Eiffel Tower 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 should be easy to dismantle) but as the tower proved to be valuable for communication purposes, it was allowed to remain after the expiry of the permit. Eiffel made use of his apartment at the top of the tower to carry out meteorological observations, and also used the tower to perform experiments on the action of air resistance on falling bodies. For the
Eiffel Tower box surrounding the tower (324 m x 125 m x 125 m) would contain tons of air, weighing almost as much as the iron itself. Depending on the ambient temperature, the top of the tower may shift away from the sun by up to due to thermal expansion of the metal on the side facing the sun. When it was built, many were shocked by the tower's daring form. Eiffel was accused of trying to create something artistic with no regard to the principles of engineering. However, Eiffel and his team – experienced bridge builders – understood the importance of