BAKELITE
Bakelite (also called catalin) is a plastic, a dense synthetic polymer (a phenolic resin) that was used to make jewelry, game pieces, engine parts, radio boxes, switches, and many, many other objects. Bakelite was the first industrial thermoset plastic (a material that does not change its shape after being mixed and heated). Bakelite plastic is made from carbolic acid (phenol) and formaldehyde, which are mixed, heated, and then either molded or extruded into the desired shape.
BAROMETER
A barometer is a device that measures air (barometric) pressure. It measures the weight of the column of air that extends from the instrument to the top of the atmosphere. There are two types of barometers commonly used today, mercury and aneroid (meaning "fluidless"). Earlier water barometers (also known as "storm glasses") date from the 17th century. The mercury barometer was invented by the Italian physicist Evangelista Torricelli (1608 - 1647), a pupil of Galileo, in 1643. Torricelli inverted a glass tube filled with mercury into another container of mercury; the mercury in the tube "weighs" the air in the atmosphere above the tube. The aneroid barometer (using a spring balance instead of a liquid) was invented by the French scientist Lucien Vidie in 1843.
BATTERY
A battery is a device that converts chemical energy into electrical energy. Each battery has two electrodes, an anode (the positive end) and a cathode (the negative end). An electrical circuit runs between these two electrodes, going through a chemical called an electrolyte (which can be either liquid or solid). This unit consisting of two electrodes is called a cell (often called a voltaic cell or pile). Batteries are used to power many devices and make the spark that starts a gasoline engine.
Alessandro Volta was an Italian physicist invented the first chemical battery in 1800.
BUNSEN BURNER
The laboratory Bunsen burner was invented by Robert Wilhelm Bunsen in 1855. Bunsen (1811-1899) was a German chemist and teacher. He invented the Bunsen burner for his research in isolating chemical substances - it has a high-intensity, non-luminous flame that does not interfere with the colored flame emitted by chemicals being tested.
CASSEGRAIN TELESCOPE
A Cassegrain telescope is a wide-angle reflecting telescope with a concave mirror that receives light and focuses an image. A second mirror reflects the light through a gap in the primary mirror, allowing the eyepiece or camera to be mounted at the back end of the tube. The Cassegrain reflecting telescope was developed in 1672 by the French sculptor Sieur Guillaume Cassegrain. A correcting plate (a lens) was added in 1930 by the Estonian astronomer and lens-maker Bernard Schmidt (1879-1935), creating the Schmidt-Cassegrain telescope which minimized the spherical aberration of the Cassegrain telescope.
CELLOPHANE
Cellophane is a thin, transparent, waterproof, protective film that is used in many types of packaging. It was invented in 1908 by Jacques Edwin Brandenberger, a Swiss chemist. He had originally intended cellophane to be bonded onto fabric to make a waterproof textile, but the new cloth was brittle and not useful. Cellophane proved very useful all alone as a packaging material. Chemists at the Dupont company (who later bought the rights to cellophane) made cellophane waterproof in 1927.
CELSIUS, ANDERS
Anders Celsius (1701-1744) was a Swedish professor of astronomy who devised the Celsius thermometer. He also ventured to the far north of Sweden with an expedition in order to measure the length of a degree along a meridian, close to the pole, later comparing it with similar measurements made in the Southern Hemisphere. This confirmed that that the shape of the earth is an ellipsoid which is flattened at the poles. He also cataloged 300 stars. With his assistant Olof Hiorter, Celsius discovered the magnetic basis for auroras.
COMPOUND MICROSCOPE
Zacharias Janssen was a Dutch lens-maker who invented the first compound microscope in 1595 (a compound microscope is one which has more than one lens). His microscope consisted of two tudes that slid within one another, and had a lens at each end. The microscope was focused by sliding the tubes. The lens in the eyepiece was bi-convex (bulging outwards on both sides), and the lens of the far end (the objective lens) was plano-convex (flat on one side and bulging outwards on the other side). This advanced microscope had a 3 to 9 times power of magnification. Zacharias Janssen's father Hans may have helped him build the microscope.
FRANKLIN, BENJAMIN
Benjamin Franklin (January 17, 1706-April 17, 1790) was an American statesman, writer, printer, and inventor. Franklin experimented extensively with electricity. In 1752, his experiments with a kite in a thunderstorm (never do this, many people have died trying it!) led to the development of the lightning rod. Franklin started the first circulating library in the colonies in 1731. He also invented bifocal glasses and the Franklin stove. The idea of daylight savings time was first proposed by Benjamin Franklin in 1784.
GALILEI, GALILEO
Galileo Galilei (1564-1642) was an Italian mathematician, astronomer, and physicist. Galileo found that the speed at which bodies fall does not depend on their weight and did extensive experimentation with pendulums.
In 1593 Galileo invented the thermometer.
GEIGER COUNTER
The Geiger counter (sometimes called the Geiger-Muller counter) is a device that detects ionizing radioactivity (including gamma rays and X-rays) - it counts the radioactive particle that pass through the device. The German nuclear physicist Hans Wilhelm Geiger (Sept. 30, 1882- Sept. 24, 1945) developed the device from 1908-12. At that time, Geiger was an assistant to the British physicist Ernest Rutherford (1871-1937). [Geiger's work helped Rutherford discover that radioactive elements can transform into other elements and that atoms have a nucleus]. In 1928, the Geiger counter was improved by the German physicist E. Walther Muller.
GYROSCOPE
A gyroscope is essentially a spinning wheel set in a movable frame. When the wheel spins, it retains its spatial orientation, and it resists external forces applied to it. Gyroscopes are used in navigation instruments (for ships, planes, and rockets). Jean Bernard Léon Foucault (1819-1868), a French physicist, invented the gyroscope in 1852.
KELVIN
Lord Kelvin (William Thomson, 1824 - 1907) designed the Kelvin scale, in which 0 K is defined as absolute zero and the size of one degree is the same as the size of one degree Celsius. Water freezes at 273.16 K; water boils at 373.16 K.
NOBEL, ALFRED
Alfred Bernhard Nobel (1833-1896) was a Swedish inventor and industrialist. Nobel invented many powerful and relatively safe explosives and explosive devices, including the "Nobel patent detonator" (it detonated nitroglycerin using a strong electrical shock instead of heat, 1863), dynamite (1867), blasting gelatin (guncotton plus nitroglycerin, 1875), and almost smokeless blasting powder (1887). Nobel also made inventions in the fields of electrochemistry, optics, biology, and physiology. Nobel left much of his fortune to award prizes (the Nobel prizes) each year to people who made advancements in Physics, Chemistry, Physiology/Medicine, Literature, and Peace.
PASTEUR, LOUIS
Louis Pasteur (1822-1895) was a French chemist and inventor. Pasteur studied the process of fermentation, and postulated that fermentation was produced by microscopic organisms (other than yeast), which Pasteur called germs. He hypothesized that these germs might be responsible for some diseases. Pasteur disproved the notion of "spontaneous generation " which stated that organisms could spring from nothing; Pasteur showed that organisms came form other, pre-existing organisms. Applying his theories to foods and drinks, Pasteur invented a heating process (now called pasteurization) which sterilizes food, killing micro-organisms that contaminate it.
RADIO TELESCOPE
A radio telescope is a metal dish that gathers radio waves from space. Radio astronomy involves exploring space by examining radio waves from outer space. Radio astronomy was pioneered by Karl G. Jansky, who in 1932 first detected radio waves from a cosmic source - in the central region of the Milky Way Galaxy. Gote Reber (a ham radio operator) made the first true radio telescope (using a 32-foot diameter parabolic dish to focus the radio waves) after reading of Jansky's discoveries. One example of a radio telescope is the Very Large Array (VLA) in New Mexico.
ROENTGEN, WILHELM VON
X-rays were discovered in 1895 by Wilhelm Konrad von Roentgen (1845-1923). Roentgen was a German physicist who described this new form of radiation that allowed him to photograph objects that were hidden behind opaque shields. He even photographed part of his own skeleton. X-rays were soon used as an important diagnostic tool in medicine. Roentgen called these waves "X-radiation" because so little was known about them.
STEAM ENGINE
The steam engine was invented by Heron, an ancient Greek geometer and engineer from Alexandria. Heron lived during the first century AD and is sometimes called Hero. Heron made the steam engine as a toy, and called his device "aeolipile," which means "wind ball" in Greek. The steam was supplied by a sealed pot filled with water and placed over a fire. Two tubes came up from the pot, letting the steam flow into a spherical ball of metal. The metallic sphere had two curved outlet tubes, which vented steam. As the steam went through the series of tubes, the metal sphere rotated. The aeolipile is the first known device to transform steam power into rotary motion. The Greeks never used this remarkable device for anything but a novelty. A steam engine designed for work wasn't built until 1698 (built by the British inventor, Thomas Savery). Watt later improved the steam engine.
TESLA, NIKOLA
Nikola Tesla (1856-1943) was a Serbian-American inventor who developed the radio, fluorescent lights, the Tesla coil (an air-core transformer that generates a huge voltage from high-frequency alternating current), remote-control devices, and many other inventions; Tesla held 111 patents. Tesla developed and promoted the uses of alternating current (as opposed to direct current, which was promoted fiercely by Thomas Edison and General Electric). Tesla briefly worked with Thomas Edison. The unit of magnetic induction is named for Tesla; a tesla (abbreviated T) is equal to one weber per square meter.
VON ROENTGEN, WILHELM
X-rays were discovered in 1895 by Wilhelm Konrad von Roentgen (1845-1923). Roentgen was a German physicist who described this new form of radiation that allowed him to photograph objects that were hidden behind opaque shields. He even photographed part of his own skeleton. X-rays were soon used as an important diagnostic tool in medicine. Roentgen called these waves "X-radiation" because so little was known about them.
WATT, JAMES
James Watt (1736-1819) was a Scottish inventor and engineer. In 1765, Watt revolutionized the steam engine, redesigning it so that it was much more efficient and four times as powerful as the old Newcomen steam engines. Watt's engines did not waste steam (heat), and had a separate condenser. Watt partnered with the businessman and factory owner Matthew Boulton in 1772, helping to promote Watt's ideas commercially. Watt also invented a method for converting the up-and-down piston movement into rotary motion (the "sun-and-planet" gear), allowing a greater number of applications for the engine. Watt produced this rotary-motion steam engine in 1781; it was used for many applications, including draining mines, powering looms in textile factories, powering bellows, paper mills, etc. It helped power the Industrial Revolution. Watt coined the term "horsepower," which he used to convey the power of his engines; Watt calculated how many horses it would take to do the work of each engine. One horsepower equals 33,000 foot-pounds of work per minute; it is the power required to lift a total of 33,000 pounds one foot in one minute. Parliament granted Watt a patent on his steam engine in 1755, making Watt a very wealthy man. In 1882 (long after Watt's death), the British Association named the unit of electrical power the "watt."
Last But Not Least
The One and Only
EDISON, THOMAS ALVA
Thomas Alva Edison (1847-1931) was an American inventor (also known as the Wizard of Menlo Park) whose many inventions revolutionized the world. His work includes improving the incandescent electric light bulb and inventing the phonograph, the phonograph record, the carbon telephone transmitter, and the motion-picture projector.
Edison's first job was as a telegraph operator, and in the course of his duties, he redesigned the stock-ticker machine. The Edison Universal Stock Printer gave him the capital ($40,000) to set up a laboratory in Menlo Park, New Jersey, to invent full-time (with many employees).
Edison experimented with thousands of different light bulb filaments to find just the right materials to glow well, be long-lasting, and be inexpensive. In 1879, Edison discovered that a carbon filament in an oxygen-free bulb glowed but did not burn up for quite a while. This incandescent bulb revolutionized the world.
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