The Eiffel Tower , initially named “Tower of 330 meters”, is the undisputed symbol of Paris , France and Europe . It is surely the first thing that comes to mind when thinking of Paris . This tower, thought and built in the “crazy years”, little by little gained that privileged place that until then only the Arc de Triomphe , the Notre Dame Cathedral and the Louvre were disputed. It was built in two years, two months and five days in controversy with the artists of the time, who saw it as an iron monster. Initially used for army tests as communication antennas, today it serves, in addition to being a tourist attraction, as a radio and television program station.
General characteristics
The Eiffel Tower was built for the Universal Exhibition of 1889 to be held in commemoration of the centenary of the French Revolution . Gustave Eiffel and his company were the entrepreneurs of such a project that, beginning in 1887, was completed in March 1889 , just over two years later.
The work generated many controversies, especially among the artists of the time, who thought of the tower as an “iron monster” in the middle of the city of romanticism. Even before the Tower was finished, a petition signed by 300 leading artists (one for each meter in height) was presented to the city government protesting the “futility and monstrosity of the Eiffel Tower” 2. The signatories sarcastically used the name “Eiffel Tower” (Eiffel meant “the 300m tower”), but the name took effect and today the Eiffel Tower is universally recognized as the symbol of Paris and currently decorates French banknotes of 200 francs.
If we talk about technical characteristics, the tower is a huge metal structure that weighs about 10,000 tons and its height, initially 300 meters, is currently 324 meters, including the radio and television antenna that was added much later. It consists of four arched legs that taper inwards, forming a single column that reaches its maximum height at 275 m (there are two other levels at 57 and 115 m).
Some 200 workers worked there, joining more than 18,000 pieces of iron with 2 and a half million bolts. The foundations reach 30 meters deep, due to the proximity to the river and the nature of the subsoil. Composed of three levels, the first two can be accessed by stairs; it will take breath to climb the 1665 steps! Otherwise you can take the elevator, which normally has long waiting lines …
Tower levels
On the first level, at 57 meters high, there is a post office, from where you can send postcards with the special stamp “Paris Tour Eiffel”, the restaurant “Altitude 95”, a souvenir shop, the reception room and conferences “Gustave Eiffel”, the Cineiffel, exhibitions with photos of the tower, and of course the gallery from which you can take panoramic photos of Paris.
The second level is 115 meters above the ground and the elevator that leads to the third level departs from there . There are some souvenir shops, the “Jules Verne” restaurant and above all, the panoramic views of the city that are spectacular.
At 276 meters, after climbing 160 meters in the elevator, you reach the third level, where the views are absolutely extraordinary. On this level is a recreation of Gustave Eiffel’s workplace, with wax figures of Eiffel and his daughter Claire welcoming the inventor Thomas Edison , as well as Gustave Eiffel and his two engineers, Maurice Koechlin and Emile Nouguier. The upper level contained a few rooms used by Eiffel, including an office where he received Thomas Edison in 1899, a spiral staircase and a flagpole at the end, which brought the initial height up to 312 meters.
Tower Physics
The characteristic shape of the Tower is based on basic physics and was designed so that the maximum moment generated by the wind was compensated by the moment of the weight of the Tower. The equality of the moments allows to calculate the curvature of the edges so that they offer the most efficient resistance to the wind. Each edge of the Tower is shaped such that “the composition of the vertical force of the actual weight of the Tower and the horizontal force of the wind give at each level a force directed exactly along the desired leg.”
To achieve this balance, Eiffel had to “build the curved legs, in such a way that the tangents to them, drawn at points at the same height, always intersect at the point through which the resulting wind force passes over the part that is above the points in question ”. In modern terms, the Eiffel condition says that the moment due to the wind in any part of the Tower, from a given height to the top is equal to the moment of the weight of that same part.
As Eiffel explained, “all the wind shear forces go through the inside of the main legs. The tangent lines to each leg with the point of tangency at the same height, will always intersect a second point, which is exactly the point through which the flow resulting from the action of the wind passes over the part of the Tower support located by above the two points in question. Before reaching the cusp, the legs suddenly leave the ground, and in such a way that they are shaped by the action of the wind ”5
History
Conceived in 1884 , built between 1887 and 1889 and inaugurated for the Universal Exhibition of 1889 in Paris , the Eiffel Tower today symbolizes an entire country, France . However it was not always so. The Eiffel Tower was part of the economic showcase of the country.
Since 1875 , the nascent Third Republic, characterized by chronic political instability, could hardly be sustained. In government, political parties succeed one another at a steady pace. According to León Gambetta, it is often made up of “opportunistic” ministers, but whose legislative work laid the stones of the principles still in force today: compulsory school, secularism, freedom of the press, etc.
But the society of the time pays even more attention to technical progress and social progress. It is this belief in the benefits of science that gave rise to world expositions. But from the first exhibition (Great Exhibition of the Works of Industry of All Nations, London, 1851), the rulers quickly perceive that behind the technological setting a showcase is emerging. politics, and it would be a mistake not to seize the opportunity.
By demonstrating its industrial prowess, the host country shows its advancement and superiority over other European powers, then ruling the world. Under this vision, France repeatedly hosts the World’s Fair, in the years 1855 , 1867 and 1878 . Jules Ferry, president of the Council from 1883 to 1885 , decides to revive the idea of holding a universal exhibition in France. On November 8, 1884 , he signed a decree that officially establishes the celebration of a Universal Exhibition in Paris from May 5 to October 31, 1889. The chosen year was not random, because it symbolizes the centenary of the French Revolution. Paris is once again the “center of the world.”
Although on the New World side, things evolve rapidly and it is on the other side of the Atlantic, within the young economic power of the United States of America, where the idea of a 300-meter tower will truly be born. Indeed, at the time of the Universal Exhibition in Philadelphia in 1876 , the American engineers Clark and Reeves, imagined a project of a cylindrical pole of 9 meters in diameter supported by metal shrouds, anchored in a circular base of 45 meters in diameter, with a total height of 300 meters. Due to lack of credits, his project will never see the light of day, although it would be published in France in the journal Nature.
In the same situation, the French engineer Sébillot brought up, in the United States , the idea of an iron “sun-tower” that would illuminate Paris . To do this, he joined forces with the architect Jules Bourdais, who was working on the project of the Trocadero Palace for the Universal Exhibition of 1878 . Together, they will conceive a project of a granite “tower-lighthouse”, 300 meters high, that will know several versions, which will compete with Gustave Eiffel’s tower project, and finally, it will never be built.
In accordance with the terms of the original contract, the Tower was established to stand for only 20 years; you even had to pay an entrance fee. To avoid demolition, Eiffel proved its usefulness in aerodynamics (he installed a wind tunnel in 1909 and spent many years engaged in aerodynamic experiments), meteorology (initially there was a station at the top of the Tower) and as a radio and telegraphy tower. (cunningly interested the military). The fact that millions of people still visit the Tower annually, after a hundred years open, is a testament to Eiffel’s influence and skill as an engineer.
As soon as the Tower was opened in 1899, it was visited by the President of the French Republic. Surely your interest motivated the appearance of the names of 72 French scientists permanently exposed in the first level. Some of the most famous and important names in the history of Physics and Mathematics are there, including his grandfather Lazarus, remembered for his works in mechanics, engineering and geometry. Perhaps seeing this family name displayed in such a technological marvel brought to the President’s mind the name of another member of his family, his uncle (son of Lazarus) and famous namesake, French physicist Sadi Carnot.
Curiosities
- Opening ceremony: 31 of March of 1889 and was opened to the public on May 6 of that year.
- Material: wrought iron
- Number of pieces: 18038
- Number of rivets: 2500000
- Steps: 1665
- Total weight: 10000 tons
- Panoramic elevators: 7
- Platforms with viewpoint: 3
- In the original project, it measured 350 meters for fear of falling, it was made its current size (324 meters.)
- At the end of the exhibition, it was going to be demolished, but it was saved thanks to the radio transmission tests carried out by the French army on it. Despite the complaints and criticisms from Parisians, it has become the symbol of Paris and is currently among the most visited monuments in the world.
- It is painted every 7 years with 60 tons of paint, 1500 brushes and a team of 25 skilled workers in acrobatic climbing.
- It is illuminated by 352 1000 Watt projectors , 200,000 fixed bulbs, four reflectors of powerful light that rotate at the top and 800 intermittent spotlights.
- The highest point can move up to 18 centimeters to one side or the other.
- The Eiffel family was of German origin, and they changed their surname (Bonickhausen) to Eiffel at the beginning of the 18th century
- The Eiffel Tower is the tallest structure in Paris (the second is the Tour Montparnasse), and the fifth tallest in France and was the tallest building in the world until the construction of the Chrysler Building , New York , in 1930 . Interestingly, the Tower is now taller than the Chrysler (because of the 24-meter antenna that was added to the Tower in 1900 ).
- Lightning struck the Tower in 1902 , causing extensive material damage.
- It is the most visited monument in the world, with 6,428,441 visits in 2005 .
- Since its construction, more than 200 million people have visited it. This figure was reached in 2002 .
- The co-architects of the Eiffel Tower were Émile Nougier , Maurice Koechlin and Stephen Sauvestre .
- The names of 72 illustrious French scientists are engraved on the Tower. Among them Auguste Jean Fresnel Jean-Baptiste Joseph Fourier , Ampère , Coulomb and Cauchy .
- Near the end of the Tower there are some rooms in which Gustave Eiffel himself lived.
- There are at least 17 reproductions of the Tower around the world. The largest is 165 meters (in Las Vegas ) and the smallest 3 meters (Paris, Michigan ).
- In July of 2003 there was a fire in the upper level of the tower. The Tower was evacuated and the fire extinguished in less than 40 minutes. There were no casualties.