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
Eiffel Tower wind forces, and knew that if they were going to build the tallest structure in the world, they had to be sure it could withstand them. In an interview with the newspaper "Le Temps" published on 14 February 1887, Eiffel said: He used graphical methods to determine the strength of the tower and empirical evidence to account for the effects of wind, rather than a mathematical formula. Close examination of the tower reveals a basically exponential shape. All parts of the tower were over-designed to ensure maximum resistance to wind forces. The top half was even assumed to have no