Archives March 2013

The dramatic rise of the textiles industry in Britain was one of the most important aspects of the world's first Industrial Revolution. Machines had been spinning yarn rapidly and effectively since the 1760s, but the mechanization of weaving did not take hold properly until after 1810. It began when Edmund Cartwright (1743-1823) patented the first powered loom in 1785. Handlooms had become commonplace by the eighteenth century. They are relatively slow, and each one requires at least one person's full attention. In its basic form, a powered loom is simply a mechanized, automated version of a handloom. It can produce cloth faster than a handloom, and a single person can watch several or many machines. Power for Cartwright's looms was originally supplied by waterwheels, via a drive shaft and belts and gears. But steam power increasingly took the place of waterpower during the nineteenth century, because steam-powered factories could be more...

"A two-year-old is kind of like having a blender, but you don't have a top for it." Jerry Seinfeld, American actor and comedian Although ubiquitous in modern kitchens, the blender started life as a tool for the soft drinks industry, designed to mix mailed milkshakes. By the 1920s both milkshakes and malted milk drinks were extremely popular. However, malted milk powder was developed as a hot drink and so often clumped together when mixed with cold milk, resulting in a lumpy milkshake. This problem was overcome in 1922 when Stephen Poplawski (1885-1956) invented the blender. His design had small spinning blades, driven by an electric motor, at the bottom of a tall container into which all the ingredients would be added and mixed. The device also resulted in a lighter, frothy drink, forever changing the consistency of milkshakes and at the same time paving the way for the smoothie. With more...

"Absolute protection from the rascals with the dark lanterns and jimmies." New York Times, March 8, 1890 On March 8, 1890, the New York Times published an article about two rival security companies. One, the Holmes Electric Protective Company, had been selling alarms for more than thirty years. The other had been doing so for just eighteen months. Now the presidents of the two companies were at war. The president of the Electric Protective Company was Edwin Holmes, who regarded himself as having pioneered the electric burglar alarm. He had enjoyed a monopoly over the home security market for many years and viewed his opponents at the Metropolitan Burglar-Alarm Company as thieves who had stolen his invention. In fact, he had bought the patent for the burglar alarm from Augustus R. Pope in 1857. Pope's original patent document of 1853 shows a simple system of magnetic contacts and switches attached to more...

Millions have turned to laser-assisted in situ keratomileusis (LASIK) to correct myopia, hyperopia, and astigmatism, and do away with wearing glasses. In the 1950s, Spanish ophthalmologist Jose Barraquer devised a method for surgically changing the shape of the cornea. His technique was developed further by Russian ophthalmologist and eye surgeon Svyatoslav Fyodorov, who created radial keratotomy while treating a boy whose glasses had smashed into his eye after a fall. He made several radial incisions from the pupil to the edge of the cornea to remove the glass. Once the cornea had healed, the boy's eyesight was much better. Fyodorov's success fueled much interest in refractive surgery. In 1968, work was going on at the University of California, where Indian physicist Mani Lal Bhaumik and colleagues developed an excimer laser. This creates new molecules when xenon, argon, or krypton gases are excited. In 1973, Bhaumik told the world of the more...

Most types of clocks rely on the oscillation of a solid body, be it a pendulum, a balance-wheel, or a quartz crystal, but each suffers from the effects of temperature, pressure, and gravity. Time measuring devices have also depended on the spin of the Earth, but these suffer from seasonal effects and tidal friction. Atoms, however, vibrate a fixed number of times per second. Both the-U.S. National Bureau of Standards and the United Kingdom's National Physics Laboratory tried to take advantage of these vibrations. In 1949 the Americans built a quartz clock that was synchronized by the 24-GHz vibrations of low-pressure gaseous ammonium molecules. The British, under the leadership of physicist Louis Essen (1908-1997), used the oscillations of an electrical circuit synchronized to the vibrations of caesium atoms, the first caesium clock being built in 1955. The caesium was kept in a tuneable microwave cavity and the clock relied on more...

The oldest boomerang so far found was discovered in a cave in the Carpathian Mountains in southern Poland and is believed to be date from 18,000 B.C.E. The practice of throwing wood has also been illustrated in North African rock paintings that date from the Neolithic Age (approximately 6000 B.C.E.). The wood thrown consists variously of a "throwing club," where the effect is concentrated at one end, or a "throwing stick," a sharpened, straight rod of hard wood that rotates, or a boomerang, which developed from these into a specialized form and has a return throw. Ancient tribes in Europe are said to have used a throwing axe; in Egypt a special type of curved stick was used by the Pharaohs for hunting birds. The use of throwing woods is thought to have spread throughout North Africa from Egypt to the Atlantic. Boomerangs are most commonly associated with Australian Aborigines. more...

India is the seventh largest country in the world. The Government of India takes suitable steps for the welfare of the citizens, such as building roads, hospitals and schools; providing electricity and water supplies; maintaining law and order in the country and making the life of the citizens happy and prosperous. One such step is the distribution of basic necessities of life. The public distribution system or the fair price shop is a means by which the government provides various articles of daily use to the citizens   at reasonable prices. The articles sold here include sugar, wheat, wheat flour, vegetable oil, pulses,  cereals, clothes, kerosene oil etc. Those things are specifically sold at a fair price shop which is difficult to get in the open market. A citizen requires a ration card to buy articles from a fair price shop. For it, he has to register himself with the more...

"The straw was removed, and the grain along with the chaff was swept up, and placed in a basket." John Carter, How to use a Flail. The flail is one of the oldest agricultural tools known to man, having been in use for more than 5,000 years. It has served as a symbol of power and even as a weapon. Despite the introduction of motor-driven harvesting machines in the nineteenth century, it is still used to this day in some parts of the world. Its primary function is for threshing—the forced separation of grain from the parent plant. It is not clear where the flail originated, but it was certainly used in ancient Egypt. The flail is essentially a handle—called the staff—coupled at one end by a length of leather to the end of a second shorter rod. The staff is held at the free end and the rod is more...

It is said some are born great, some become great and to some greatness is thrust upon. We see in every society, in every community, in every group of people, there is bound to be someone who emerges above others and who acts as a guide or a lead. The majority of people in this world are to be led, and to be shown the path they ought to tread. But a few are off from the rest and they can rule over the rest.  It is true that leaders are born, no doubt, but training may also play a vital role in developing qualities of leadership. Those who are born leaders feel an inner compulsion to perform great tasks and they successfully accomplish them. Born leaders need no training and they shape the destiny of others. Columbus was a born leader who had the qualities of leadership in undertaking more...

Outline : Working hours : 10 a.m. to 4 p.m. A 45-minute break at p.m. Lunch time for some, play time for others—three friends and 1. Firs three days a week—join a larger group to play outdoor games. Next two days a week—indoor games half day's work. A few go home at one. some  do homework to ensure/all holiday on Sunday-lunch break period is the  best part of the school day. Everyone enjoys it. I am a student of XII class in a well-known senior secondary school The school working hours are from 10.00 a.m. to 4.00 p.m. The first bell goes at 10 a.m. Then follows the morning assembly. There are four periods up to 1.00 a.m. We study sincerely. Then, there is a lunch break of 45 minutes. All of us wait impatiently for this break. It is a must after hard labour and serious teaching of four more...