Science Projects And Inventions

Telegraphing is a way of sending messages using wires and an electric current. At one end, the sender naps out a word with a switch. Each tap completes the circuit and allows electricity to flow. The electricity flows down wires to the receiver, where it powers an indicator dial or pointer, enabling the operator to observe the message coming in. Early forms of the telegraph were based on electrolysis, in which electricity passes through a liquid to produce a visual effect. Samuel Thomas von Sommering'S early electrolysis telegraph consisted of thirty wires immersed in acidic water, one for each letter of the German alphabet. As the letters were tapped and the circuit completed, an electrochemical reaction produced a flow of hydrogen bubbles. The message was easily deciphered by watching which wire produced the bubbles. Baron Pavel Schilling (c. 1780-1836) decided to collaborate with von Sommering to invent a more practical more...

In 1835, shortly after the American Joseph Henry (1797-1878) became a professor at Princeton University, he passed crude on/off messages from his laboratory to his nearby home on campus using an electromagnetic relay and a current-carrying wire. In the early relays, switching an electrical current on or off magnetized the relay's electromagnet core, and this magnetic field attracted a pivoting iron armature, which itself operated a set of contacts that made or broke an electrical circuit. One of the advantages of such relays was that the current through the electromagnet could be very small, and the switched-circuit current could be much larger. Relays formed the basis of the telegraph system and were at the heart of telephone exchanges. In modern industry, electromagnetic relays are used to control electric motors and are a vital component of automated systems of machine manufacture. Great advances have been made in relay design, mainly to more...

"We waste our lights in vain, like lamps by day..." William Shakespeare, Romeo and Juliet George Carwardine's (1887-1948) company was a car manufacturing factory and it was there that he came up with the idea of arranging springs on a metal arm that could be adjusted in orientation and yet stay in place when released. The design mimicked the. movement of the human arm and was inspired by the constant tension principle. He patented the design in 1931, but it was not until the year after that the idea came to him to use it to angle temporarily the direction of a lamp. To the moveable sprung arm, he attached a heavy base and a directional lamp, which allowed the lamp to be moved to face any direction but remain rigid in position. Carwardine found the lamps useful in his factory for illuminating the assembly process, but he soon realized more...

Chlorofluorocarbons (CFCs) were for decades commonly used in the cooling systems of refrigerators and in aerosol cans. However, when these usually inert compounds get zapped by radiation in the upper atmosphere, they are energized and produce chlorine radicals that react with ozone. This has led to a significant depletion in the ozone layer, notably at the North and South Poles. The world was on the brink of losing its natural protection from harmful ultraviolet (UV) rays, mostly thanks to a household appliance used worldwide. Ironically, CFCs started out as savior compounds, replacing nasty substances such as ammonia and sulfur dioxide in refrigeration equipment. Faulty units would cause unpleasant illnesses and even deaths. The American Thomas Midgley (1889-1944) first proposed CFCs as refrigerants in 1928, demonstrating their suitability with theatrical flourish—he proved their lack of reactivity and toxicity by inhaling the gas and then exhaling onto a lit candle. Developed with more...

The backhoe loader, or JCB®, was invented by Joseph Cyril Bamford (1916-2001) of Staffordshire, England. In 1945, using only scrap metal, war surplus Jeep axles, and a cheap welding kit, he produced an hydraulically operated tipping trailer that he later sold for £45 ($180 at the time). With the dump truck-like tipping trailer created, Bamford's business grew steadily as he designed and built new machines using hydraulic power. When the backhoe loader was created in 1953, the JCB®  logo was used for the first time, based on its inventor's initials. Typical backhoe loaders are made up of three components: a tractor, a loader, and a backhoe. The tractor enables the backhoe loader to traverse difficult terrain of all sorts. At the front of the tractor, the loader can scoop, smooth, and push great quantities of material. Meanwhile, the back of the tractor sports a backhoe, which is a large maneuverable more...

The Internet? Television? The internal combustion engine? All of these things are important, but they pale in significance next to arguably the most important invention of all time—the toilet. Archeological research indicates that toilets flushed by water have existed since about 2500 B.C.E. Inhabitants of the Indus Valley developed a sophisticated system of toilets and accompanying plumbing; each house had a toilet with a seat, the waste being borne away by water in a sewer system covered with dry-clay bricks. This system was used in India for most of the existence of the Indus Valley Civilization, which ran from about 3000 to 1700 B.C.E. Ancient Egypt also developed a similar system that removed waste through the use of running water. The ancient Romans were so fastidious that .they constructed a toilet for use when they were traveling. Their sewerage systems were sophisticate and public toilets were common. After some lamentably more...

In 1791 the English inventor John Barber (1734-1801) patented "an Engine for using Inflammable Air for the Purpose of procuring Motion." We now know his invention as the gas turbine, a mechanism that was simultaneously 150 years before its time and based on an idea more than 1,700 years old. A turbine is a machine that turns the energy of moving gas or liquid into rotational energy During the first century, the Greek inventor Hero of Alexandria developed the first steam turbine. His device drove steam from boiling water through curved nozzles to rotate a cylinder. John Barber's engine, while based on similar principles, included features not present in its ancient predecessor. A gas turbine engine such as Barber's has three main components: a compressor to increase the pressure of the air, a combustion chamber in which the air is combined with fuel to produce an explosion, and a turbine more...

The modern era of photography began in 1861 with the invention and patenting of the world's first single- lens reflex (SLR) camera by photography expert Thomas Sutton (1819-1875). His prototype led to the creation of the first batch of SLR cameras in 1884, with a design that f5 still in use today. Sutton also assisted James Clerk Maxwell in his successful demonstration of color photography in 1861. In non-SLR cameras, light enters the viewfinder at a slightly different angle to that at which it enters the lens, so the resulting photo can appear different to the intended composition. In SLR cameras, a mirror is positioned in front of the lens and directs light up into a pentaprism. The light bounces between its edges until it enters the viewfinder with correct orientation, as if the viewer is looking directly through the camera lens. When a photograph is taken, the mirror moves more...

From the Victorian era, right up until the 1960s, mothers struggled with huge and heavy baby carriages. These days, however, a stroller is the item at the top of every new parent's baby list. Not only do parents appreciate the practicalities of having a stroller that they can fold up and carry under one arm, they also want to distance themselves from the unstylish and cumbersome older styles of baby buggy. Unexpectedly; the inventor of the collapsible stroller was Owen Maclaren (1907-1978), a retired test pilot who had previously designed landing gear and protective seals for Spitfire aircraft. His departure into strollers may seem odd, but building a practical stroller required knowledge of strong, lightweight structures, and Maclaren's aeronautics experience had given him exactly that. At around 6 ½ pounds (3 kg), Maclaren's first model cost about $10 (£7) and weighed less than the child it was intended to seat—his more...

Early telegraphs led to improved communication but were limited by a lack of readily available power. In 1839 Welsh scientist Sir William Grove (1811-1896) tried to tackle this problem by designing a device that could generate a strong flow of electricity. Grove's electrochemical device harnessed the energy released by a chemical reaction to generate electricity. Grove's first attempt consisted of zinc In dilute sulfuric acid and platinum in concentrated nitric acid, separated by a porous pot. The "Grove Cell" was the favored power source in the mid-nineteenth century because it produced a strong current. However, as telegraph traffic increased, it soon became apparent that the cells were releasing poisonous, nitric oxide gas. Large telegraph offices were filled with smoke from rows of hissing Grove cells. Grove's second electrochemical cell, the "Gas Voltaic Battery," provided the basis for the modern fuel cell. His idea was based on the fact that sending more...