widely used to treat angina, high blood pressure, and irregular heart rhythms, and to improve heart muscle function in cardiomyopathies. Beta blockers were developed in 1956 by Sir James Black [b. 1924), a Scottish doctor working for ICI in the United Kingdom. Black had personal as well as professional reasons for his interest in cardiovascular disease. His father had a fatal heart attack following a car accident, making Black ponder the role of stress in producing adrenaline, angina, and heart attacks. At the time, many of the drugs used to treat angina were vasodilators (causing dilation of the blood vessels), in particular nitrites, which increased the blood supply, and therefore the amount of oxygen to the heart. However, these caused more...

"As a physical philosopher be has no superior in our country [at least] among the young men." Geologist Benjamen Silliman on Joseph Henry When American Joseph Henry (1797-1878) first became interested in science at the age of sixteen, he found electricity fascinating and began experimenting with electromagnets. Wires carrying electricity produce weak magnetic fields around them. If, however, the wire is coiled many times around a metal such as iron, the effect is magnified and the resulting magnetic field is much stronger. The first electromagnets were coiled very loosely to prevent the current-carrying wires touching and causing an electrical short circuit. Henry was the first to use an insulating cover for the wires so that they could be wrapped more tightly and in many layers, multiplying the effect. Henry's first insulation for wires was tediously made from strips of his wife's petticoats. The material of the insulator has to resist more...

Leisure means spare time which we get after our day's long work. It is our free time in which we are free to do anything we like. There is no pressure of any type and we wish to enjoy it to the fullest. But it is always wise to use our leisure meaningfully. We should value our leisure, take it seriously and make the most of it. Holidays bring us more leisure than the working days. We are living in modern times, facing the problems of modernity at every moment. Our life has become so busy, so fast that we always remain in hurry and pressure of work. In this fast life, leisure plays a significant role because it relaxes  us and brings immense joy. Our life becomes dull if there will be no leisure, no spare time. Here we can quote the feelings of a great English poet Davies more...

"Billy... identified [the lock] as a Chubb rather than a Bramah, which is reputably unpickable." Frederick Forsyth, The Fourth Protocol (1984) The British inventor Joseph Bramah (1748-1814) patented eighteen new ideas during his lifetime, including the fountain pen, fire engine, and beer hand-pump, but remarkably he is most famous for his safety locks. His lock design had ingeniously included notched sliders that made it nearly impossible to pick. Bramah was so sure of his locks that he offered a cash prize to anyone who could pick it open. The Challenge Lock, as it became known, caught media attention and boosted the profile of his company as the lock resisted all effort for at least fifty years; the money remained unclaimed during Bramah's lifetime. The lock was eventually opened by A. C. Hobbs, an American, although it took him sixteen days to do so. The original of the famous lock can more...

Defenses have been constructed for thousands of years. Bronze and Iron Age hillforts took advantage of natural hills for defense purposes, and the Romans built the Saxon Shore Forts along the southeast coast of Britain to deter invasion. The word fort is derived from the Latin fortis meaning "strong" and many military installations are known as forts. The term fortification also refers to improving other defenses such as city walls. Permanent fortifications were built of enduring materials, but field fortifications needed little preparation, using earth, timber, or sandbags. The arrival of cannons in the fourteenth century made medieval fortifications obsolete.  Later constructions included ditches and earth ramparts to absorb the energy of cannon fire. Explosive shells in the nineteenth century led to a further evolution; the profile of the fort became lower, surrounded by an open sloping area that eliminated cover for the enemy. The fort's entry point was a more...

The spring season extends from the middle of February to the second week of April. So, the duration of spring season is very short. The spring is my favourite season and I like it for more than one reason. First, during this season, a fine atmosphere prevails. The weather is pleasant. Secondly, it is the season of greenery and flowers. Thirdly, plants and trees put on fresh leaves and the gardens charm the eye with a variety of beautiful I flowers. The whole of nature looks very nice with fresh and new shoots, leaves and grasses. Flower plants burst into beautiful blossoms now. Variety of flowers blossom and are seen on the trees like palash, krishnachura, radhachura, ashok, shimul, bakul and champa etc. During this season, the wind blows from the south. Different singing birds, like the cuckoo, sing sweetly here and there. Many important festivals, such as Saraswati Puja, more...

Shivaji was the founder of Maratha Empire in India. He was the first Hindu to establish a Hindu empire after the Muslim rule. Shivaji was born in 1627 at Poona. His father Shahji Bhonsle was a Jaqirdar. He was in the service of the King of Bijapur. Shivaji lived at Bijapur. The charge of Shivaji's education fell in the hands of a Brahmin named Dadaji. His mother Jijaji Bai was a very pious lady. Shivaji got best qualities of his character from her. He could not learn how to read and write. But he became skilful in all sorts of manly games, when he became young, he was master of riding and arts of war and fighting. Dadaji used to read to him the stories of the Ramavana and Mahabharata. Thus the fire of patriotism was kindled in him when he was quite young. The stories of the acts of more...