PARIS.- The Eiffel Tower, the most visited paid monument in the world, symbol of France and Europe, had its 120th birthday this week. To celebrate de anniversary of the monument designed by Gustave Eiffel, the government of the city of Paris has decided to apply new painting on the monument.

When the tower was completed in 1889 it was the world's tallest tower — a title it retained until 1930 when New York City's Chrysler Building (319 m — 1,047 ft tall) was completed. The tower is now the fifth-tallest structure in France and the tallest structure in Paris, with the second-tallest being the Tour Montparnasse (210 m — 689 ft), although that will soon be surpassed by Tour AXA.

The structure was built between 1887 and 1889 as the entrance arch for the Exposition Universelle, a World's Fair marking the centennial celebration of the French Revolution. Eiffel originally planned to build the tower in Barcelona, for the Universal Exposition of 1888, but those responsible at the Barcelona city hall thought it was a strange and expensive construction, which did not fit into the design of the city. After the refusal of the Consistory of Barcelona, Eiffel submitted his draft to those responsible for the Universal Exhibition in Paris, where he would build his tower a year later, in 1889. The tower was inaugurated on 31 March 1889, and opened on 6 May. Three hundred workers joined together 18,038 pieces of puddled iron (a very pure form of structural iron), using two and a half million rivets, in a structural design by Maurice Koechlin. The risk of accident was great, for unlike modern skyscrapers the tower is an open frame without any intermediate floors except the two platforms. However, because Eiffel took safety precautions, including the use of movable stagings, guard-rails and screens, only one man died.

Gustave Eiffel
An engineer by training, Eiffel founded and developed a company specializing in metal structural work, whose crowning achievement was the Eiffel Tower. He devoted the last thirty years of his life to his experimental research.

Born in Dijon in 1832, he graduated from the Ecole Centrale des Arts et Manufactures in 1855, the same year that Paris hosted the first world's Fair. He spent several years in the South West of France, where he supervized work on the great railway bridge in Bordeaux, and afterwards he set up in his own right in 1864 as a "constructor", that is, as a business specializing in metal structural work. His outstanding career as a constructor was marked by work on the Porto viaduct over the river Douro in 1876, the Garabit viaduct in 1884, Pest railway station in Hungary, the dome of the Nice observatory, and the ingenious structure of the Statue of Liberty. It culminated in 1889 with the Eiffel Tower.

After the end of his career in business, marred by the failure of the Panama Canal, Eiffel began an active life of scientific experimental research in the fields of meteorology, radiotelegraphy and aerodynamics. He died on December 27 1923.

Eiffel built hundreds of metal structures of all kinds all around the world.
Eiffel built hundreds of metal structures of all kinds, all around the world. Bridges, and in particular railway bridges, were his favourite field of work, but he also won renown for his metal structural work and industrial installations. His career was marked by a large number of fine buildings, among which two of the most outstanding are the twin edifices of the Porto viaduct and the Garabit viaduct in the Cantal region of France. Equally outstanding are certain other structures in which the pure inventiveness of Eiffel's company was allowed free rein, such as the "portable" bridges sold around the world in "kits", the ingenious structure of the Statue of Liberty in New York, and of course the Eiffel Tower itself.

In 1887 Eiffel agreed to build the locks of the Panama canal, an immense undertaking badly managed by Ferdinand De Lesseps, which ended in the biggest financial scandal of the century.

This was the biggest contract in his entire career in business, and also the one with the greatest risk. Given the risk he faced, he was granted major financial advantages and solid guarantees, which allowed him to collect his profit as soon as the work was begun. Despite the care which Eiffel took in the project, the liquidation of the canal construction company, Compagnie du Canal, on February 4 1889, led to his own indictment for fraud alongside De Lesseps and his son, and to a sentence of two years in prison and a fine of 2000 francs, even though nothing could really be blamed on him personally. With his honour and dignity severely compromised, he withdrew from business. The ruling was later to be annulled by the highest appeal court, the Cour de Cassation, liberating him of all obligations concerning the accusations, which put an end to any further court action against him.

In retirement following the Panama scandal, Eiffel devoted the final thirty years of his life to a fruitful career as a scientist.

The Tower Conception and Design
The plan to build a tower 300 metres high was conceived as part of preparations for the World's Fair of 1889.

Emile Nouguier and Maurice Koechlin, the two chief engineers in Eiffel's company, had the idea for a very tall tower in June 1884. It was to be designed like a large pylon with four columns of lattice work girders, separated at the base and coming together at the top, and joined to each other by more metal girders at regular intervals. The company had by this time mastered perfectly the principle of building bridge supports. The tower project was a bold extension of this principle up to a height of 300 metres - equivalent to the symbolic figure of 1000 feet. On September 18 1884 Eiffel registered a patent "for a new configuration allowing the construction of metal supports and pylons capable of exceeding a height of 300 metres".

In order to make the project more acceptable to public opinion, Nouguier and Koechlin commissioned the architect Stephen Sauvestre to work on the project's appearance.

Sauvestre proposed stonework pedestals to dress the legs, monumental arches to link the columns and the first level, large glass-walled halls on each level, a bulb-shaped design for the top and various other ornamental features to decorate the whole of the structure. In the end the project was simplified, but certain elements such as the large arches at the base were retained, which in part give it its very characteristic appearance.

The curvature of the uprights is mathematically determined to offer the most efficient wind resistance possible. As Eiffel himself explains: "All the cutting force of the wind passes into the interior of the leading edge uprights. Lines drawn tangential to each upright with the point of each tangent at the same height, will always intersect at a second point, which is exactly the point through which passes the flow resultant from the action of the wind on that part of the tower support situated above the two points in question. Before coming together at the high pinnacle, the uprights appear to burst out of the ground, and in a way to be shaped by the action of the wind".

Painting the Eiffel Tower
Being made of iron, the Tower has been protected from oxidation by many layers of paint, which ensure that it will last for ever.

In 1900 in his book " The 300-Meter Tower ", Gustave Eiffel wrote, "We will most likely never realize the full importance of painting the Tower, that it is the essential element in the conservation of metal works and the more meticulous the paint job, the longer the Tower shall endure."

The Tower has been re-painted 18 times since its initial construction, an average of once every seven years. It has changed colour several times, passing from red-brown to yellow-ochre, then to chestnut brown and finally to the bronze of today, slightly shaded off towards the top to ensure that the colour is perceived to be the same all the way up as it stands against the Paris sky. Sixty tons of paint are necessary to cover the Tower's surface, as well as 50 kilometers of security cords, 5 acres of protection netting, 1500 brushes, 5000 sanding disks, 1500 sets of work clothes…and more than a year for a team of 25 painters to paint the Tower from top to bottom.

The 19th repainting of the Eiffel Tower got underway in March 2009.