Eiffel Tower In 1909, a permanent underground radio centre was built near the south pillar, which still exists today. On 20 November 1913, the Paris Observatory, using the Eiffel Tower as an aerial, exchanged wireless signals with the United States Naval Observatory, which used an aerial in Arlington, Virginia. The object of the transmissions was to measure the difference in longitude between Paris and Washington, D.C. Today, radio and digital television signals are transmitted from the Eiffel Tower. A television antenna was first installed on the tower in 1957, increasing its height by 18.7 m (61.4 ft). Work carried out in 2000
Gustave Eiffel the Cantal département. Like the Douro bridge, the project involved a lengthy viaduct crossing the river valley as well as the river itself, and Eiffel was given the job without any process of competitive tendering due to his success with the bridge over the Douro. To assist him in the work he took on several people who were to play important roles in the design and construction of the Eiffel Tower, including Maurice Koechlin, a young graduate of the Zurich Polytechnikum, who was engaged to undertake calculations and make drawings, and Émile Nouguier, who had previously worked for Eiffel on