Archives September 2013

The sun travels across the sky at the rate of 15 degrees per hour (reappearing at a given point after one day) and the shadow that it casts moves at a similar rate. In sunny climes the shadow has been used as a clock. The most ancient clock was the vertical obelisk. This tapering column, rather like Cleopatra's Needle in London, cast a shadow that varied in its length and orientation as the day progressed. The Egyptians had a small, portable shadow clock. It consisted of a T-shaped bar that lay on the ground, except that close to the shorter crossbar was a 90-degree bend that lifted the crossbar above the long horizontal stem so that its shadow would fall on the stem. The long stem was pointed directly toward the west point on the horizon in the morning. At noon, it was pointed in the reverse direction, toward the more...

Co-education means education of boys and girls together in the same school or college at the same time. In india it has recently become popular. Co-education is not a new thing for us. In the good old days when 'Ashrams' were the seats of learning, co-education was in practice. In the Hindu scriptures, old records and legends we find a number of examples which show that co-education was all over the country. Practice continued till the coming of Muslims in India. The Purdah system put an end to co-education. From the very beginning voices have been raised against co- education. Stephen Lealock, an American educationist declares, "Men cannot read when women are around". There are many charges against Co-education. First, it lowers the tone of discipline. Secondly, it brings about a shift in the minds of students. Learning goes to the background and 'sex attraction reigns supreme'. Thirdly, it creates more...

I live at Shatpura, a small village in Moradabad district. The nearest town is Moradabad, some 25 km away. It is a small village, where about 225 families live. It is located in the midst of vast fields on all sides. Our village is flanked by the national highway on the north and in the south is the River Ganga, barely 1 km from the heart of the village. To go to town, we have to tread about 5 km long kuchcha way to reach the national highway from where we can get a transport. My village has a few graduates, some of whom are school teachers in a high school in the neighboring village.  Others travel by bus to travel by bus to Moradabad or Rampur to earn their living. There is a post office, a charitable dispensary and a health centre nearby. The population of my village is more...

Although the first zoom lens was invented in 1901 by Clile C. Alien, its popularity in sales terms only came in the late 1980s. Prior to this the fixed-focus lens was the standard; however, this was pushed aside because of the physical effort required to photograph different- sized subjects. With a fixed-focus lens, the only way to adjust the amount captured in a photograph is to physically move backward or forward with the camera. A zoom lens works by allowing the photographer to widen or shorten the focal length, which increases or decreases the magnification of the subject. The focal length is the distance between the lens and the point in the camera at which the light rays converge. Changing this length allows you to zoom in and out when taking a photograph. There are many different designs of zoom lens. Some may be composed of up to thirty individual more...

The last two decades (1981-1999) witnessed the emergence of a new fatal disease in short called "AIDS". The Acquired Immune Deficiency Syndromes virus infects the blood stream through sexual intercourse with a person having HIV, by transfusion of blood from a person positive to HIV, sharing injection needle with AIDS positive person or from the infected mother's blood to the child during pregnancy period. Once this deadly virus (HIV) enters the blood of a man or woman, he or she, is bound to die.  At the beginning of disease no one knew what was destroying the immune systems to otherwise healthy men. But after sometimes it was detected as a newly discovered "retrovirus". It was eventually called the "human immune efficiency virus" or HIV. The scientists, a after long researches, mapped out the genes of HIV and discovered which parts of this gene are constant and which are variable. They more...

“I soon learned that it did not require a great brain to do original research." Julius Axelrod Despite earning a degree in biology, American biochemist Julius Axelrod (1912-2004) was rejected from all the medical schools he applied to and so got a laboratory technician job in New York's public health department, looking at vitamins in food. He attended night school to get a master's degree in science in 1942, then worked under scientist Bernard Brodie (1909-1989) at Goldwater Memorial Hospital in 1946. During the 1940s the use of nonaspirin-based pain analgesics was being linked to the blood-poisoning condition methemoglobinemia. Axelrod and Brodie wanted to find out why Their detailed research found acetanilde, the main ingredient in many of these products, degraded into the blood toxin aniline. They suggested this was the most likely cause. They also discovered that one of its breakdown products also worked to kill pain in the more...

Micro-Electro-Mechanical Systems, or MEMS, are specialized silicon chips that incorporate not only miniaturized  electronic  circuits  (the "electro" component) but also a "mechanical" part, such as tiny arms, gears, or springs. These chips, therefore, may possess not only the ability to process data, but also, etched into its surface, the ability to collect data in the form of some kind of sensor. Needless to say, the sensors are tiny, going down to the scale of millionths of a meter, or micrometers. The term MEMS is itself thought to have arisen as a consequence of a 1987 gathering, called the Micro Robots and Teleoperators Workshop, conducted by the International Electrical and Electronics Engineers." Later, in 1988, a reliable method of bonding silicon components onto silicon chips was demonstrated. Controllers in some video games, for example, utilize tiny accelerometers within their control pods to measure tilt, shock, and acceleration. While this is obviously more...

"Many remains of....stone architecture exhibit forms [that imitate] construction in wood." John Capotosto, writer  Before the discovery of metallurgy, long before plastics, the materials that Stone Age man used were those that he found around him in nature: stone, mud, bone, and of course wood. Wood is an extremely important material, having numerous useful properties; it floats, it burns, and it can be shaped relatively easily into a variety of different objects. The craft of shaping and using wood—carpentry—has its roots in prehistoric times. Early woodwork consisted of the use of wood for basic tools, but there is also archeological evidence that Neanderthals were shaping wood into new forms as long ago as the middle Paleolithic (Old Stone Age, 300,000 to 30,000 years ago), using tools made from flint and stone. In this way many useful things were created from wood, including fire-hardened spears and logs hollowed out to create more...

It was one day tour. We did not fix any destination. We started in the morning. "Be ready" was our motto. We believed to meet some adventure on our way. We caught our train. At Jogeswari the train stopped. We had got down to catch another train. We did not wait for another train. We decided to see the caves. (Wished to pass sometime there). It was 4 o'clock. Now we decided to see the Fort of Bassein. But on the second thought we decided to visit Conary Caves,  We walked, we strode, and we ran. We crossed a stream. After some time we reached the foot of caves. Some of us separated at the fork of two roads. Now the romance began. We lost our way. It was a big forest. I had no knowledge of the paths. I climbed up and up. There was no end to our more...

On May 6, 1840, in the greatest single reform of the English postal system since its inception in 1510, the world's first prepaid adhesive postage stamp, the Penny Black, was issued. The stamp ushered in the era of prepaid post and was instrumental in lowering postal rates. By 1856 the number of letters posted annually in Britain had grown to almost 400 million, compared to a mere 76 million in 1839. The Penny Black, graced by the profile of England's young Queen Victoria, was designed by postal service employee Rowland Hill (1795-1879). In 1837 Hill authored and circulated a pamphlet titled Post Office Reform: Its Importance & Practicality, in which he tackled the reasons for the complexity and often prohibitive costs involved in delivering Britain's mail. Prior to 1840, prepaid postage was purely voluntary. However, where the letter was not already paid for, the cost of delivering it had to more...