Battle of Iwo Jima Date 19 February – 26 March 1945 (1 month and 1 week) Location Iwo Jima, Volcano Islands, Japan Result American victory USAAF fighter aircraft able to escort B-29's on missions to Japan. Americans gain an emergency landing base for damaged aircraft returning from missions on Japan. Belligerents United States Japan Commanders and leaders U.S. Navy: Chester W. Nimitz Raymond A. Spruance Marc A. Mitscher William H. P. Blandy U.S. Marine Corps: Holland M. Smith Harry Schmidt Graves B. Erskine Clifton B. Cates Keller E. Rockey Tadamichi Kuribayashi † Takeichi Nishi † Sadasue Senda † Rinosuke Ichimaru † Units involved American: Ground units: V Amphibious Corps 3rd Marine Division 4th Marine Division 5th Marine Division 147th Infantry Regiment (separate) Aerial units: Seventh Air Force Naval units: 5th Fleet Joint Expeditionary Force (TF 51) Amphibious Support Force (TF 52) Attack Force (TF 53) Expeditionary Troops (TF 56) Fast Carrier Force (T...
Eiffel Tower
Type
Observation tower
Broadcasting tower
Location
7th arrondissement, Paris, France
Coordinates
48°51′29.6″N 2°17′40.2″E
Construction started
28 January 1887; 134 years ago
Completed
15 March 1889; 132 years ago
Opening
31 March 1889; 132 years ago
Owner
City of Paris, France
Management
Société d'Exploitation de la Tour Eiffel (SETE)
Height
Architectural
300 m (984 ft)
Tip
324 m (1,063 ft)
Top floor
276 m (906 ft)
Technical details
Floor count
3
Lifts/elevators
8
Design and construction
Architect
Stephen Sauvestre
Structural engineer
Maurice Koechlin
Émile Nouguier
Main contractor
Compagnie des Etablissements Eiffel
Eiffel Tower, French Tour Eiffel, Parisian landmark that is also a technological masterpiece in building-construction history. When the French government was organizing the International Exposition of 1889 to celebrate the centenary of the French Revolution, a competition was held for designs for a suitable monument. More than 100 plans were submitted, and the Centennial Committee accepted that of the noted bridge engineer Gustave Eiffel. Eiffel’s concept of a 300-metre (984-foot) tower built almost entirely of open-lattice wrought iron aroused amazement, skepticism, and no little opposition on aesthetic grounds. When completed, the tower served as the entrance gateway to the exposition.
Nothing remotely like the Eiffel Tower had ever been built; it was twice as high as the dome of St. Peter’s in Rome or the Great Pyramid of Giza. In contrast to such older monuments, the tower was erected in only about two years (1887–89), with a small labour force, at slight cost. Making use of his advanced knowledge of the behaviour of metal arch and metal truss forms under loading, Eiffel designed a light, airy, but strong structure that presaged a revolution in civil engineering and architectural design. And, after it opened to the public on May 15, 1889, it ultimately vindicated itself aesthetically.
The Eiffel Tower stands on four lattice-girder piers that taper inward and join to form a single large vertical tower. As they curve inward, the piers are connected to each other by networks of girders at two levels that afford viewing platforms for tourists. By contrast, the four semicircular arches at the tower’s base are purely aesthetic elements that serve no structural function. Because of their unique shape, which was dictated partly by engineering considerations but also partly by Eiffel’s artistic sense, the piers required elevators to ascend on a curve; the glass-cage machines designed by the Otis Elevator Company of the United States became one of the principal features of the building, helping establish it as one of the world’s premier tourist attractions.
The tower itself is 300 metres (984 feet) high. It rests on a base that is 5 metres (17 feet) high, and a television antenna atop the tower gives it a total elevation of 324 metres (1,063 feet). The Eiffel Tower was the tallest structure in the world until the topping off of the Chrysler Building in New York City in 1929.
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