Miscelleneous

"An amazing invention—but who would ever want to use one?" Rutherford B. Hayes, U.S. president (1877-1881) In the 1870s Edinburgh-born Alexander Graham Bell (1847-1922) was working on a way to improve the telegraph. Although this was well established as a means of long-distance communication, the fact that only one message could be sent at any one time made it extremely limited. Bell's original idea was to develop a "harmonic telegram," using multiple pitches to transmit more than one message at the same time. While working on this, an idea came to him for a more elaborate system—one that could transmit not only the dots and dashes of Morse code, but actual speech. Several other teams were also pushing to transmit sounds via electricity, and there remains some controversy as to whether ideas were "borrowed" from other inventors, but it is undisputed that it was Bell who built the first working more...

The late nineteenth century was a time of tremendous scientific growth, which included the birth of radium therapy—that is, treating cancer with radiation. Rontgen discovered X-rays in 1895 and Becquerel followed soon afterward in 1896 with his discovery of radioactivity. It did not take long for the physicians of the day to put the newly discovered energy source to work, with the first published report of the use of a radioactive substance to treat a disease occurring before the turn of the century. The early use of radiation was almost laughably crude, with doctors simply exposing various neoplasms to a radiation source with no control over the amount of radiation an individual was exposed to or any sort of ability to focus the area of the exposure. Reports of cancers controlled or even cured by these new techniques were rampant, and radiation was felt to have great promise. Unfortunately, the more...

German engineer Nikolaus Otto (1832-1891) was responsible for one of the great developments in motorized vehicles with the invention of his four-stroke cycle internal combustion engine. After developing an interest in technology, he began designs for a four-stroke engine based on Lenoir's earlier design for a two-stroke cycle. In 1864 he set up N. A. Otto and Cie alongside Eugene Langer, creating the world's first engine manufacturers. In 1872, he employed Gottlieb Daimler and Wilhelm Maybach as technical director and chief designer, respectively. In 1876 the first practical four-stroke engine was constructed. The four strokes are an intake stroke, where the piston moves down to allow a fuel-air mixture into the combustion chamber; a compression stroke, where the piston moves back up to compress the gases; a combustion or power stroke, where a spark ignites the fuel and the piston is forced down again; and a final exhaust stroke, where more...

In 1906 the Amalgamated Radio Telegraph Company was founded as a merger between the UK De Forest Wireless Telegraph Syndicate and the fledgling operation run by Danish inventor Valdemar Poulsen (1869-1942). Before too long they had successfully established an experimental wireless telegraphy link between  Newcastle, England, and  Denmark. Unfortunately, the Amalgamated Radio Telegraph Company went bankrupt in 1907 before any commercial operation could be set up. The historic event had been made possible by Poulsen's invention of the arc transmitter in 1903. Pouslen was an electrical engineer and prolific inventor who, by 1898, had invented the first device to use magnetic sound recording—the "Telegraphone." Poulsen did not stop there. He became interested in the work of British inventor William Duddell who used a carbon arc lamp to make a resonant circuit that could "sing." Duddell's musical arc resonated at audible frequencies and he adapted this into a crude electronic musical more...

"Tape recording in your basement or bedroom used to be a freak thing. Now anybody can do it." Les Paul, musician At the end of the nineteenth century, Valdemar Poulsen developed the telegraphone as a means of recording sound on a magnetized wire. However, the sound quality of these machines was poor, and the wire itself was usually built into the machine, making it of little use for long-term audio storage. A breakthrough came in 1928 when German engineer Dr. Fritz Pfleumer (1881-1945) successfully fixed magnetic powder to a thin strip of paper. This was then able to record magnetic signals more effectively than magnetic wire. In 1930, the AEG company of Berlin began work on the magnetophone, an audio recorder that would make use of the Pfleumer principle. To develop the tape itself, it collaborated with another illustrious name in German electronics, BASF, which used its expertise in plastics more...

In 1902 American president Theodore Roosevelt went on a bear hunting expedition in Mississippi that led to the invention of perhaps the most iconic children's toy in history. Holt Collier, a former slave and prodigious huntsman, was charged with organizing the chase. In order to provide Roosevelt with a clear shot, Collier and his hounds tracked down a bear and drove it to the stand where the president was waiting. However, when Collier arrived with the bear, Roosevelt had left for lunch. In the ensuing confusion the bear attacked one of the hunting dogs. But unwilling to kill the beast he'd promised to the president, Collier simply knocked it out with his rifle and tied it to a tree. When Roosevelt returned a short while later he was impressed by Collier's feat, but refused to kill the defenseless bear. The episode gained widespread media attention, and in November 1902 the more...

"Engineering is the... art of applying science to the optimum conversion of natural resources." Professor Ralph J. Smith, Stanford University Die-casting is the name given to a process of producing identical and often complicated metal parts by forcing molten metal under high pressure into a reusable type of mold, which is known as a die. It is a four-step process. First the inside of the die is coated with a lubricant—used partly to help control the temperature of the mold, and partly to aid the removal of the cast when complete. Molten metal is then injected into the die under high pressure. Generally non ferrous metals are used in die-casting. Zinc is popular as it is easy to cast and has a low melting point, which increases the working lifespan of the die. Aluminum is also used as it is very lightweight. The metal is kept under pressure until the more...

The phonograph (gramophone) record was invented in 1887 by German-born, American inventor Emile Berliner (1851-1929). His flat, rotating disc involved the stylus moving horizontally across the record rather than vertically, as with the cylinders used previously. Berliner's recording stylus cut down on sound distortion and was easier to manufacture than the cumbersome wax cylinders. Early phonograph records were made from a mixture of hard rubber, cotton, and powdered slate, although shellac (a form of commercial resin) was later used after its introduction in 1896. Phonograph records were initially single sided but the double-sided disc became common after about 1923. They usually came in three standard sizes, 7-inch, 10-inch, and 12-inch, and originally they revolved at between seventy-five and eighty revolutions per minute (rpm). Most producers eventually settled on 78 rpm. A 10-inch disc would record about three minutes of music on each side. The discs used a spiral groove to more...

"Money cannot buy health, but I'd settle for a diamond-studded wheelchair." Dorothy Parker, writer After breaking his back in a mining accident , Herbert Everest so disliked his unwieldy wheelchair that he enlisted the help of an engineer friend, Harry Jennings, to help design a new chair. The device that Jennings came up with revolutionized the wheelchair market. Although wheelchairs had been in existence since the sixteenth century (the first one thought to be built for King Philip II of Spain), they had seen little development on their basic design until 1909. It was at around that time that the first lightweight models were made out of tubular steel rather than wood. These models had some foldable features, but it was the introduction of the folding X-brace frame that was the secret to Jennings's successful design. Beforehand, any wheelchairs that had foldable features used a T-shaped or an l-shaped frame. more...

U.S. inventor Otto Frederick Rohwedder (1880-1960) started working on the design of an automatic bread slicer in around 1912 and developed several prototypes, including one that held a sliced loaf together with metal pins. These early designs were not successful and Rohwedder faced a major setback in 1917 when his designs were destroyed in a fire at the factory at Monmouth, Illinois, that had agreed to build the first slicing machines. Rohwedder, having earlier trained as a jeweler, was employed by a security firm while working on the development phase of his invention in his spare time. He continued improving his designs and realized that the main challenge he faced was keeping the bread fresh, because after slicing the loaf went stale more quickly. By 1927 he had devised a machine that both sliced and wrapped the bread. The timing for the launch of the bread slicer was good: the more...


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