sentences:  Between September 1903 and October 1904 a number of attempts at flight were made, and he also constructed a tall latticework tower supporting a long counterbalanced revolving arm from which the aircraft was suspended.Ferber wrote that trials of this machine "were completely useless, but drew public attention to aviation"
  
  In April 1904 Ferber assisted Ernest Archdeacon with the trials of his Wright-derived glider at Berck-sur-Mer.Shortly after this Charles Renard, commander of the French Army balloon school at Chalais-Meudon, invited Ferber to join this establishment, and he took up this new post in early May 1904.