The History of the Telephone

Alexander Graham Bell and Elisha Gray raced to invent the telephone.

In the 1870s, two inventors Elisha Gray and Alexander Graham Bell both independently designed devices that could transmit speech electrically (the telephone). Both men rushed their respective designs to the patent office within hours of each other, Alexander Graham Bell patented his telephone first. Elisha Gray and Alexander Graham Bell entered into a famous legal battle over the invention of the telephone, which Bell won.

Alexander Graham Bell - Evolution of the Telegraph into the Telephone

The telegraph and telephone are both wire-based electrical systems, and Alexander Graham Bell's success with the telephone came as a direct result of his attempts to improve the telegraph.

When Bell began experimenting with electrical signals, the telegraph had been an established means of communication for some 30 years. Although a highly successful system, the telegraph, with its dot-and-dash Morse code, was basically limited to receiving and sending one message at a time. Bell's extensive knowledge of the nature of sound and his understanding of music enabled him to conjecture the possibility of transmitting multiple messages over the same wire at the same time. Although the idea of a multiple telegraph had been in existence for some time, Bell offered his own musical or harmonic approach as a possible practical solution. His "harmonic telegraph" was based on the principle that several notes could be sent simultaneously along the same wire if the notes or signals differed in pitch.

Alexander Graham Bell - Talk with Electricity

By October 1874, Bell's research had progressed to the extent that he could inform his future father-in-law, Boston attorney Gardiner Greene Hubbard, about the possibility of a multiple telegraph. Hubbard, who resented the absolute control then exerted by the Western Union Telegraph Company, instantly saw the potential for breaking such a monopoly and gave Bell the financial backing he needed. Bell proceeded with his work on the multiple telegraph, but he did not tell Hubbard that he and Thomas Watson, a young electrician whose services he had enlisted, were also exploring an idea that had occurred to him that summer - that of developing a device that would transmit speech electrically.

While Alexander Graham Bell and Thomas Watson worked on the harmonic telegraph at the insistent urging of Hubbard and other backers, Bell nonetheless met in March 1875 with Joseph Henry, the respected director of the Smithsonian Institution, who listened to Bell's ideas for a telephone and offered encouraging words. Spurred on by Henry's positive opinion, Bell and Watson continued their work. By June 1875 the goal of creating a device that would transmit speech electrically was about to be realized. They had proven that different tones would vary the strength of an electric current in a wire. To achieve success they therefore needed only to build a working transmitter with a membrane capable of varying electronic currents and a receiver that would reproduce these variations in audible frequencies.

First Sounds - Twang

On June 2, 1875, Alexander Graham Bell while experimenting with his technique called "harmonic telegraph" discovered he could hear sound over a wire. The sound was that of a twanging clock spring.

Bell's greatest success was achieved on March 10, 1876, marked not only the birth of the telephone but the death of the multiple telegraph as well. The communications potential contained in his demonstration of being able to "talk with electricity" far outweighed anything that simply increasing the capability of a dot-and-dash system could imply.

First Voice - Mr. Watson, come here. I want to see you.

Alexander Graham Bell's notebook entry of 10 March 1876 describes his successful experiment with the telephone. Speaking through the instrument to his assistant, Thomas A. Watson, in the next room, Bell utters these famous first words, "Mr. Watson -- come here -- I want to see you."




This model of Bell's first telephone (right) is a duplicate of the instrument through which speech sounds were first transmitted electrically (1875). Alexander Graham Bell

The Wright Brothers - First Flight

In 1899, after Wilbur Wright had written a letter of request to the Smithsonian Institution for information about flight experiments, the Wright Brothers designed their first aircraft: a small, biplane glider flown as a kite to test the


ir solution for controlling the craft by wing warping. Wing warping is a method of arching the wingtips slightly to control the aircraft's rolling motion and balance.

The Wrights spent a great deal of time observing birds in flight. They noticed that birds soared into the wind and that the air flowing over the curved surface of their wings created lift. Birds change the shape of their wings to turn and maneuver. They believed that they could use this technique to obtain roll control by warping, or changing the shape, of a portion of the wing.

Over the next three years, Wilbur and his brother Orville would design a series of gliders which would be flown in both unmanned (as kites) and piloted flights. They read about the works of Cayley, and Langley, and the hang-gliding flights of Otto Lilienthal. They corresponded with Octave Chanute concerning some of their ideas. They recognized that control of the flying aircraft would be the most crucial and hardest problem to solve.

Following a successful glider test, the Wrights built and tested a full-size glider. They selected Kitty Hawk, North Carolina as their test site because of its wind, sand, hilly terrain and remote location.

In 1900, the Wrights successfully tested their new 50-pound biplane glider with its 17-foot wingspan and wing-warping mechanism at Kitty Hawk, in both unmanned and piloted flights. In fact, it was the first piloted glider. Based upon the results, the Wright Brothers planned to refine the controls and landing gear, and build a bigger glider.



In 1901, at Kill Devil Hills, North Carolina, the Wright Brothers flew the largest glider ever flown, with a 22-foot wingspan, a weight of nearly 100 pounds and skids for landing. However, many problems occurred: the wings did not have enough lifting power; forward elevator was not effective in controlling the pitch; and the wing-warping mechanism occasionally caused the airplane to spin out of control. In their disappointment, they predicted that man will probably not fly in their lifetime.

In spite of the problems with their last attempts at flight, the Wrights reviewed their test results and determined that the calculations they had used were not reliable. They decided to build a wind tunnel to test a variety of wing shapes and their effect on lift. Based upon these tests, the inventors had a greater understanding of how an airfoil (wing) works and could calculate with greater accuracy how well a particular wing design would fly. They planned to design a new glider with a 32-foot wingspan and a tail to help stabilize it.

During 1902, the brothers flew numerous test glides using their new glider. Their studies showed that a movable tail would help balance the craft and the Wright Brothers connected a movable tail to the wing-warping wires to coordinate turns. With successful glides to verify their wind tunnel tests, the inventors planned to build a powered aircraft.

After months of studying how propellers work the Wright Brothers designed a motor and a new aircraft sturdy enough to accommodate the motor's weight and vibrations. The craft weighed 700 pounds and came to be known as the Flyer.

The brothers built a movable track to help launch the Flyer. This downhill track would help the aircraft gain enough airspeed to fly. After two attempts to fly this machine, one of which resulted in a minor crash, Orville Wright took the Flyer for a 12-second, sustained flight on December 17, 1903. This was the first successful, powered, piloted flight in history.

In 1904, the first flight lasting more than five minutes took place on November 9. The Flyer II was flown by Wilbur Wright.

In 1908, passenger flight took a turn for the worse when the first fatal air crash occurred on September 17. Orville Wright was piloting the plane. Orville Wright survived the crash, but his passenger, Signal Corps Lieutenant Thomas Selfridge, did not. The Wright Brothers had been allowing passengers to fly with them since May 14, 1908.

In 1909, the U.S. Government bought its first airplane, a Wright Brothers biplane, on July 30. The airplane sold for $25,000 plus a bonus of $5,000 because it exceeded 40 mph.



In 1911, the Wrights' Vin Fiz was the first airplane to cross the United States. The flight took 84 days, stopping 70 times. It crash-landed so many times that little of its original building materials were still on the plane when it arrived in California. The Vin Fiz was named after a grape soda made by the Armour Packing Company.

In 1912, a Wright Brothers plane, the first airplane armed with a machine gun was flown at an airport in College Park, Maryland. The airport had existed since 1909 when the Wright Brothers took their government-purchased airplane there to teach Army officers to fly.

On July 18, 1914, an Aviation Section of the Signal Corps (part of the Army) was established. Its flying unit contained airplanes made by the Wright Brothers as well as some made by their chief competitor, Glenn Curtiss.

That same year, the U.S. Court has decided in favor of the Wright Brothers in a patent suit against Glenn Curtiss. The issue concerned lateral control of aircraft, for which the Wrights maintained they held patents.

Although Curtiss's invention, ailerons (French for "little wing"), was far different from the Wrights' wing-warping mechanism, the Court determined that use of lateral controls by others was "unauthorized" by patent law.

petronas tower:

PETRONAS Twin Towers or alternatively known as Petronas Towers was the world’s tallest building from 1998 to 2004, until it was surpassed by Taipei 101. The tower itself is located at Kuala Lumpur, Malaysia with 88 habitable floors and 452 meters in height when measured from the main entrance to its pinnacle.
Nevertheless, the PETRONAS Twin Towers are the tallest twin towers in the world and is recognized as being the world’s tallest high rise of the 20th century.
The prominent features of the towers are the double-decked sky bridge, pinnacles and an advanced elevator system. Themain use of the building is for office space, although below the twin towers is Suria KLCC, a popular shopping mall and Dewan Filharmonik Petronas, the home of the Malaysian Philharmonic Orchestra.

The architectural design of the Petronas Twin Towers floor plan is based on simple Islamic geometric squares creating a shape of eight-pointed stars, reflecting unity within unity, harmony, stability and rationality.
To create more space, eight semi-circles were superimposed in the inner angles of the interlocked squares.
These semicircles are themselves anchored by the main structural columns of the buildings. The twin towers are symmetrically aligned and are connected with a suspended sky bridge.
The design details became prominent as the building rise in height towards the pinnacles. To maintain the vertical axis of the design, the towers are set back five times.

In the beginning, a race track was removed by the government as a move to ease the traffic congestion in that area. This opens up a 40ha piece of land worth hundreds of millions of ringgit, in the heart of KL free for redevelopment. With Petronas securing the financing of the development, Datuk Seri Dr Mahathir Mohammad, Prime Minister at that time wanted a building that would be identifiably Malaysian, that was of world class standards and which Malaysians could be proud of. Thus, an international design competition was held, with eight international firms invited. Finally, Cesar Pelli’s design, two slim 88-storey tower with a skybridge won the competition.
At first, there were no plans for the Petronas Towers to become the highest building in the world until Dr Mahathir suddenly thought of it; even during the building is already under construction. Mathematical recalculations were done and finally the plan to raise the height ofthe pinnacles is passed.

Construction started in 1993, with the piling of the world’s deepest foundations. The construction was done by two different contractors, sparking competition against each other. On the other hand, the towers were constructed with super high strength reinforced concrete due to the high cost of stete

At the top of the Petronas Twin Towers are structural steel pinnacles, which stood 73.5m tall. As two different contractors worked on the pinnacles, therefore one was made in Japan and the other South Korea.
Each pinnacle is composed of a spire, mast ball and ring ball. The ring ball consisted of 14 concentric tubes of differing diameters. In overall, the pinnacle is made up of 50 unique elements, lifted all piece by piece into place, making up a single 176 tonne in weight.
Functionally speaking, the pinnacle assembly are used to store aircraft warning lights and window washing equipment for the towers.

It was aIso the twin towers’ pinnacles that crowned the towers as the world’s tallest building in 1998 defined by the Council of Tall Buildings and Urban Habitat. This sparked controversy as the Sears Tower of USA is taller thanPetronas Twin Towers in the number of floors. However, under the rules used for rating the world’s tallest buildings, architectural spires count towards building height, while antennas atop a building do not.

The most prominent feature of the towers is the double-decked skybridge on the 41st and 42nd floors. The bridge is170m high and 58m long, providing access between the towers.

Center of skybridge as the observation deck with a circular window on top.

Interior of the skybridge on 42nd floor. The skybridge is open to all visitors.
Most high-rise buildings in the world use steel elements in their construction, but concrete was used instead of conventional steel in the construction of columns and core walls of the towers. Concrete was opted since it was a localmaterial that could be produced easily and Malaysia is quite sophisticated in concrete production which had ready labour in the industry. Besides, reinforced concrete also has twice the ability of steel to withstand vibrations.
To withstand 300,000 metric tonnes, a large concrete slab is used together with friction piles reinforced by grout (a mixture of sand and cement).

The polished facade is done with stainless steel extrusions and laminated glass covering or cladding the walls, reflecting Pelli’s vision of “multi-faceted diamond sparkling in the sun.” This minimizes heat gain by reflecting harmful UV light and unwanted solar radiation.

Each of the towers is supported by sixteen cylindrical columns that is made of concrete, encircling the core in the centre. They are placed on the inner corners of the star shaped plan with columns linked by slightly arched ring beams, also of concrete. The core and cylindrical frame system is constructed from in-situ high-strength concrete, including smaller perimeter columns around the two bustles. Some structural steel was used for typically long span floor beams to support concrete-filled metal deck slabs.

Horizontal steel bars or ‘teardrop’ and ‘bullnose’ steel sections are built into the polished facade which frames and linesthe open glass area. These sun screen brackets provide shade for the building and provide the appearance of flowing silver ribbon.
“For the Petronas Twin Towers, I tried to express the essences of the country. The building is rooted in tradition, but it is mostly about Malaysia’s aspiration and ambition,” said architect Cesar Pelli.

Petronas Towers

At a staggering 452 meters in height the Petronas Towers dominate the skyline in Kuala Lumpur. The Petronas Towers are the worlds “tallest freestanding” towers in the world housing an assortment of office buildings, a contemporary concert hall and the Malaysian Philharmonic Orchestra in the Petronas Malaysia Philharmonic Hall. The geometric impressions on both towers are often found in Islamic architecture. Two overlaid and rotated squares each encompass small, rounded in fillings adorned on the Petronas Towers. Many architects describe this special pattern as symbolizing stability, unity, harmony and rationale which are all important Islamic principles. Special highlights of the Petronas Towers include high-speed double deck elevators and an exciting double deck Sky Bridge.
The Petronas Towers are joined only at the 41st and the 42nd floor where the Sky Bridge is. Walking along the Sky Bridge is one of the main events when on a Malaysia tour of this captivating development. The bridge spans an astonishing 192 feet. There is a tour of the Sky Bridge available at Petronas Malaysia where you can enjoy a panoramic city view below. The tour is a short 10 minutes and leads up to the bridge. The best time to go is early in the morning to beat the long lines that can develop. Tickets are handed out on a first-come-first-served basis and you can choose the tour time when you get tickets. The Sky Bridge is open from 9:00am to 5:00pm from Tuesday through Sunday and is free.
Inside the Petronas Twin Tower Kuala Lumpur merchants line the first few floors. There are also arcades, and an assortment of restaurants. There is an interesting Science Museum you can visit that’s great when on a family-oriented Malaysia holiday. Kuala Lumpur attractions nearby are easily visited after a climb to the top of the Petronas Twin Tower during a Malaysia vacation. When visiting the Petronas Twin Tower Kuala Lumpurs city center will surround you with many more beautiful buildings. Often called a “city within a city” the area is large and stretches in every direction.
Situated between the Petronas Towers is one of the best shopping destinations in Kuala Lumpur, Suria KLCC, containing a huge array of merchandise to peruse. With six levels to explore a trip here can easily eat up an entire day if you like to shop! The Mandarin Oriental is due south of Suria KLCC and is considered to be the most affluent of Kuala Lumpur hotels. Though many can’t afford the high costs to stay, if you really wish to see the elegant interior try one of their restaurants for a five star dining experience.
In the immediate vicinity, the Kuala Lumpur Convention Center can also be found. In addition to hosting many international events and trade shows The Aquaria Oceanarium is also inside. This is said to be the biggest aquarium in the world. It features more than 5,000 marine and aquatic animals with exhibits highlighting 150 native and international species. The Batu Cave is a major attraction in the city and not to be missed when in the area.
The KLCC Park is a wonder in itself, a massive green space in the middle of a huge and bustling city, much like Lumphini Park in Thailand. Don’t miss it after visiting Petronas Malaysia. The park is an attraction for the many things to do among the beautifully landscaped areas. With breathtaking views of Petronas Twin Tower, Kuala Lumpur shines in all her glory. Relaxing rest areas, a child’s pool, jogging track, Symphony Lake Fountains and more can all be found on the grounds. Many locals frequent the area during lunch time and visitors from all over the world walk the grounds admiring the beautiful pairing of nature with man’s creation.
Sprawling over 50-acres, the tropical gardens and lush foliage offer a haven of serenity and a respite from the dynamic and ever-busy inner city.

Great Wall of China

Great Wall of China

Theresa Muzzillo
Great Wall of China
The Great Wall of China was very important in China throughout history. It was built and re-modeled throughout many historical dynasties of China. The Great Wall of China was built for several different reasons. It was constructed for protection from northern invaders; it partially unified China, and was later restored for the attraction of travelers.

There were several different dynasties that made what the Great Wall is today. The first dynasty to begin the construction of the Great Wall was the Qin Dynasty (221-206 B.C.). Shihuangdi built the Great Wall as a defense from northern invaders (7). Weapons of this time, such as arrows, could not reach over the extensive wall. The workers of the Qin Dynasty worked day and night (6). If they complained or attempted to run away and got caught, they suffered severe consequences of being buried alive (6). Most of the workers spent their whole lives building this wall (6) and about 70% of the China population was involved with the construction of this wonder (4). Why were so many people involved in this construction? The Great Wall was unifying China as a country inside the walls. After the Qin Dynasty, construction of the Great Wall didn’t stop. To see more on the Qin Dynasty, click here.

The Han Dynasty (202 B.C.- A.D. 220) continued to add onto and restore the construction of the Qin Dynasty. They extended the wall over 300 more miles through the Gobi Desert using materials such as twigs, red willow reeds, water and fine gravel (4). The Han Dynasty also built beacon towers that were placed about 15-30 miles apart along the wall. Smoke signals from columns were used to warn the defenders of an attack (4). There were several advancements made to the Great Wall in the Han Dynasty that improved and "updated" the wall. The reconstruction did not stop here. It continued into the Ming Dynasty (1368-1644). To see more on the Han Dynasty, click here.
The Ming Dynasty was when most of the reconstruction was made and the crumbling walls were rebuilt (4). They added many miles to what already existed in addition to restoring it. The Ming Dynasty built more of the wall than any other dynasty before it. Along with their extensive addition, they built the wall with huge heavy bricks made from clay (6) and granite blocks (1). If all the bricks were taken from only the portion of the wall built during the Ming Dynasty, they would circle the Earth at the equator in a wall five feet high and three feet thick. Modern canons were built along the wall in strategic locations and the watchtowers were redesigned with sophistication (1). To see more on the Ming Dynasty, click here.

After the Ming Dynasty reconstructed the wall for over 200 years, it is now only being restored for the attraction of travelers (4). Throughout the 1,000 years of construction of the Great Wall, 3,000 people died building it. That is more than 300 people per mile (4). After about 2,500 years of the Great Wall standing, it has extended over 6,000 miles at one point reaching from the Yalu River in Northeast China, to Gansu province in Northwest China (5). The actual length of the Great Wall varies from different authors, but it ranges from 3,000 to 4,500 miles (3/4). The actual length of the Great Wall was at one time 6,000 miles long. After lots of vandalism and erosion, the wall has reduced to become what it currently is now.

The Great Wall of China was built for several different reasons. In the Qin Dynasty, Shihuangdi built it for two different main reasons. One was to block the raids from the north, known as Central Asia. The second reason was China thought they were too "civilized" and they should be separated from the "barbaric" countries physically and culturally (Waldron). The Great Wall only protected China from the little invasions, so the Han Dynasty and Ming Dynasty extended onto the wall and increased its size in hope of preventing more invasions. This didn’t help very much because as the wall was developing, there were more advancements in weapons too. The Wall was especially helpful to warn China of invasions because they could see armies from their watchtowers. Re-modeling with advancements such as watchtowers and beacons helped to reach the main reason of building the wall... keeping out invaders (McNeese). After the Ming Dynasty, there was not a whole lot of reconstruction for reasons of protection from invaders. The main reason the Great Wall has been repaired in certain areas is for the attraction of travelers.

The Great Wall of China attracts an extensive amount of travelers every year. What attracts travelers to the Great Wall? It is such a great attraction for many different reasons. The wall is about 3,750 miles long and can even be seen from the moon (McNeese 12). The Great Wall is crumbling and some of it has been restored in areas such as Beijing because it is the most visited area and they want to keep it open to travelers. At one point the wall extended over 6,000 miles long. Travelers walk across the Great Wall of China where originally the width of the wall could fit 5 horse riders or 10-foot soldiers walking shoulder to shoulder (Feinstein 13). One of the highest points of the Great Wall is 35 feet tall. Many travelers are attracted to the watchtowers that are every 100-200 yards (Fryer 2). Each watchtower was about 40 feet high (Fryer 2). The Great Wall is made of granite blocks, stone and sometimes brick. This is interesting because of the way China adapted to the materials in their surroundings. Depending on the location of the wall determined what material to use. In the hill areas of the West, it is made of moistened earth materials and then pounded solid since stone and brick were scarce here. Not only are all these breath-taking features interesting, but the Wall also contained the amazing Ming Tombs. To see more on the Ming Tombs, click here. The Great Wall has been restored and fixed up throughout History to become what it is now and travelers walk across it as if it were one of the Seven Wonders of the World. After all these fascinating heights and lengths, I can understand why so many people would love to see the Great Wall.

The Great Wall went through over 1,000 years of being built and reconstructed through several different dynasties. In each dynasty, the Wall was repaired, "modernized", and added on to for different reasons. Even after those dynasties have fallen, the Great Wall is still being repaired and for yet another reason as to attract tourists and sightseers to the extravagant wonder. With all the amazing sights of the 40 foot watchtowers and extensive, perpetual walls… who wouldn’t want to visit the Great Wall?!?!

The Great Wall of China

The first major wall was built during the reign of Qin Shi Huangdi, the first emperor of China during the Qin (Ch'in) Dynasty (221 B.C - 206 B.C.). It was created by joining several existing walls built previously by regional governments. This first wall was built much further north than the current Great Wall, and made of materials that have largely dissappeared over time.
The Great Wall that can still be seen today was built during the Ming Dynasty (1368-1644), on a much larger scale and made of stone on the sides and top. The wall housed garrisons, signal fires, and a messenger and postal service. The primary purpose was to make it difficult and slow for nomadic armies to get their horses across the wall. Without their horses the Huns were not a serious military threat. It is 4000 miles long, or 6400 km., and is visible from Earth orbit.

Taj Mahal from the Gate