Science Projects And Inventions

"If you die in an elevator, be sure to push the Up button" Sam Levenson, American author and humorist Who would now dare to travel in a high-rise elevator if their life literally hung by the elevator cable? In 1852 Maize and Burns, a bedstead-making firm in Yonkers, New York, was faced with that problem— how to hoist its bedsteads up to the top floor of its premises without risk of them crashing down if the rope broke. Elisha Otis (1811-1861), the firm's master mechanic, had experience of designing safety brakes for railway wagons. He devised a system involving a platform that could move freely within an elevator shaft unless there was a cable failure, whereupon a tough steel-wagon spring would mesh with a ratchet in such a way as to catch and hold the heavy platform. Otis left the company to market his invention. Interest was slow at first, more...

"All the learnin' my father paid for was a bit O' birch at one end and an alphabet at the other." George Eliot, author In 1999, Yale Egyptologist John Darnell revealed to the world that the 4,000-year-old graffiti he had discovered at Wadi el Hoi in Egypt's western desert represented humankind's oldest phonetic alphabet. Incorporating elements of earlier hieroglyphs and later Semitic letters, Darnell's discovery contradicted the long-held belief that alphabetic writing originated in the area of Canaan (modern-day Israel and the West Bank) midway through the second millennium B.C.E. Nevertheless, the writings—carved into soft limestone cliff—are thought to be the work of Canaanites, or rather Semitic-speaking mercenaries serving in the Egyptian army during the early Middle Kingdom (c, 2050 B.C.E.-c. 1780 B.C.E). Presumably developed as a simplified version of Egyptian hieroglyphs, the alphabet enabled those soldiers—as well as ordinary people in general—to record their thoughts and to read those of more...

A few miles south of Manhattan, New York, is a town called Travis. Up until 1930, that town was known as Linoleumville—the home of America's first linoleum factory, owned by British inventor Frederick Walton. Walton's love affair with linoleum began in the 1850s, when, as the story goes, he noticed a skin that had appeared around the top of an old paint can. This skin was the result of a simple reaction occurring between linseed oil in the paint and oxygen in the air. Most oil-based paints contain linseed oil; you've probably peeled off the rubbery solid that forms around the rim without even thinking about it. But Walton couldn't stop thinking about it. He embarked on a series of experiments that would eventually lead to a process for manufacturing floor tiles from linseed oil. His road to success was a rocky one. In 1860, he filed a patent for more...

Fireworks, familiar now in sound-and-light shows on dark evenings, to celebrate festivals and to entertain, were invented in China around 1,000 years ago, following the invention of gunpowder in the first century C.E. Bamboo tubes, filled with gunpowder, were thrown onto fires to create explosions at religious festivals, perhaps in the belief that the noise they made would scare off evil spirits. It is highly likely that some of these little bombs shot like rockets out of the fire, propelled by the gases they produced. The next step seems likely to have been to attach such charged bamboo tubes to sticks and fire them with bows. The earliest evidence of devices that could be described as firework rockets comes from a written report of the battle of Kai-Keng in 1232 during the war between China and Mongolia, in which the Chinese attacked with "arrows of flying fire." After Kai-Keng, the more...

"One of the marvels of the age is the new quick freeze process... time ceases to exist for foods" Better Homes and Gardens, September 1930 In 1912 Clarence Birdseye (1886-1956) was working as a field biologist in northern Canada when he was taught by Inuit people how to preserve fish by freezing under very thick ice at around -40°F (-4Q°C). Frozen almost instantly, it tasted fresh when thawed days or weeks later. Birdseye realized that this fish was fresher than that sold in the fish markets in New York, which had also been frozen but slowly and at higher temperatures. He also saw that when food was frozen quickly, only small ice crystals formed in the cells, causing less damage to the texture. Frozen food will keep for several months, so long as it is stored at a constant temperature no higher than -0.4°F (-18°C). Birdseye joined the Clothel Refrigerating more...

Modern medicine has come a long way. We can treat pneumonia, hypertension, diabetes, and even heart failure—but certain genetic diseases have proved more difficult to deal with. That may change in the near future with the application of techniques pioneered by Paul Zamecnik (b. 1912). The use of genetic manipulation has had a place in medicine for quite some time in the form of recombinant DNA. This technique has been the source of many medicines, but is not really manipulation of genetic material in an individual. Zamecnik, though, may have revolutionized gene therapy, not by inserting new genes into an individual, but by blocking the genes that were already there. While studying a virus prone to causing certain cancers in chickens, Zamecnik realized that rather than adding a gene, he could manipulate the viral RNA so that it would not be able to reproduce. He figured he could take advantage more...

“I’ve come to believe that each of us has a personal calling that is as unique as a fingerprint." Oprah Winfrey, O Magazine (September 2002) When two boys were brutally murdered near Buenos Aires in 1892, the police quickly named their mother's suitor, a man called Velasquez, as the only suspect. However, only a few days later police officer Juan Vucetich (1858-1925) proved beyond doubt that the murderer was, in fact, Francisca Rojas, the mother. Working at the La Plata Police Office of Identification and Statistics, Vucetich's task was to identify criminals using anthropometry. Less than a decade previously, Frenchman Alphonse Bertillon had established that the measurements of certain parts of the human body never alter, therefore giving each individual—in addition to their personality traits and peculiar markings such as tattoos and scars—a distinctive anthropometric identity. His approach, named "Bertillonage," was widely adopted by police forces as a more reliable more...

Neoprene—trade name for polychloroprene—is a synthetic rubber produced from chloroprene by polymerization (changing short chains of molecules to longer chains). Chloroprene is a liquid that when polymerized forms a solid, rubbery substance. When compared with natural rubber, it is lighter, does not perish, is a better thermal insulator, and is chemically inert. Neoprene was invented in 1930 by Wallace Carothers (1896-1937), and by 1931 it had become the first mass-produced synthetic rubber compound. It is commonly used in wetsuits, car fan belts, gaskets, hoses, and corrosion-resistant coatings. When used for wet suits, the air spaces in the neoprene are filled with nitrogen to increase its insulation properties. This also makes the material more buoyant. More recently, it has become a- fashionable material for lifestyle accessories, including laptop covers, iPod holders, pouches for remote controls, and even jewelry. The development of synthetic rubber began at DuPont, the U.S. chemical company. It more...

'Let us have wine and women,  mirth and laughter/Sermons- and soda-water the day after." Lord Byron, Don Juan Joseph Priestley (1733-1804) grew up near a brewery in Yorkshire, England, and as a teenager saw carbon dioxide gas "floating" above deposits of fermenting grain. In 1771 this clergyman, philosopher, and chemist began to inject carbon dioxide, what he called "fixed air," into small containers of water uncontaminated by the surrounding air. By agitating the mixture for thirty minutes he was able to cause the water to absorb its own volume of carbon dioxide, and so he created the world's first drinkable glass of carbonated water. In 1772 Priestley wrote a book detailing in part how he thought carbonated water could be used to retard food spoilage and reduce the incidence of scurvy on long ocean voyages. He also wrote a paper entitled Directions for Impregnating Water with Fixed Air. Priestley's considerable more...

"Peter Henlein... makes from a little iron a pocket clock with a lot of wheels." Johannes Cocleus, historian The world's first portable timepiece, which came to be known as a "pocket-clocke," was made in Nuremberg, Germany, between 1504 and 1508 by the former apprentice locksmith and clockmaker Peter Henlein (c. 1479-1542). The miniaturization of timepieces began with the invention of the coiled spring in Italy in the late 1450s along with the development of various escapement mechanisms. However, the real breakthrough proved to be Henlein's invention of the balance spring, which greatly improved the precision of a watch's spring-driven interior. Henlein's new pocket watch measured only a few inches in diameter, chimed on the hour, and could run for up to forty hours before it required rewinding. It was driven by scaled-down steel wheels and hand- forged springs that, despite representing a huge technological leap forward, were nonetheless persistently inaccurate. more...