Wilbur Wright

Wilbur Wright (1867-1912), American aeronautical engineer who worked with his brother, Orville Wright, to build and fly the first airplane.

Wilbur, the elder of the two brothers, was born in Millville, Indiana. He was the third of five Wright children. Their father was a bishop of the United Brethren Church. Wilbur went to high school in Dayton, Ohio, with his brother Orville. The boys shared an interest in mechanical things and learned as much about mathematics and engineering as they could. Wilbur left high school before finishing his courses, and neither brother formally graduated. After leaving school, the brothers made several attempts at editing and printing small local newspapers. In 1892 they formed the Wright Cycle Company. For the next ten years they designed, built, and sold bicycles.

The Wright brothers must have been aware of the possibility of powered flight and some of the efforts being made toward that end. The work of German aeronautical pioneer Otto Lilienthal in the 1890s inspired the Wrights to pursue their own glider and airplane designs. Lilienthal died in a glider crash in 1896, convincing Wilbur that the stability of the design and the skill of the pilot were as important as getting an airplane into the air.

The Wright brothers concentrated on developing techniques to stabilize and provide directional control for their gliders from 1896 to 1899. In August 1899 they flew a kite with a wingspan of about 1.5 m (5 ft). The kite incorporated controls that could twist the ends of the wings. This wing-warping technique provided stability and directional control and was the forerunner of the idea of ailerons. Ailerons are flaps on the trailing edges of modern airplane wings that move independently of the wings to provide stability and steering controls. See Airplane: Control Components.

In 1900 the Wrights built a larger kite with a 5-m (17-ft) wingspan that could carry a pilot. They decided to begin their test flights near Kitty Hawk, North Carolina, because the steady winds provided power for their flights and the sandy banks made crashing safer for machines and pilots. The kite flew well and even carried Wilbur for a few seconds of piloted flight.

In July 1901 they returned to Kitty Hawk and built a wooden glider that had sledlike runners. They worked at Kill Devil Hills, where there were large sand dunes over which the runners could glide. Their new machine was longer than the previous model and its wings were arched differently. It also had a hand-operated elevator—a flap on the horizontal stabilizer on the tail that could control up-and-down movement. The brothers again achieved encouraging results, particularly after they experimented with other wing arches. However, there were still problems with stability and control.

During late 1901 and early 1902 the Wrights built a small wind tunnel and tested various wing designs and wing arches. In the course of these tests, they compiled the first accurate tables of lift and drag, the important parameters that govern flight and stability. They constructed a new glider with a 10 m (32 ft) wingspan in mid-1902. At first the glider had two vertical fins mounted behind the wings. The brothers still found it difficult to turn with this design, so they transformed the double fin to a single moveable rudder at the rear of the glider. This configuration proved so successful that they decided to attempt powered flight the following summer.

During late 1902 and early 1903 they searched in vain for a suitable engine for their craft and for knowledge of propeller design. No existing engines that provided the power required were light enough to be practical to carry aboard an airplane. They eventually constructed their own 9-kilowatt (12-horsepower) motor and made their own propeller, which moved air very efficiently. After some initial trouble with the propeller shafts, the first Wright Biplane took to the air and made a successful flight on December 17, 1903, at Kill Devil Hills near Kitty Hawk. The airplane had a wingspan of 12 m (40 ft) and weighed 340 kg (750 lb) with the pilot. The two brothers took turns flying the plane. Wilbur, in the last of the flights, stayed in the air for 59 seconds and traveled 260 m (852 ft) at speeds a little under 16 km/h (10 mph).

The following year the Wrights replaced the engine with a more powerful 12-kilowatt (16-horsepower) engine and separated the rudder controls from the controls that changed the shape of the wing. They tested their new model in their hometown of Dayton, learning to make longer flights and tighter turns.

In 1905 the Wrights were sufficiently confident of their design to offer it to the United States War Department. The following year they patented their control system, including the elevator, rudder, and wing-warping controls. Although they spent time patenting and finding markets for their machines during the next few years, they did not feel sufficiently confident to exhibit their airplanes publicly until 1908. That year Wilbur demonstrated the plane in France, while Orville flew in the United States. In 1909 Wilbur flew in Italy and Orville in Berlin, Germany. The airplanes were now sufficiently well controlled and stable enough to allow Wilbur to make a flight of 32 km (20 miles) in the United States.

During the next few years the brothers and their Wright Company continued building airplanes, but their competitors gained ground. In 1912 Wilbur died in Dayton, Ohio, of typhoid fever. By 1918 the Wrights’ patents were under pressure.

Robert Boyle

Introduction:

Robert Boyle (1627-1691), English natural philosopher and one of the founders of modern chemistry. Boyle is best remembered for Boyle’s law, a physical law that explains how the pressure and volume of a gas are related. He was instrumental in the founding of the Royal Society, a British organization dedicated to the advancement of the sciences. Boyle was also a pioneer in the use of experiments and the scientific method to test his theories.

II.

BOYLE’S LIFE

Boyle was born in Lismore Castle in Lismore, Ireland. His father was Richard Boyle, who was the first earl of Cork. Robert learned to speak French and Latin as a child and went to Eton College in England at the early age of eight.

In 1641 Boyle began a tour of Europe, returning to England in 1644. He settled there, because Ireland was in turmoil over colonization efforts by English protestants. Boyle had inherited parts of several estates upon his father’s death in 1643, and income from these allowed him to live independently. He joined a group known as the Invisible College, whose aim was to cultivate ideas called the “new philosophy.” The new philosophy included new methods of experimental science, in which scientists sought to prove or disprove hypotheses through careful experiments. Boyle moved to Oxford, which was one of the meeting places of the Invisible College, in 1654. King Charles II granted a charter in 1663 that allowed the Invisible College to become the Royal Society of London for Improving Natural Knowledge, and Boyle was a member of its first council. (He was elected president of the Royal Society in 1680, but declined the office.) He moved to London in 1668 and lived with his sister until his death in 1691.

III.

BOYLE’S WORK

	Gas Laws of Boyle and Charles With their discovery of the gas laws that bear their names, Robert Boyle and Jacques Alexandre Charles made important contributions to chemistry. In 1661 English scientist Robert Boyle found that the volume of a gas varies inversely with its pressure, if the temperature is held constant. About a hundred years later, a French physicist, Jacques Alexandre Charles, observed that the volume of a gas varies in proportion to its temperature, if the pressure is held constant. Encarta Encyclopedia © Microsoft Corporation. All Rights Reserved.
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Boyle carried out his most active research while he lived in Oxford. Much of his research dealt with the behavior of gases, including the earth’s atmosphere. By careful experiments, he established Boyle’s law. Boyle’s law states that the volume of a given amount of gas varies inversely with its pressure, if temperature is constant. This means that at a constant temperature, the pressure of a gas will increase as the volume of the gas is decreased, and vice versa. Boyle determined the density of air in the earth’s atmosphere and pointed out that the weight of objects varies with changes in atmospheric pressure. He compared the lower layers of the earth’s atmosphere to a number of sponges or small springs that the weight of the layers above compresses. In 1660 Boyle published these findings in a book entitled The Spring of Air.

Alexander Graham Bell

Alexander Graham Bell (1847-1922), American inventor and teacher of the deaf, most famous for his work on the telephone.

Bell was born on March 3, 1847, in Edinburgh, Scotland, and educated at the universities of Edinburgh and London. He immigrated to Canada in 1870 and to the United States in 1871. In the United States he began teaching deaf-mutes, publicizing the system called visible speech. The system, which was developed by his father, the Scottish educator Alexander Melville Bell, shows how the lips, tongue, and throat are used in the articulation of sound. In 1872 Bell founded a school to train teachers of the deaf in Boston, Massachusetts. The school subsequently became part of Boston University, where Bell was appointed professor of vocal physiology. He became a naturalized U.S. citizen in 1882.

Since the age of 18, Bell had been working on the idea of transmitting speech. In 1874, while working on a multiple telegraph, he developed the basic ideas of the telephone. His experiments with his assistant Thomas Watson finally proved successful on March 10, 1876, when he transmitted: “Watson, come here; I want you.” Subsequent demonstrations, particularly one at the 1876 Centennial Exposition in Philadelphia, Pennsylvania, introduced the telephone to the world and led to the organization of the Bell Telephone Company in 1877.

In 1880 France bestowed on Bell the Volta Prize, worth 50,000 francs, for his invention. With this money he founded the Volta Laboratory in Washington, D.C., where, in that same year, he and his associates invented the photophone, which transmits speech by light rays. Other inventions include the audiometer, used to measure acuity in hearing; the induction balance, used to locate metal objects in human bodies; and the first wax recording cylinder, introduced in 1886. The cylinder, together with the flat wax disc, formed the basis of the modern phonograph.

Bell was one of the cofounders of the National Geographic Society, and he served as its president from 1896 to 1904. He also helped to establish the journal Science by financing it from 1883-1894.

After 1895 Bell's interest turned mostly to aeronautics. Many of his inventions in this area were first tested near his summer home at Baddeck on Cape Breton Island in Nova Scotia, Canada. His study of flight began with the construction of large kites, and in 1907 he devised a kite capable of carrying a person. With a group of associates, including the American inventor and aviator Glenn Hammond Curtiss, Bell developed the aileron, a movable section of an airplane wing that controls roll. They also developed the tricycle landing gear, which first permitted takeoff and landing on a flying field. Applying the principles of aeronautics to marine propulsion, his group started work on hydrofoil boats, which travel above the water at high speeds. His final full-sized “hydrodrome,” developed in 1917, reached speeds in excess of 113 km/h (70 mph) and for many years was the fastest boat in the world.

Bell's continuing studies on the causes and heredity of deafness led to experiments in eugenics, including sheep breeding, and to his book Duration of Life and Conditions Associated with Longevity (1918). He died on August 2, 1922, at Baddeck, where a museum containing many of his original inventions is maintained by the Canadian government.