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 Talented men
 
 
 
       The generosity of Bischoffsheim who  liked to say that he was just  "the cashier"  and that he  alone"took care of the means to succeed at the result", was rewarded.   Talented men  marked the first decades.
 
       First of all,  Henri  Perrotin was the  first director of this magnificent realization. By his undeniable qualities of managing, and his personal works he contributed very much to the fame of the Establishment. He knew how to choose a skillful staff, and to attract high-level scholars.  
 
        Perrotin made notable studies on planets: his observations of the March surface contributed to make  progress to the cartography of  the planet; his researches on   Venus rotation attracted attention, even though  the data were badly  missing at that time to let him to do a correct measure of its rotation speed ; and he perceived new details in the Saturn rings. As concerns  the small planets,  he made the Vesta's theory.

    Perrotin  also studied nebulae double stars that were so closed to one another  that they were unobservable any where else  in Europe,  meteorology and  Earth magnetism.

 
       He realized with Alfred Cornu,  famous experiments of the measure of the speed of light between  the Mont Gros and La Gaude (12km) and carried on them with his assistants  Prim and Simonin, between the Mont Gros and the Mont Vinaigre (Estérel) (46km), improving his determination, with a  precision  that will  be superseded only twenty years later. Finally,  he laid the foundations of the Annals of Nice Observatory.
 
                                     
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      Louis Thollon, who had begun his observations at the Mont Gros even before the Observatory was built, dedicated the major part of his activity to the Sun, and measured its rotation, comparing the Doppler effect of the solar lines  with fixed telluric lines. He studied the movements in the sun protuberances, their helical complexity, and he brought to light speeds of the order of 500km /sec-1.
 
       Of his systematic study of the solar spectrum, Thollon made a  large  atlas published after his death, in 1890.  The spectra  extended over 3448 lines,  the double of  Angström's classical atlas , and  a third part of these lines were clearly identified by Thollon as being of telluric origin. The whole was of a remarkable precision for its time and it was the most important document on the solar spectrum  ever realized with the spectroscope. A better result will be obtained only by  spectrography.
 
      Alexandre  Schaumasse and  Michel   Giacobini discovered a large number of   comets. From 1896 till 1907, Giacobini  discovered 12 comets among which two are periodical: comets  Tuttle-Giacobini and  Giacobini-Zinner.   
 
     Auguste Charlois was called " the ferret of small planets ", because he discovered hundred of asteroids. His career was brutally interrupted in 46 years old, when  he was murdered by his brother-in-law. This event was in the local news and threw  the scientific world into  consternation.  
 
    Charles  Nordmann was one of the precursors of  radio astronomy. He came at the Observatory when he was very young and he there prepared a thesis and  published original articles on an experience  which he undertook,  in 1901, on the slopes of the Mont Blanc (French Alps) in order  to  detect the Hertzian   radiation of the Sun . He was not able to prove it, because he worked at a time of minimum activity of the Sun and at too long  wavelengths taht are essentially  blocked  by the ionosphere.  He carried on his career at the Paris Observatory, by making remarked photometric studies  of the  variable stars, and theoretical researches on the intrinsic state of the Sun.
 
      In 1892, the coudé equatorial, the principle of which was due to Loewy was put in service and indicated the beginning of the photographic observations  for  comets and planets researches.
 
      The next year, at the request of Perrotin,  Bischoffsheim settled an annex station of observation  for the study  of big planets and   particularly the rotation of Venus, at the top of one of the summits of the Maritime Alps, the Mont Mounier (2740m), above Valberg, in the district of  Puget-Théniers where he just hapenned to  be elected as  a member of parliament. Meteorological observations   were also made there, but the station was abandoned in 1910.
 

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