1st Class

"Beer is proof that God loves us and wants us to be happy.” Attributed to Benjamin Franklin When William Painter (1838-1906) left his home in Ireland in search of better opportunities in the United States, he could not have imagined that it would be a small, simple, and seemingly insignificant invention that would make him a very wealthy man and revolutionize the bottling industry. With hundreds upon hundreds of patents received for bottle-sealing devices, the trade press wrote that it would be difficult to come up with a novel idea. Painter took up the challenge, believing that "the only way to do a thing is to do it," and do it he did, filing a patent for the "Crown Cork" in 1891. The cap was metal with twenty-four teeth that gripped a flange around the neck of the bottle. It had a cork stopper on the inside to prevent the more...

"Knowledge belongs to humanity, and is the torch which illuminates the world" Louis Pasteur, scientist Before the invention of the torch or flashlight, it was impossible for children to experience the guilty pleasure of staying up late at night reading a book under the covers. It began life as the idea of Joshua Lionel Cowen, who wanted to make flowerpots light up as a decorative gimmick. He sold his company (and his idea) to Conrad Hubert (1856-1928), a manufacturer of Christmas lights and other electric novelties. Hubert decided to reinvent Cowen's light without the flowerpot. One of his shop workers, British inventor David Misell came up with a basic tube made from paper and other fibers, complete with a bulb and reflector in 1898. In an astute marketing move, New York's policemen were given the flashlights to try out, and soon everyone wanted one. Hubert's company became Eveready and its more...

"When we exhale, a large portion of the oxygen we inhaled, around 80 percent, is exhaled..." Adam Altman, Long Island Divers Association Scuba diving usually involves filling a tank with air, strapping it to your back, and breathing from it underwater. This simple system is called open circuit scuba (or self-contained underwater-breathing apparatus). Before this method of scuba diving caught on, however, people were using rebreathers. In 1878, Henry Fleuss built a diving system that allowed the user to breathe the same air over and over again. Using a rubber mask, a breathing bag, a copper tank, and a bit of string, he constructed the first scuba rebreather. A rebreather works by removing carbon dioxide from the diver's exhaled gas and recycling its usable components. The contraption uses an expandable breathing bag to hold the exhaled gas and a system of valves to keep the gas flowing in only one more...

"My father hated radio; he couldn't wait for television to be invented so he could hate that too." Peter De Vries, writer Selenium has a lower electrical resistance when it is soaked in bright light than it does when it is in darkness. This means that by altering the light shone onto a selenium cell, the amount of electricity that can pass through it can be changed. This, combined with the knowledge that all we see is made up of different shades of light and dark, allowed German engineer Paul Nipkow (1860-1940) to come up with a way to convert pictures into electrical signals. Nipkow's system worked by using a rotating disk that has a spiraled series of holes punched in it. When the disk turns, the moving holes break up the image into a series of varying light signals. When light passes through the holes onto the selenium cells, more...

"The truth is, a halftone is nothing more than a kind of magic trick" Bill Stephens, printer The popularity of photography soared during the 1800s and with that grew a desire to print photographs in books and newspapers. However, the printing press was not capable of producing the continuous tone images, with infinite shades of gray, of photographs. It was not until 1881 that American Frederic Ives (1856-1937) developed the first successful halftone process. Halftone printing involves converting continuous tone images to images made of dots of various sizes. The key to this system is that it exploits the limitations of the human eye. With the right resolution, the individual dots cannot be seen, resulting in the illusion of shades of gray, with larger dots appearing as darker shades. The first step is to produce a negative using a process camera. The process camera has a screen between the lens more...

A cyclone is a violent storm. It never comes alone. Heavy showers of rain, thunder and lightning are its companions. When a cyclone blows, it moves round and round in the form of small circles. It always changes its course when it blows. It does not move in the same direction like an ordinary storm. It occurs mostly in warm parts of the world. India is in this region of the world. Hence cyclones often blow over her. There are no cyclones in cold in cold countries.  There are some sings of the blowing of a cyclone. The weather becomes hot. There is not a breath of wind. Patches of dark cloud gradually spread in the sky. At last, the sky becomes dark. A storm sets in. The wind then begins to blow violently. From these we can understand that a cyclone will begin. Then it rains very heavily. Rashes more...

"The Iron Age itself came very early to Africa, probably around the sixth century B.C.E...." Richard Hooker, historian Steel was first produced in carbon furnaces in sub- Saharan East Africa, around 1500 B.C.E. Steel is an alloy of iron and 0.2-2.4 percent carbon. It can also contain trace elements such as vanadium, manganese, or tungsten. The carbon acts as a hardening agent and prevents the lattices of iron crystals from sliding past each other. The more carbon present in steel, the harder it is, but this is at the expense of increased brittleness. By controlling the exact ratio of iron to carbon and other elements, the properties of the steel can be tuned to those needed for a specific function. Damascan steel (also known as Wootz steel) was famed for its strength and ability to keep an edge. It actually originated from India around 300 b.c.e. before being widely exported; more...

“... the flash of a neon light that split the night/And touched the sound of silence." Paul Simon, "The Sound of Silence" Following the invention of the electric lightbulb by Edison and Swan in 1878, the race was on to improve its design and performance. French chemical engineer, Georges Claude (1870-1960) was working on an invention to extract oxygen from air, for use in hospitals and welding, and his experiments resulted in his discovery of the noble .gases—helium, argon, krypton, xenon, radon, and neon—so called because they do not react with other elements. Aware of the race for the perfect lightbulb, Claude experimented by passing an electric current through tubes containing different noble gases at low pressure. In 1902 he discovered that neon gas, with only a small current, produced an intense orange glow. He was unimpressed by the amount of light it produced, but Jacques Fonseque, an advertising agent, more...

Danish engineer Valdemar Poulsen (1869-1942) developed the first magnetic recording system. It was the direct antecedent of analog tape recording, the medium for which most audio was captured throughout the twentieth century. The operating principles differed little from later analog recording systems. A motorized assembly pulled a spool of hair-thin wire at a constant speed across a magnetic recording head. The sound intended for capture was converted to electrical pulses that were then fed through a record head that imposed a pattern of magnetization onto the wire analogous to the original signal. The spool was then rewound, and the wire passed across a playback head that detected changes in the magnetic field stored on the wire; these were converted back to a continuous electrical signal that could then be heard. Poulsen patented his Telegraphone in 1898. Two years later he took it to the World Exposition in Paris, where he more...

Wallace Carothers (1896-1937) was an excellent chemist and, as an undergraduate, was made head of the chemistry department at Tarkio College, Missouri. After becoming a professor at Harvard, he was lured into industry by chemical company DuPont, which had opened a science laboratory to develop new products. In 1928 he headed up a team looking into artificial materials. Carothers was interested in the hydrocarbon acetylene and its family of chemicals. After having developed the first synthetic rubber polymer—mass produced by DuPont as neoprene in 1931—he looked into creating a man-made synthetic fiber that could replace silk. Japan was the United States's main source of silk, but trade relations were breaking down as the political situation between the two countries worsened. Silk was becoming harder to source and very expensive. In 1935, Carothers made significant steps toward a silklike fiber by developing a chemical reaction between chemical units called monomers. The more...