Eiffel Tower
The Eiffel Tower (French: La Tour Eiffel, [tuʁ ɛfɛl]) is an iron lattice tower located on the Champ de Mars in Paris, named after the engineer Gustave Eiffel, whose company designed and built the tower. Erected in 1889 as the entrance arch to the1889 World's Fair, it has become both a global cultural icon of France and one of the most recognizable structures in the world. The tower is the tallest structure in Paris[10] and the most-visited paid monument in the world; 7.1 million people ascended it in 2011. The tower received its 250 millionth visitor in 2010.
The tower stands 324 metres (1,063 ft) tall, about the same height as an 81-story building. During its construction, the Eiffel Tower surpassed the Washington Monument to assume the title of the tallest man-made structure in the world, a title it held for 41 years, until the Chrysler Building in New York City was built in 1930. Because of the addition of the antenna atop the Eiffel Tower in 1957, it is now taller than the Chrysler Building by 17 feet (5.2 m). Not including broadcast antennas, it is the second-tallest structure in France, after the Millau Viaduct.
History
Origin
The design of the Eiffel Tower was originated by Maurice Koechlin and Émile Nouguier, two senior engineers who worked for the Compagnie des Etablissements Eiffel after discussion about a suitable centrepiece for the proposed 1889 Exposition Universelle, a World's Fairwhich would celebrate the centennial of the French Revolution. In May 1884, Koechlin, working at home, made an outline drawing of their scheme, described by him as "a greatpylon, consisting of four lattice girders standing apart at the base and coming together at the top, joined together by metal trusses at regular intervals".[11] Initially Eiffel himself showed little enthusiasm, but he did sanction further study of the project, and the two engineers then asked Stephen Sauvestre, the head of company's architectural department, to contribute to the design. Sauvestre added decorative arches to the base, a glass pavilion to the first level and other embellishments. This enhanced version gained Eiffel's support, and he bought the rights to the patent on the design which Koechlin, Nougier, and Sauvestre had taken out, and the design was exhibited at the Exhibition of Decorative Arts in the autumn of 1884 under the company name. On 30 March 1885 Eiffel presented a paper on the project to the Société des Ingiénieurs Civils; after discussing the technical problems and emphasising the practical uses of the tower, he finished his talk by saying that the tower would symbolise
"not only the art of the modern engineer, but also the century of Industry and Science in which we are living, and for which the way was prepared by the great scientific movement of the eighteenth century and by the Revolution of 1789, to which this monument will be built as an expression of France's gratitude."
The "Artists Protest"
The projected tower had been a subject of some controversy, attracting criticism both from those who did not believe that it was feasible and also from those who objected on artistic grounds. Their objections were an expression of a longstanding debate about the relationship between architecture and engineering. This came to a head as work began at the Champ de Mars: A "Committee of Three Hundred" (one member for each metre of the tower's height) was formed, led by the prominent architect Charles Garnier and including some of the most important figures of the French arts establishment, including Adolphe Bouguereau, Guy de Maupassant, Charles Gounod and Jules Massenet: a petition was sent toCharles Alphand, the Minister of Works and Commissioner for the Exposition, and was published by Le Temps.
Construction
Work on the foundations started in January 1887. Those for the east and south legs were straightforward, each leg resting on four 2 m (6.6 ft) concrete slabs, one for each of the principal girders of each leg but the other two, being closer to the river Seine, were more complicated: each slab needed two piles installed by using compressed-air caissons 15 m (49 ft) long and 6 m (20 ft) in diameter driven to a depth of 22 m (72 ft)
to support the concrete slabs, which were 6 m (20 ft) thick. Each of these slabs supported a block built oflimestone each with an inclined top to bear a supporting shoe for the ironwork. Each shoe was anchored into the stonework by a pair of bolts 10 cm (4 in) in diameter and 7.5 m (25 ft) long. The foundations were complete by 30 June and the erection of the ironwork began. The very visible work on-site was complemented by the enormous amount of exacting preparatory work that was entailed: the drawing office produced 1,700 general drawings and 3,629 detailed drawings of the 18,038 different parts needed.
The task of drawing the components was complicated by the complex angles involved in the design and the degree of precision required: the position of rivet holes was specified to within 0.1 mm (0.04 in) and angles worked out to one second of arc. The finished components, some already riveted together into sub-assemblies, arrived on horse-drawn carts from the factory in the nearby Parisian suburb of Levallois-Perret and were first bolted together, the bolts being replaced by rivets as construction progressed. No drilling or shaping was done on site: if any part did not fit it was sent back to the factory for alteration. In all there were 18,038 pieces joined by two and a half million rivets.
Inauguration and the 1889 Exposition
The main structural work was completed at the end of March 1889 and on the 31st Eiffel celebrated this by leading a group of government officials, accompanied by representatives of the press, to the top of the tower. Since the lifts were not yet in operation, the ascent was made by foot, and took over an hour, Eiffel frequently stopping to make explanations of various features. Most of the party chose to stop at the lower levels, but a few, including Nouguier, Compagnon, the President of the City Council and reporters from Le Figaro and Le Monde Illustré completed the climb. At 2.35 Eiffel hoisted a large tricolore, to the accompaniment of a 25-gun salute fired from the lower level. There was still work to be done, particularly on the lifts and the fitting out of the facilities for visitors, and the tower was not opened to the public until nine days after the opening of the Exposition on 6 May, and even then the lifts had not been completed.
The tower was an immediate success with the public, and lengthy queues formed to make the ascent. Tickets cost 2 francs for the first level, 3 for the second, and 5 for the top, with half-price admission on Sundays, and by the end of the exhibition there had been nearly two million visitors.
Eiffel had a permit for the tower to stand for 20 years; it was to be dismantled in 1909, when its ownership would revert to the City of Paris. The City had planned to tear it down (part of the original contest rules for designing a tower was that it could be easily demolished) but as the tower proved valuable for communication purposes, it was allowed to remain after the expiration of the permit. In the opening weeks of World War I, powerful radio transmitters were fitted to the tower in order to jam German communications. This seriously hindered their advance on Paris, and contributed to the Allied victory at the First Battle of the Marne.
The 1889 Exposition Universelle for which the Eiffel Tower was built. For over forty years after its construction, the Eiffel Tower was the tallest man-made structure in the world.
Subsequent events
10 September 1889
To M Eiffel the Engineer the brave builder of so gigantic and original specimen of modern Engineering from one who has the greatest respect and admiration for all Engineers including the Great Engineer the Bon Dieu, Thomas Edison.
