Archives December 2013

“To see barges waiting ...at a lock affords a fine lesson in how easily the world may be taken." Robert Louis Stevenson, An Inland Voyage (1878) Locks interrupt a canal or river with stepped stretches of still water, thus reducing currents in the waterway and conserving deep water for passage. The forerunner of today's lock was the flash lock, already in use by the first century B.C.E. in China, whereby part of a dam would be temporarily opened to allow passage of a vessel. Those traveling downstream were carried on the resulting surge of water, whereas those sailing in the opposite direction hauled the vessel against the torrent. Such an arrangement was dangerous and resulted in the loss of large quantities of water downstream for every vessel passing, a circumstance not appreciated by mill owners reliant on the supply. In 984, during the construction of China's Grand Canal, engineer Qiao more...

Obedience is a great virtue. The lesson of obedience is an important one. It may be both personal and social. It is a great moral virtue and a sure sign of refined personality. Obedience is at the root of the progress of this world. Our parents love us. They wish our good. They always work for our welfare. They are glad if we are great and good. Whatever they bid us to do is for our own good. We should obey them and do what they wish us to do. The young in a family are expected to follow the advice of their elders. If they refuse to obey, the institution of the family ceases to exist. Now what starts well at home shows better in the society. For, home is the breeding ground of the values of life. An obedient child learns to respect his teachers, obeys the rules more...

There can be few people who have not encountered this remarkable product. Assumed by some to have been a spin-off from wartime, military technology, and therefore named "War Department—1940," the title actually relates to the number of attempts it took the inventors of this water displacing (WD) chemical to perfect the product. It was at a lab in San Diego, California, in 1953, that the Rocket Chemical Company and its three personnel embarked on their mission to create a range of rust- prevention and degreasing products for use in the aerospace industry. After thirty-nine "almosts," they succeeded. The aerospace contractor Convair bought the chemical for use as a corrosion inhibitor on its Atlas missiles, and other wholesale orders soon followed. Rocket Chemical Company employees had for some time been taking small amounts of the petrochemical-based product home for their personal use. Company founder and chemist Norm Larsen (1923-1970), suspecting that more...

"Wrong and inappropriate use has caused LSD to become my problem child." Albert Hofmann Lysergic acid diethylamide (LSD) is a powerful psychedelic drug. While now commonly associated with 1960s dropout youth culture, it was heralded as a wonder drug in the 1940s and 1950s and was used to treat thousands of psychiatric patients. Swiss chemist Albert Hofmann (1906-2008) first synthesized LSD in 1938, expecting it to be useful as a medicinal stimulant. In 1943 he returned to studying it and after experiencing some pleasant sensations while working with the drug. .he took a dose of 0.25 mg. Hofmann bicycled home and began to experience its psychedelic effects, the world's first "trip." He reported that the morning after he felt entirely renewed and that his senses were "vibrating in a condition of highest sensitivity." Today LSD is mainly taken as a recreational drug for its psychological effects. Common accounts are of more...

Scoring tips The following tips would certainly help you in scoring well in the exam: Go through previous years’ question papers along with solutions, and analyse the subject pattern and focus on those subjects which have maximum weightage. Books can further be divided into two categories: Books that deal with the fundamentals and focus on conceptual clarity. Here textbooks by reputed publishers are a must. Books that provide a great deal of difficult and time-consuming questions and are used essentially as practice material. Do not rely on just one book for a topic; instead consult a couple of books for the same topic. Prepare notes after completing each chapter. Practise the maximum number of questions possible on a given topic. This certainly strengthens your preparation. Keep in mind that those topics which are not in GATE syllabus could be certainly left out. Make a list of topics in which you more...

"None of our mordern craftsmen [except Alberti] has known how to write these subject..." Giorgio Vasari, Lives of the Artists (1550) Devised by Leon Battista Alberti (1404-1472), the anemometer was a simple instrument to measure wind speed. It had a rectangular metal plate attached to a horizontal axis with a hinge, so that in the wind the metal plate lifted, giving an indication of relative wind speed that could be measured crudely on a curved scale bar below the plate. In light winds, the plate would move slightly on its hinge; in stronger winds, the plate would lift further. Alberti describes and illustrates this device in his book, The Pleasure of Mathematics (1450).' The well-educated son of a wealthy merchant, Albert! was an accomplished artist, athlete, horserider, musician, mathematician, cryptographer (inventing the cipher disc), classicist, writer, cleric, and architect. He was a true Renaissance polymath, created by the intellectual culture more...

"Our earth is degenerate in these latter days.... The end of the world is evidently approaching? Inscription on an Assyrian tablet About 5,000 years ago, the Sumerians of ancient Mesopotamia invented humankind's first writing system. Having already established the world's first true civilization by introducing agriculture and domesticating cattle, they decided that it was more efficient to record their economic transactions in writing rather than use tokens to represent the number of beasts and the amount of harvest they traded. Their initial use of simple pictograms (drawings representing actual things) quickly developed into a complex system of symbols where items were illustrated by one sign and their volume by another. The Sumerians' innovation was not only used for commercial purposes, but also extended to phonetic—rather than wholly pictographic—ideograms that expressed concepts such as deity and royalty as well as thoughts. As the symbols evolved, the notes that were recorded on more...

"We think the iPhone is a 'game changer'... it will change how people think about... handsets." Randall Stephenson, CEO of AT&T Announced in January 2007 and eagerly awaited, the Apple iPhone could play music, take photographs, browse the internet, send e-mail, play movies, and store up to 8 gigabytes of information. It also had Wi-Fi capabilities, a calculator, calendar, and notepad, and operated via a nifty touch-screen mechanism. And it could make a telephone call. With its large screen, lack of buttons, and sleek appearance, the iPhone stood out in design terms alone—unlike its competitors, it did not look like a phone. What is more, the touch screen was designed to be operated by a finger, so it was no longer necessary to find the stylus required by other models. However, the iPhone did not perform as well as expected, with Apple taking only a 5 percent share of the more...