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Wright Brothers Fly First Motorized Plane

Orville and Wilbur Wright were inspired by Otto Lilienthal, a German glider pioneer. Though he crashed to his death in 1896, the Wrights were obsessed by the technical problems involved in flight. They approached the issue methodically, working out ways to control a glider's tendency to pitch up and down, roll side to side, or yaw left and right. By the third glider they built, they had solved most of these problems of steering and stability.

To make a self-powered airplane, they needed to develop a very light gasoline engine and an appropriate propeller. By December 1903, their first airplane (Flyer /, later renamed Kitty Hawk) was ready to test. It had a 12.3 meter wingspan; was 6.4 meters long, and weighed about 274 kilos without the pilot. It was powered by the Wrights' home-made 12 horsepower gasoline engine. The Wrights returned to the site at Kill Devil Hill near Kitty Hawk, North Carolina, where they had tested their gliders. Their selection of this spot was based on national weather records which showed it to have consistently favorable conditions.

The first day's attempt was unsuccessful, but in a few days, Orville flew the plane 37 meters, which took 12 seconds. They made several more flights that day, the longest being 260 meters in 59 seconds. The Wrights press release sent out the following month was largely ignored. Many people just didn't believe it, though there were five witnesses to their first flights.

Orville later wrote of that first motorized flight:"With all the knowledge and skill acquired in thousands of flights in the last ten years, I would hardly think today of making my first flight on a strange machine in a 27 mile wind, even if I knew that the machine had already been flown and was safe. After these years of experience I look with amazement upon our audacity in attempting flights with a new and untried machine under such circumstances. Yet faith in our calculations and the design of the first machine, based upon our tables of air pressures, secured by months of careful laboratory work, and confidence in our system of control developed by three years of actual experiences in balancing gliders in the air had convinced us that the machine was capable of lifting and maintaining itself in the air, and that, with a little practice, it could be safely flown.(1965)

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Henry Ford and the Automobile Revolution.

Why the Model-T dominated US car sales.

In 1896 an American named Henry Ford exhibited a 4-cycle, 2-cylinder, 4- wheeled cart in Detroit's Bagley Avenue. After his first demonstration, he began to build "racing cars" for publicity. Then in 1903, Ford Motor Company sold its first car: a 2- cylinder car for $2,500. Nonetheless, Ford felt that the price was too much for a consumer vehicle. 'The market for a low priced car," Ford once said, "is unlimited." A few later in 1908, Ford Motor Company unveiled its $850 Model T, which included a folding windshield, a removable top, horn, and gas lamps. The 22.5 horsepower engine had a top speed of 35 miles per hour. When asked about the limited color choice for the Model T, Ford jokingly replied, "You can have any color - so long as it’s black".



By the time production of the "flivver" or "tin Lizzie," as the Model T was called, ended in 1927 Ford had sold over 15 million of them. Prices of the car steadily dropped as it became more popular; in 1923 it reached a low of $265. Many companies sprang up in wake of the Model T’s popularity. To help solve the problem of the engine "kicking" when it was cranked, a Wisconsin based company sold an automatic spark retarder. Other companies tried to improve the simple design ofthe car by selling "1-man tops," rear-view mirrors, electric lamps, and various other accessories.

The Model Twos introduced on October 1, 1908 and so technically may be considered a 1909 model in line with the industry practice of dating cars by model year. Over the next 18 years, the Model T would dominate US car sales. In 1911-

1918 and 1921. Ford earned more than all other automakers combined.(1415)

Radio

Do you have a favorite radio station? What do you like about it? Have you ever wondered how your radio is able to produce the sounds and the music that you like to hear?

Radio programs are sent by a machine called a transmitter to your radio which is called a receiver. The programs don't travel through wires like telephone messages do. They are sent through the air over long distances by electromagnetic waves. These waves are called radio waves and were discovered by a German scientist named Heinrich Hertz. He discovered that these waves could carry sound signals. He also discovered that radio waves have different lengths.

Guglielmo Marconi, an Italian, invented a microphone that changed sound waves into electronic signals, and then he developed a receiver that turned them back into sound again. He also found a way to keep waves of the same length together and keep those of different wave lengths separate. On his equipment, a radio wave looked like a letter "s" lying on its side. Short waves curved up and down more times each second than longer ones, so he divided all the waves by how many times they curved each second or by how frequently they curved. He called each group a frequency. The numbers on your radio dial are different frequencies. Different stations can broadcast their programs at the same time using different frequencies.

Later, scientists found that by using only the top half of a radio wave they could reduce static and other noise that interfered with clear sound. This kind of radio transmission is called FM broadcasting because the frequency has been modulated or changed.(1345)

Television is Developed.

John Logie Baird (1888-1946) applied for a patent for a mechanical television in 1923. He ran successful experiments in transmitting images in 1926, and in 1930 he worked with the British Broadcasting Corporation (BBC) to begin mechanical television broadcasting. He also tried, rather unsuccessfully, to mass-market his television transmitter.

In 1923 Vladimir Zworykin (1889-1982) also applied for a patent. He was for a television camera that converted optical images into electrical pulses. On November 18, 1929, at a convention of radio engineers, Zworykin demonstrated a television receiver containing his “kinescope”, a cathoderay tube. That same year Zworykin joined the Radio Corporation of America (RCA) in Camden, New Jersey. As the director of their Electronic Research Laboratory, he was able to concentrate on making critical improvements to his system. Zworykin’s “storage principle” is the basis of modem TV.

Meanwhile, in Japan, Kenjiro Takayanagi was developing electronic television, too. He was ahead of Zworykin, but better publicity gave Zworykin the nickname “father of television.” Takayanagi transmitted an image electronically in 1926, with a 40-line resolution and film running at 14 frames per second.

In 1932 the BBC ventured the first regularly broadcast programs using Baird’s mechanical equipment, though it had been broadcasting special events and other sporadic transmissions since 1927. The first special-purpose television station was built in Germany in 1935 in preparation for the Berlin Olympic Games the following year. That Olympic year, NBC experimented with electronic broadcast from the top of the Empire State Building. The first live journalistic event covered by television was the 1937 coronation of Britain’s King George That year, the BBC began the first regular, high-quality broadcasting service using an electronic system.(1622)

Vacuum Cleaner

The idea of a vacuum cleaner originates from the 19th century.

The first vacuum cleaners had to be operated manually. Two persons were needed for this: one to operate the bellows and the other to move the mouthpiece over the floor. The dust was blown into the air. Only in 1901 Hubert Booth changed the idea into something more useful. Until then the vacuum cleaners blew the dust away, but Booth came up with the idea of sucking away dust, instead of blowing. Furthermore, Booth equipped his cleaner with a filter, which kept the dust in the machine. All modem vacuum cleaners are based on Booth's principle. In spite of the improvements made by Booth, the older vacuum cleaners were not very practical: they were hand-operated and very-big and heavy. Some cleaners were left outside the house, and only the hose was led into the rooms through a window or door. Best known for the vacuum cleaner that bears his name, Jim Kirby’s life goal was to reduce or eliminate drudgery wherever it ex­isted. After watching his mother's cleaning effort result in the dust settling back onto everything in the house, he developed his concept of a vacuum cleaner. His first cleaner, invented in 1906. used water for dirt separation. In 1907, displeased with the unpleasant task of disposing of dirty water, he went back to work and designed a system that used centrifugal action and cloth to filter the dirt. After World War I, Mr. Kirby agreed to design vacuum cleaners exclusively for George Scott and Carl Fetzer. Over the ensuing years, he developed numerous innovative cleaner designs. The Ezee vacuum cleaner (pictured at left), nicknamed the "Grasshopper" was one of Jim Kirby's early designs. Developed in 1912, it was a non-electric cleaner designed to serve households in rural communities without access to electrical power. Later, the non-electric Vacuette model, manufactured by Scott and Fetzer, became the forerunner of today's multi-attachment models. In 1935, Scott and Fetzer introduced the model C, the first of a long line of products to carry Kirby's name. Jim Kirby continued to work on new ideas for the company into the 1960 s.(1792)

Clothes Washer

And you wonder why it is called the Stone Age. In the good old days, clothes were washed in a stream, by bounding the garments with rocks, stones and heavy sticks. Forget about soap water was the sole cleansing agent.

Fire added heat to the laundry mix, when clothes were washed in tubs with water heated over open fires and soap made at home from a combination of lye and ashes. Clothes were scrubbed on a corrugated board, wrung by hand, rinsed, then wrung again, and draped on lines or bushes to dry. Women's hands were freed by 1927, when wringer washers became standard, eliminating the washboard, open tubs and the boiler. A few "pumps" with the foot started the motor of the machine and kept it humming.

The first automatic washer - one that washed, rinsed and extracted water from clothes in one process - debuted at a county fair in Louisiana, in September of 1937. After World War II, the demand for washers was enormous. By 1953, automatic washers were outselling wringer washers ten to one.

Today, washers offer a variety of features including a selection of cycles for washing different types of garments and water temperature and level options.(970)

Regrigerator

The earliest method of refrigeration was the storage of food in caves and cold springs. This method of storing food in cold places slowly evolved, as people began keeping food in their cellars, in their outdoor window boxes, in the snow, or underwater in nearby lakes, streams or wells. The invention of the icebox led to more efficient refrigeration. Ice was delivered to houses by delivery men and was used in wooden iceboxes

that were lined in tin or zinc and insulated with sawdust or seaweed. The use of ice for refrigeration continued until World War I, when mechanical refrigeration came on the market. The first electric refrigerators with freezer compartments came on the market in the 1920s and 1930s. However, the mass production of refrigerators began after World War 11, when researchers had been able to successfully adapt large refrigeration systems for use in homes and shops. In the 1950s and 1960s, the invention of automatic defrost and automatic ice makers further improved the efficiency of refrigerators. Refrigerators also became available in a wide variety of size, color, and design.(940)

The Microwave Oven

 

Shortly after the end of World War II, Percy Spencer, already known as an electronics and war hero, was touring one of his laboratories at the Raytheon Company. He stopped momentarily in front of a magnetron, the power tube that drives a radar set. Feeling a sudden and strange sensation, Spencer noticed that the chocolate bar in his pocket had begun to melt. Spencer, who obtained 120 patents in his lifetime, knew how to apply his curiosity. So he did what any good inventor would he went for some popcorn. Spencer didn't feel like having a snack, he asked for unpopped popcorn. Holding the bag of corn next to the magnetron, Spencer watched as the kernels exploded into white morsels.

From this simple experiment, Spencer and Raytheon developed the microwave oven. The first microwave oven weighed a hefty 750 pounds and stood five feet, six inches. At first, it was used exclusively in restaurants, railroad cars and ocean liners - places where large quantities of food had to be cooked quickly. But culinary experts quickly noticed the oven's shortcomings. Meat refused to brown. French fries turned white

and limp. To make matters worse, Raytheon chairman Charles Adams cook quit because Adams demanded he prepare food with a microwave oven. In fact, it took decades after the invention of the microwave oven for it to be refined to a point where it would be useful to the average consumer. Today, Percy Spencer's radar boxes melt chocolate and popcorn in millions of homes around the world.(1261)


Date: 2015-01-29; view: 407


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