<P> For the 1900 Exposition Universelle, the lifts in the east and west legs were replaced by lifts running as far as the second level constructed by the French firm Fives - Lille . These had a compensating mechanism to keep the floor level as the angle of ascent changed at the first level, and were driven by a similar hydraulic mechanism to the Otis lifts, although this was situated at the base of the tower . Hydraulic pressure was provided by pressurised accumulators located near this mechanism . At the same time the lift in the north pillar was removed and replaced by a staircase to the first level . The layout of both first and second levels was modified, with the space available for visitors on the second level . The original lift in the south pillar was removed 13 years later . </P> <P> On 19 October 1901, Alberto Santos - Dumont, flying his No. 6 airship, won a 100,000 - franc prize offered by Henri Deutsch de la Meurthe for the first person to make a flight from St. Cloud to the Eiffel Tower and back in less than half an hour . </P> <P> Many innovations took place at the Eiffel Tower in the early 20th century . In 1910, Father Theodor Wulf measured radiant energy at the top and bottom of the tower . He found more at the top than expected, incidentally discovering what are known today as cosmic rays . Just two years later, on 4 February 1912, Austrian tailor Franz Reichelt died after jumping from the first level of the tower (a height of 57 metres) to demonstrate his parachute design . In 1914, at the outbreak of World War I, a radio transmitter located in the tower jammed German radio communications, seriously hindering their advance on Paris and contributing to the Allied victory at the First Battle of the Marne . From 1925 to 1934, illuminated signs for Citroën adorned three of the tower's sides, making it the tallest advertising space in the world at the time . In April 1935, the tower was used to make experimental low - resolution television transmissions, using a shortwave transmitter of 200 watts power . On 17 November, an improved 180 - line transmitter was installed . </P> <P> On two separate but related occasions in 1925, the con artist Victor Lustig "sold" the tower for scrap metal . A year later, in February 1926, pilot Leon Collet was killed trying to fly under the tower . His aircraft became entangled in an aerial belonging to a wireless station . A bust of Gustave Eiffel by Antoine Bourdelle was unveiled at the base of the north leg on 2 May 1929 . In 1930, the tower lost the title of the world's tallest structure when the Chrysler Building in New York City was completed . In 1938, the decorative arcade around the first level was removed . </P>

How high up is the first floor of the eiffel tower