Paris and cosmic rays

I just stumbled across this Scientific American blog post, which describes early 20th century efforts to understand the source of a newly recognized and mysterious radiation: did it come from radioactive elements in the earth, or from the sky? The Eiffel Tower was crucial to the story of how one scientist obtained the first significant evidence that some of this radiation (what we call cosmic rays today) originates well beyond our atmosphere in cosmic events such as supernovas. I had no idea that Gustave Eiffel argued that the tower had potential as a scientific research station, but he was correct. (One of his suggestions was that an observatory be placed at the top of the tower. I love this idea, but the lights of Paris—not to mention the lights on the tower itself—would make observing most objects very difficult. I wonder if there are any efforts to make the City of Light more dark-sky friendly?)