Science Projects And Inventions

Rail travel is one of the safest ways to get around in the modern age. The pioneer responsible for much of this safety record was the visionary inventor and industrialist George Westinghouse (1846-1914). Before he invented his revolutionary air brake, slowing and stopping a train was an exercise fraught with risk. Each separate car of the train needed its own brakeman to manually operate brakes on its own set of wheels. Accidents caused by uncoordinated braking were frequent and Westinghouse realized that the poor safety of trains was holding up the whole industrialization of the United States. He spent several years working on a replacement for brakemen's manual labor. Various models failed until, in 1868, he found a solution. He placed an air compressor inside the train driver's cabin and connected long air hoses to it. These hoses traveled the length of the train and were attached to brakes on more...

The cluster bomb has courted controversy since its induction in modern warfare in 1939. A conventional bomb consists of a single container carrying an explosive charge that is designed to explode upon impact. The cluster bomb differs through the addition of an outer casing carrying dozens of small bomblets. The casing splits open in mid-air, releasing a shower of smaller bomblets that impact over a broad area. Often dropped by parachute, cluster bombs are highly versatile, if not particularly accurate. They can wreak havoc on soft or unarmored targets such as airfields and formations of men; cluster bombs containing shrapnel are able to pierce armored tanks and penetrate concrete. Cluster bombs really came to the fore during the Vietnam War. U.S. forces carpet- bombed the dense forests of Vietnam, Laos, and Cambodia with cluster bombs carrying chemical weapons such as napalm. The bombs were designed to set fire to the more...

"When the plumbers and sanitary engineers had done their work... diseases began to vanish." Lewis Thomas, medical researcher and essayist It was probably more the need to get rid of foul smells than an understanding of the health hazards of human waste that led to the first proper sewage systems. While most early settlements grew up next to natural waterways—-into which waste from latrines was readily channeled—the emergence of major cities exposed the inadequacy of this approach. Early civilizations, like that of the Babylonians, dug cesspits below floor level in their houses and created crude drainage systems for removing storm water. But it was not until around 2500 B.C.E. in the Indus Valley that networks of precisely made brick-lined sewage drains were constructed along the streets to convey waste from homes. Toilets in homes on the street side were connected directly to these street sewers and were flushed manually with more...

"I wanted to work in the visible spectrum... and everybody else was working in the infrared." Nick Holonyak The LED (light-emitting- diode) is a semiconductor device. All semiconductors have a variable ability to conduct electric current because of impurities (caused by trace chemical additives) in their structure. An N-type impurity adds an extra electron to the semiconductor, and a P-type impurity provides an electron hole. Electrons, negatively charged particles, naturally move from areas with many electrons (negative) to areas with few electrons (positive). In a diode, an N-type material is placed next to a. P-type one, and the two are sandwiched between electrodes. This setup only allows electric current (a stream of electrons) to flow in one direction, from the N-type side's electrode to the P-type side's electrode. When an electron drops into an electron hole, it releases energy in the form of a photon. As a result, when electrons more...

Being a woman in science in the early 1900s was difficult for American neurophysiologist Ida Hyde (1857-1945). Born in Davenport, Iowa, to German immigrant parents, she struggled to find a university that would accept her. She eventually earned a bachelor's degree at Cornell University and later became the first woman to earn a PhD in science at the University of Heidelberg, in Germany. Despite this, Hyde was still not acknowledged for her invention of the microelectrode until after her death. Since then, the microelectrode has revolutionized neuro-physiology. Hyde's electrode was so small that at the time her methods were among the first capable of studying single cells. Hyde's research focused on the breathing mechanism and nervous systems of a range of organisms, from grasshoppers to humans. During her research, she invented the microelectrode so that she could deliver electrical or chemical stimuli to a cell and record the electrical activity more...

"The Catseye is what great design is all about. Simple, functional, and beautiful" James May, presenter of British TV show Top Gear One night in 1933 when the road mender Percy Shaw (1890-1976) was driving home in Yorkshire, he saw the light of his car headlamps reflected in the eyes of a cat beside the road. This gave Shaw the inspiration that by replicating this effect he could produce a practical way of helping drivers navigate poorly lit roads. Shaw's challenge was to create a device bright enough to illuminate roads at night, robust enough to cope with cars constantly driving across it, and that also required minimum maintenance. Shaw came up with a small-device that could be inserted into the road as -a marker. It consisted of four glass beads placed in two pairs facing in opposite directions, embedded in a flexible rubber dome. When vehicles drove over the more...

Sir William Hamilton (1899-1978) already had some experience of working with water-based mechanics when he invented the jet boat. In 1954, he had built a jet pump, the first of its kind. The pump was essentially a system for water propulsion. It used a propeller to create a centrifugal force that caused a forward thrust action underwater, drawing water through and back inside the pump. The jet boat works in a similar way to the jet pump. Simply put, a traditional screw propeller accelerates a large volume of water by a small amount and, in agreement with Newton's Third Law of Physics—for every action there is an equal and opposite reaction—a large amount of thrust is created. This thrust is used to drive the boat and allows it to move speedily through the currents. Hamilton lived and worked in New Zealand. There his boat was able to power quickly through more...

In 1954 in Corpus Christi, Texas, Horton Glass Company employees, Dee Horton and Lew Hewitt, had just finished replacing yet another customer's wind- damaged glass door. Powerful, gusting South Texas winds wreaked havoc with traditional glass, push-pull doors, and ensured a steady demand for such repairs. Worse, the unpredictable winds could cause a door to blow open and shut in someone's face just as they were trying to walk through it. So the duo decided to invent a better door system. Initially, the system used a simple, electrically activated sliding door that opened only when a mat actuator in front of the door was stepped upon. Not only did this solve the problem of wind-blown accidents, it also enabled visitors or customers to leave, and delivery persons to enter a shop or business with their hands full. Having installed a test unit, for free, at the city's utilities department, sales more...

At the end of the eighteenth century, the Italian physicist Alessandro Volta invented the battery. By placing a pair of electrodes—one of zinc, the other of copper—in a solution that conducts electricity (sulfuric acid), he developed the principle that is still in use in today's dry-cell batteries. More than half a century later there had been many new versions of the battery, but there were still problems with the original Voltaic design. The solution that conducts the electricity, usually some kind of acid, was too dangerous to touch and could spill out if the battery was tipped over. Nor were the electrodes very steady and were in danger of falling out if the battery was shaken too much. Furthermore, the batteries themselves were far too heavy to use around the house. It was not until about 1866 that the French engineer Georges Ledanche (1839-1882) resolved these problems. Filling a porous more...

"Herminie had a simply ingenious idea. For women's corn fort she had cut in two the traditional corset." Cadolle website Before bras came along, corsets were the garment of choice for women to provide support and create a shapely silhouette of their figures. However, the whalebone reinforcement in corsets made them an uncomfortable and restricting item to wear. When Frenchwoman Herminie Cadolle (1845-1926) cut the corset in half in 1889, she created the very first bra. In the late nineteenth century, Cadolle moved to Buenos Aires in Argentina, where she opened a lingerie shop. There she had the idea of separating the corset into two parts. She unveiled her new design, which used shoulder straps for support and was called the corselet gorge, at the Great Universal Exhibition of 1889 in Paris. (Another feat of engineering—the Eiffel Tower—was also constructed for this event.) Cadolle's designs were among the first to more...